rahul krishnan seminar adaopt
TRANSCRIPT
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 126
An Introduction to AdaptiveOptics
BY
RAHUL KRISHNAN
S7 EEE
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 226
Why do we need adaptive optics
To Correct for Irregularities in theTransmission Media ndash Atmospheric (Astronomical)
Scintillation or Twinkling (Eddies ~ radicλL)
Beam Wander or Quiver (Eddies gt Beam Size)
Spreading (Eddies lt Beam Size)
ndash Atmospheric (LASER Transmission) Thermal Blooming
ndash Ocular (Retinal Imaging) Defects in the Lens and Cornea
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 426
Astronomical AO ExampleNeptune
415
Without adaptive optics With adaptive optics
2
3
a r c
s e c
Credit Keck Observatory LLNL UCB
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 526
Essentials of anAO system
Wavefront sensor
Computer
Phase modulator
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 626
How Turbulence Effects Light
Spherical wavesemitted by thesource (star) areessentially planewaves when theyarrive at the Earthrsquosatmosphere Thewaves are thenrandomly distorted
by turbulence in the
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 726
How does it work
Two Basic Functions
ndash Wavefront sensing
Shack-Hartmann wavefront sensor
Shearing interferometer
ndash Wavefront correction
Tip-tilt optical element
Deformable optical element
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 826
Wavefront Sensing
Shack-HartmannSensor
ndash Has become the
standard type of sensor ndash Uses an array of
spherical ldquolenseletsrdquo
ndash Focuses wavefronts
onto a CCD array ndash (b) is a plane wave
ndash (c) is a distorted wave
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 926
Wavefront Sensing
ShearingInterferometer
ndash Distorted wavefronts
result in phase shiftedoutput signals betweenthe detector arrays
ndash Two interferometers are
required for correctionin the x-y plane
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 226
Why do we need adaptive optics
To Correct for Irregularities in theTransmission Media ndash Atmospheric (Astronomical)
Scintillation or Twinkling (Eddies ~ radicλL)
Beam Wander or Quiver (Eddies gt Beam Size)
Spreading (Eddies lt Beam Size)
ndash Atmospheric (LASER Transmission) Thermal Blooming
ndash Ocular (Retinal Imaging) Defects in the Lens and Cornea
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 426
Astronomical AO ExampleNeptune
415
Without adaptive optics With adaptive optics
2
3
a r c
s e c
Credit Keck Observatory LLNL UCB
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 526
Essentials of anAO system
Wavefront sensor
Computer
Phase modulator
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 626
How Turbulence Effects Light
Spherical wavesemitted by thesource (star) areessentially planewaves when theyarrive at the Earthrsquosatmosphere Thewaves are thenrandomly distorted
by turbulence in the
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 726
How does it work
Two Basic Functions
ndash Wavefront sensing
Shack-Hartmann wavefront sensor
Shearing interferometer
ndash Wavefront correction
Tip-tilt optical element
Deformable optical element
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 826
Wavefront Sensing
Shack-HartmannSensor
ndash Has become the
standard type of sensor ndash Uses an array of
spherical ldquolenseletsrdquo
ndash Focuses wavefronts
onto a CCD array ndash (b) is a plane wave
ndash (c) is a distorted wave
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 926
Wavefront Sensing
ShearingInterferometer
ndash Distorted wavefronts
result in phase shiftedoutput signals betweenthe detector arrays
ndash Two interferometers are
required for correctionin the x-y plane
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 426
Astronomical AO ExampleNeptune
415
Without adaptive optics With adaptive optics
2
3
a r c
s e c
Credit Keck Observatory LLNL UCB
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 526
Essentials of anAO system
Wavefront sensor
Computer
Phase modulator
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 626
How Turbulence Effects Light
Spherical wavesemitted by thesource (star) areessentially planewaves when theyarrive at the Earthrsquosatmosphere Thewaves are thenrandomly distorted
by turbulence in the
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 726
How does it work
Two Basic Functions
ndash Wavefront sensing
Shack-Hartmann wavefront sensor
Shearing interferometer
ndash Wavefront correction
Tip-tilt optical element
Deformable optical element
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 826
Wavefront Sensing
Shack-HartmannSensor
ndash Has become the
standard type of sensor ndash Uses an array of
spherical ldquolenseletsrdquo
ndash Focuses wavefronts
onto a CCD array ndash (b) is a plane wave
ndash (c) is a distorted wave
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 926
Wavefront Sensing
ShearingInterferometer
