polarization-maintaining fiber cables pmc- singlemode ... · pdf filefiber optic accessories...

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Kieler Str. 212, 22525 Hamburg, Germany • Tel: +49 40 85 39 97-0 • Fax: +49 40 85 39 97-79 • [email protected] • www.SuKHamburg.com

1501-2017 E

Polarization-Maintaining Fiber Cables PMC-… Singlemode Fiber Cables SMC-…Multimode Fiber Cables MMC-...

Accessories: Vacuum Feed-Through, Fiber Optic Beam Splitter, FC Adapter

• Wavelength 360 – 2000 nm• Mode field diameter 3 – 15 μm• Fiber with low attenuation for

wavelengths <460 nm• FC-APC or FC-PC fiber connector• Polarization direction aligned to

the connector index key

• Wavelength 360 – 2000 nm • Mode field diameter 2.4 – 15 μm• Fiber with low attenuation for wavelengths <460 nm• FC-APC or FC-PC fiber connector• Optionally: core-centering• Optionally: fiber connectors with end caps

Singlemode Fiber Cables SMC-...

Multimode Fiber Cables MMC-...

Polarization-Maintaining Singlemode Fiber Cables PMC-...

Lasers in Space

Optical Tweezers

Applications:

6 of 1000s X7

Flatbeam®-Laser 670

Fabry Perot Interferometry

Nanotube

A

MF

tomicorceicro-scopy

Laser for Adjustment and Alignment

• Option: fiber connectors with end caps

Dependence of the Mode Field Diameter on Wavelength and NAe2

Wavelength NAe2 MFD [μm]405 nm 0.06 / 0.09 4.2 / 2.9488 nm 0.06 / 0.08 4.8 / 3.7532 nm 0.06 / 0.075 5.9 / 4.5633 nm 0.07 5.5780 nm 0.08 6.41064 nm 0.08/ 0.06 8.0/111550 nm 0.08 12.3

• High OH-/ Low OH- for UV and VIS radia tion or VIS and NIR radiation, respectively

• FC-APC or FC-PC fiber connector (other connector types avai lable on request)

• Amagnetic titanium connec tors (FC-APC or FC-PC)

Fibers with End CapsIncreasing the mode field at the fiber end-face by a factor up to 10 and thus:

• reducing the power density by a factor up to 100• reducing the risk of fiber destruction by too high an optical power• reducing the tweezer effect

Fiber with End CapsReduced power density at fiber end-face (factor 100)

Standard Fiber

Fiber collimators 60FC-...Micro focus optic 5M-...

Anamorphic beam- shaping optics 5AN...

Faraday isolators 48FI-5...aping optics

N...

aday isolators FI-5...

Fiber Optic Accessories

inclined fiber coupling axis

nclined fiber couplingaxis

TILT

Vacuum feed-throughs V-KF-...

Fiber optic beam splitters FBS-...

Laser beam couplers 60 SMS-...feed-throughs V-KF-...

Application of multi-mode fibers MMC: generation of flatbeam profiles

Polarization Analyzer Series SK010PA-...USB Plug&Play for Wavelengths 350 - 1600nm

Polarization Analyzer Series SK010PA-...USB 2.0 Plug&Play for Wavelengths 375 – 1600nm

• Specific routines for PM fiber evaluation and alignment

• USB 2.0 powered device, Plug&Play

• Measurement of four Stokes parameters for display on a Poin caré sphere or as polarization ellipse

• Details see page 71.

Components for Photonic Crystal Fibers PCF-...

Optics for photonic crystal fibers:• FC-APC, FC-PC, F-SMA, SMA-905 High Power Connector (NKT

Photonics) (0°, 5° and 8°-polish)• Laser Beam Coupler and Fiber Collimators (also for

kineMATIX) available for all connector types (pages 9, 33, 44)• Fiber cables sold directly by NKT Photonics

Measurement System F

iber

cab

les

60FC-...Micro focus optic 5M-...

SM-FiberPM-FiberType Panda bber

PM-Fiber with

End Caps

PM-Fiberswith end capsreduced power density at fiber

end-face (factor 100)

Standard fiber

Fiber with End Caps

SM-Fiberswith end capsreduced power density at fiber


Standard fiber

Beam profile© NKT Photonics© NKT Pho© NKT P

P hotonicC rystalF iber

Sp

ec

tra

l ra

ng

e 1100

380

750

640

540

400

PM-Fiber

MultimodeFiber

Adjustment of Quarter-wave plates

USB 2.0USBUUUUUUU 2

Connector key

Good

Core

BadPolarizationAlignment

Measurement of Polarization Extinction Ratio

Adjustment of left-handed and right-

handed cir cular polarization.

handed and right-handed circular

polarization.

