optical design projection optics augmented reality & head mounted display
TRANSCRIPT
3M Electronics Materials Solutions Division, St. Paul
Presented by Dr. Zhisheng Yun
09-01-2016
Efficient 3M PBS Enhancing Miniature Projection Optics
2. All Rights Reserved.2 September 2016© 3M 3M Confidential.
Outline
• 3M Giant Birefringence Multilayer Optical Film (MOF)
• 3M Polarization Beam Splitter (PBS)
• 3M Miniature Optical Systems of MM100, MM200, MM300 and
Tiny Projection Light Engine
• Optical Performance of Light Engine Summary
• Acknowledgment
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Ideal Polarization Beam Splitter Multilayer Films
For high S-pol reflectivity: nx1>>nx2
For high transmission of P-pol and low
color: ny1 = ny2 = nz1 = nz2
Stretch Direction
z
nx1
nx2
xy
nz1
nz2
Incident light S-pol
P-pol
Reference: Michael F. Weber, Carl A. Stover, Larry R. Gilbert, Timothy J. Nevitt, Andrew J. Ouderkirket., Science 287 (5462), 2451-2456, (2000)
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Birefringent Multilayer PBS Films
• Coextrude two thermally processable polymers
— One positively birefringent, the other, isotropic
• Create a variety of layer pair thicknesses to cover a range of
wavelengths
• Stretch to increase the refractive index of the birefringent layer
— “Ideal” orientation: the draw ratio (DR) of the non-stretch directions (Y and
Z) is equal to the inverse square root of the draw ratio in the stretch direction
(X)
DRxDRzDRy /1
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Schematic of Stretching Multilayer Optical Films
Cast Web Pre-HeatStretch Output
Stretched Film
Edge trim
Trim
Tenter Chain
Set
VinVout= Vin
OVEN
x
y
Four major MOF manufacture steps:o Cast Webo Preheato Stretcho Setting
Reference: Martin E. Denker, Andrew T. Ruff, Kris Derks Invited Paper: “Advanced Polarizer Film for Improved Performance of Liquid Crystal Displays”, SID Symposium Digest of Technical Papers, Vol 37, Issue 1, p. 1528-1530, 2006.
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3M PBS vs WG PBS
Light path within PBS
WG PBS 3M PBS
3M PBS vs Wire Grid PBS
Display with Linear Polarized Light
MirrorBonded QWP
WG 3M
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3M PBS vs Wire Grid and MacNeille PBS
• Measurement data of 3M PBS vs Wire Grid and MacNeille PBS
• On-axis measurement results:
* MacNeille and wire grid PBS were from Throlabs and the part numbers are PBS251 and WPBS254.
Rs Ts Tp Rp Efficiency (Rs*Tp)
3M PBS 96.9% 0.09% 98.3% 0.10% 95.2%
McNeille* 93.1% 0.07% 96.6% 0.67% 89.9%
WireGride* 80.5% 0.02% 76.4% 3.99% 61.5%
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Optical System of Light Engine MM100
Technologies developed in the MM100
optical system
• Low birefringence and curved PBS
• High efficiency with light recycle using with
3M reflective polarizer
• Unique Fresnel lens with Kohler illumination
configuration with system
Gen_1_Opcon_Solitaire1.3.ZMXConfiguration 1 of 1
Layout
8/22/2016Total Axial Length: 36.50326 mm
0 3 6 9 12 15 18 21 24 27 30
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Spatial Frequency in cycles per mm
TS 0.00 mmTS -50.00 mm
TS -100.00 mmTS -175.00 mmTS -200.00 mm
TS -250.00 mm
Gen_1_Opcon_Solitaire1.3.ZMXConfiguration 1 of 1
Modulus of the OTF
Polychromatic Diffraction MTF
8/22/2016Data for 0.4600 to 0.6300 µm.Surface: Image
Reference: Ardashnikov, B., Duncan, J., Glinski,A., Grace, J., Pol, T., Phillips, B., Ridgeway, C., Rutherford, T., Shiba, E., VanOverloop, R., “A Mobile Projection Engine With A Multi-layer Reflective Polarizer Based PBS”, Proc. SID , 70.5L, 2008
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Optical System of Light Engine MM200
Efficient Optical System Design
• Solid rod and ball lens for light collection and color mixing
• Aspheric illumination optics
High Efficiency Polarizing Beam Splitter (PBS)
• 3M Multilayer Optical Film Component
• High contrast
• High efficiency
• Low f/#
• Lensed PBS surface
High brightness LED Polarization recycling scheme
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Optical System of Light Engine MM200
Projection Lens
PBS
LCOS ImagerIlluminator
Efficient Optical System Design• Light engine opto-mechanical system
• Cross section view of the illuminator collection and color mixing
Reference: Phillips, B., Grace, J., Yun, Z., Willett, S., Snively, D., Pol, T., Ardashnikov, B., O’Shea, G., “A High Efficiency Mobile Projection Engine Utilizing Color Sequential Illumination”, Proc. SID, 14.5, 2009
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Optical System Of Light Engine MM300MM300 Technologies
• Polarization converter
• Lens array and relay optics
• Efficient 3M PBS technology
Blue
Red
Green
Polarization
converter
Lensarray
Relay lens
PBSField
lensProjection
lens group
0 5.6 11.2 16.8 22.4 28 33.6 39.2 44.8 50.4 56
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Spatial Frequency in cycles per mm
TS 0.0000 mmTS 1.7489 mm
TS 3.2005 mmTS 4.1448 mmTS 5.2744 mm
TS 6.1072 mmTS 7.1100 mm
100Offset_0.42_PJlens_F1.62_VH001_Cyc449_Released.zmxConfiguration 1 of 3
Modulus of the OTF
Polychromatic Diffraction MTF
MM300 Projection Lens Cycle4498/22/2016Data for 0.4600 to 0.6150 µm.Surface: Image
100Offset_0.42_PJlens_F1.62_VH001_Cyc449_Released.zmxConfiguration 1 of 3
Layout
MM300 Projection Lens Cycle4498/22/2016Total Axial Length: 61.79562 mm
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Optical System of Tiny Projector
Technologies in the tiny projector
optical system:
• High efficiency MOF
• Sophisticated PBS
• LED light collection and relay lens
• Light Re-cycle film used
• The system designed for color filter LCOS
imager with a white LED.
• The system also works for color sequential
LCOS imager with an additional color
mixing short rod.
Reference: Yun, Z., Ouderkirk, J. A., Tan, L. K., Tio, T. A., “Compact Illuminator”, US patent
application 2013/0063671
Projection
lens group
Imager
Field lens
LED collection
lens
Reflective
Polarizer
LED light
source
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Comparison of 3M Pico Projection Optical Systems
Parameter MM100 MM200 MM300
Tiny Projector
(target specs)
Brightness at given
LED power (lm/W) 5.6lm/1W
8.0lm/1W
15.0lm/2.5W
8.5lm/W
68lm/8W
9.0lm/1W
30lm/4W
ANSI contrast 80 to 1 97 to 1 120 to 1 120 to 1
Resolution (Pixels) 640x480x3 640x480 1024x600 800x600
Modle Size (mm) 13.7x34.0x12.5 37.9x36x10.5 62.5x65x20.5 10.0x25.0x30.0
Weight (g) 21 14 70.5 9
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Acknowledgements
• 3M Electronics Material Solutions Division, 3M Display Materials
Solutions Division and Electronics and Energy Laboratory
• Coauthors and contributors
• SPIE Organization Committee