ndash Distorted wavefronts
result in phase shiftedoutput signals betweenthe detector arrays
ndash Two interferometers are
required for correctionin the x-y plane
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 426
Astronomical AO ExampleNeptune
415
Without adaptive optics With adaptive optics
2
3
a r c
s e c
Credit Keck Observatory LLNL UCB
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 526
Essentials of anAO system
Wavefront sensor
Computer
Phase modulator
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 626
How Turbulence Effects Light
Spherical wavesemitted by thesource (star) areessentially planewaves when theyarrive at the Earthrsquosatmosphere Thewaves are thenrandomly distorted
by turbulence in the
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 726
How does it work
Two Basic Functions
ndash Wavefront sensing
Shack-Hartmann wavefront sensor
Shearing interferometer
ndash Wavefront correction
Tip-tilt optical element
Deformable optical element
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 826
Wavefront Sensing
Shack-HartmannSensor
ndash Has become the
standard type of sensor ndash Uses an array of
spherical ldquolenseletsrdquo
ndash Focuses wavefronts
onto a CCD array ndash (b) is a plane wave
ndash (c) is a distorted wave
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 926
Wavefront Sensing
ShearingInterferometer
ndash Distorted wavefronts
result in phase shiftedoutput signals betweenthe detector arrays
ndash Two interferometers are
required for correctionin the x-y plane
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 526
Essentials of anAO system
Wavefront sensor
Computer
Phase modulator
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 626
How Turbulence Effects Light
Spherical wavesemitted by thesource (star) areessentially planewaves when theyarrive at the Earthrsquosatmosphere Thewaves are thenrandomly distorted
by turbulence in the
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 726
How does it work
Two Basic Functions
ndash Wavefront sensing
Shack-Hartmann wavefront sensor
Shearing interferometer
ndash Wavefront correction
Tip-tilt optical element
Deformable optical element
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 826
Wavefront Sensing
Shack-HartmannSensor
ndash Has become the
standard type of sensor ndash Uses an array of
spherical ldquolenseletsrdquo
ndash Focuses wavefronts
onto a CCD array ndash (b) is a plane wave
ndash (c) is a distorted wave
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 926
Wavefront Sensing
ShearingInterferometer
ndash Distorted wavefronts
result in phase shiftedoutput signals betweenthe detector arrays
ndash Two interferometers are
required for correctionin the x-y plane
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 626
How Turbulence Effects Light
Spherical wavesemitted by thesource (star) areessentially planewaves when theyarrive at the Earthrsquosatmosphere Thewaves are thenrandomly distorted
by turbulence in the
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 726
How does it work
Two Basic Functions
ndash Wavefront sensing
Shack-Hartmann wavefront sensor
Shearing interferometer
ndash Wavefront correction
Tip-tilt optical element
Deformable optical element
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 826
Wavefront Sensing
Shack-HartmannSensor
ndash Has become the
standard type of sensor ndash Uses an array of
spherical ldquolenseletsrdquo
ndash Focuses wavefronts
onto a CCD array ndash (b) is a plane wave
ndash (c) is a distorted wave
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 926
Wavefront Sensing
ShearingInterferometer
ndash Distorted wavefronts
result in phase shiftedoutput signals betweenthe detector arrays
ndash Two interferometers are
required for correctionin the x-y plane
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 726
How does it work
Two Basic Functions
ndash Wavefront sensing
Shack-Hartmann wavefront sensor
Shearing interferometer
ndash Wavefront correction
Tip-tilt optical element
Deformable optical element
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 826
Wavefront Sensing
Shack-HartmannSensor
ndash Has become the
standard type of sensor ndash Uses an array of
spherical ldquolenseletsrdquo
ndash Focuses wavefronts
onto a CCD array ndash (b) is a plane wave
ndash (c) is a distorted wave
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 926
Wavefront Sensing
ShearingInterferometer
ndash Distorted wavefronts
result in phase shiftedoutput signals betweenthe detector arrays
ndash Two interferometers are
required for correctionin the x-y plane
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 826
Wavefront Sensing
Shack-HartmannSensor
ndash Has become the
standard type of sensor ndash Uses an array of
spherical ldquolenseletsrdquo
ndash Focuses wavefronts
onto a CCD array ndash (b) is a plane wave
ndash (c) is a distorted wave
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 926
Wavefront Sensing
ShearingInterferometer
ndash Distorted wavefronts
result in phase shiftedoutput signals betweenthe detector arrays
ndash Two interferometers are
required for correctionin the x-y plane
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 926
Wavefront Sensing
ShearingInterferometer
ndash Distorted wavefronts
result in phase shiftedoutput signals betweenthe detector arrays
ndash Two interferometers are
required for correctionin the x-y plane
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1026
Wavefront Correction
High speed tip-tiltmirror reduces overallwavefront tilt
Deformable mirror(monolithic orsegmented) correctswavefront shape
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1126
Wavefront Correction Monolithic Deformable Mirror
ndash Reflective face cast on a solid piezoelectric backing (14um)
ndash Thin face supported by an array of electro-mechanical actuators (+- 30um) ndash Thin face supported by an array of piezoelectric actuators (50um)
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1226
Wavefront Correction
Segmented Mirrors
ndash Capable of largercorrections than
monolithic types ndash Requires frequent
calibration
ndash Diffraction due to gaps
between segments
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1326
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1426
Some Definitions
Apparent or VisualMagnitude ndash The relativebrightness of a star asseen by an observer on
Earth Guide Star ndash A sufficiently
bright star to use as areference for imagecompensation The
required magnitude variesas a function of the desiredobservation wavelength
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1526
Limitations of Image Compensation
Compensation in visible wavelengths (05um)requires a guide star of magnitude 10 or brighter
Compensation in infrared wavelengths (22um)
allows guide stars down to magnitude 14
Small isoplanatic region around the guide starlimits total observation area
ndash Visual ndash 1100000 of the sky ndash IR ndash 11000 of the sky
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1626
Guide Stars
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1726
Artificial Guide Stars
The area of sky coverage can beexpanded using artificial guide stars
Created using a LASER aligned withthe telescope optics
Rayleigh beacons take advantage ofRayleigh scattering in theatmosphere ndash Useful for telescopes with apertures lt 2m
ndash Creates a 1 to 2 arc second guide star 5 to
10km in altitude ndash 100W LASER
ndash LASER is pulsed so that backscatter can beeliminated by range gating
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1826
Artificial Guide Stars
Sodium Beaconsexploit a layer ofsodium vapor in the
upper atmosphere ndash 10W LASER at 589nm
ndash Excites sodium atoms90 to 92 km in altitude
Photo - The Sodium laser launching
from the side of the LickObservatory 120 ShaneTelescope This is a 10 minute timeexposure - note the star trails
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 1926
Artificial Guide Stars
Natural guide starrequired for tiltcorrection
Limiting magnitude forguide star is about 20
Result is nearly 100
sky coverage
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2026
IR Stellar imaging from Lick
Observatory
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2126
Upper Left Io imagetaken with Keckadaptive optics K-band 22 micron
Upper Right Io imagebased on visible lighttaken with Galileospacecraft orbiter
Lower Left Io imagetaken with Keckadaptive optics L-band35micron
Lower Right Io imagetaken without Keckadaptive optics
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2226
The Lick Observatory CIS
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2326
Non-Astronomical Applications
Most of the current AOtechnology wasdeveloped by DARPA
during the Cold War toimage and shoot downsatellites with LASERweapons
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2426
Retinal Imaging
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2526
References
Carroll Joseph Daniel C Gray Austin Roorda David R Williams ldquoRecent Advances inRetinal Imaging with Adaptive Opticsrdquo Optics and Photonics News Jan 2005 p 36-42
Chaisson Eric and Steve McMillan Astronomy Today 4th Edition Prentice Hall UpperSaddle River NJ 2002
Florence Ronald The Perfect Machine Harper Collins New York NY 1994
Hardy John W Adaptive Optics for Astronomical Telescopes Oxford University PressNew York NY 1998
Hardy John W ldquoAdaptive Opticsrdquo Scientific American June 1994 p 60-65
Hecht Eugene Optics 4th Edition Addison-Wesley Reading MA 2002
Tyson Robert K Principles of Adaptive Optics 2nd Edition Academic Press San DiegoCA 1998
AdaptiveOpticscom 2002 Adaptive Optics Associates Inc httpwwwaoainccom Center for Adaptive Optics 2005 University of California Santa Cruz
httpcfaoucolickorg
822019 Rahul Krishnan Seminar Adaopt
httpslidepdfcomreaderfullrahul-krishnan-seminar-adaopt 2626