45°

A universal measurement and test system for laser beam sources with polarization-maintaining fiber optics

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Vacuum feed-throughs V-... and V-E-...

Casing feed-throughs CFT-... and CFT-E-...

25

26

Fiber Cables: Contents

• Suitable for vacuum down to 10-7 mbar • Wavelength 360 – 2000 nm• Polarization-maintaining, singlemode or multimode fiber cables• Different flange types: small flange KF type and screw-type flange M12 x 1 mm• FC-APC and FC-PC connectors (ST, DIN AVIO, E2000 and F-SMA type connectors available on request)• V-E-...: Vacuum feed-through with connectors with end caps with singlemode and PM-fibers for a redu-

ced power density at the fiber end face

Fundamentals: Fibers Fibers with end caps• Mode field diameter / Numerical aperture NA and NAe2 / Cut-off wavelength• Polarization-maintaining fibers• Fiber attenuation and Brioullin scattering• MFD mismatch / NA mismatch• Fiber cables and fiber connectors• Amagnetic fiber connectors

Singlemode fiber cables SMC-…

Multimode fiber cables MMC-…

Polarization-maintaining fiber cables PMC-...

• Wavelengths 360 – 2000 nm with cut-off wavelengths from 360 to 1300 nm, each with an operational wavelength range of 100 - 500 nm (depending on cut-off wavelength) • Mode field diameter 2.3 – 11 μm

• Special broadband fiber RGBV with an operational wavelength range 400-680 nm• Fiber with low attenuation (Si) for wavelengths <460 nm• FC-APC or FC-PC fiber connector (other connector types available on request)• Amagnetic titanium connectors available for FC-APC or FC-PC connectors • Optionally: Core-alignment

• High OH-/ Low OH- for UV to VIS radiation or VIS to NIR radiation, respectively• FC-APC or FC-PC fiber connector (other connector types available on request)• Amagnetic titanium connectors available for FC-APC or FC-PC connectors• Use for vacuum feed-throughs• Black cable/black buffer available• Application: flatbeam® Laser

• CFT-E-...: Casing feed-through with connectors plus end caps with singlemode and PM-fibers for a reduced power density at the fiber end-face

Fiber optic beam splitter

• Wavelength 460 – 1550 nm, splitting ratio defined for one wavelength• Standard splitting ratio 50:50• FC-APC or FC-PC fiber connectors (ST, DIN AVIO and F-SMA type connectors available on request)• Core alignment• Connecting cable: Ø 3 mm cable with Kevlar strain-relief

2

4

6

8

10

12

14

6.7 μm5.5 μm NA=0.11

NA=0.09

780 nm

MF

D [μ

m]

Components for Photonic Crystal fiber cables PCF-… Fiber cables sold directly by NKT Photonics

• Polarization-maintaining and singlemode fibers with a large mode field diameter and wide spectral range

Laser beam coupler and fiber collimators (also for KineMATIX) available:• FC-APC, FC-PC: laser beam coupler 60SMS-... (page 9) and fiber collimators 60FC-...(page 29ff)• For SMA-905 High Power connector (0°, 5° and 8°-polish): fiber coupler 60FC-SMA-T-...(page 46)© NKT Photonics

17

20

21

22

23

24

27

28

Singlemode fiber cables with end caps SMC-E-…• Singlemode fiber cable with end caps for reduced power density at the fiber end-face• Wavelengths 360 – 2000 nm with cut-off wavelengths from 360 to 1060 nm, each with an operational

wavelength range of 100 - 300 nm • Mode field diameter 2.3 – 11 μm• Special broadband fiber RGBV with an operational wavelength range 400-680 nm• Fiber with low attenuation (Si) for wavelengths <460 nm• FC-APC or FC-PC fiber connector• Amagnetic titanium connectors available for FC-APC or FC-PC connectors

Polarization-maintaining fiber cables with end caps PMC-E-...• Polarization-maintaining singlemode fiber cable with End Caps for reduced power density at the fiber end-face• Wavelengths 360 – 2000 nm with cut-off wavelengths from 360 to 1550 nm, each with an operational

wavelength range of 100 - 300 nm • Mode field diameter 2.3 – 11 μm• Special broadband fiber RGBV with an operational wavelength range 400-680 nm• Fiber with low attenuation (Si) for wavelengths <460 nm• FC-APC or FC-PC fiber connector• Amagnetic titanium connectors available for FC-APC or FC-PC connectors• Polarization aligned to the connector index key

0

• PMC or SMC fibers • customizable delay time • Compact design • FC-APC or FC-PC fiber connectors (ST, DIN AVIO, E2000 and F-SMA type connectors available on request)• Connecting cable Ø 3 mm strain-relief cable • CAS-E-...: Fiber Delay Lines with connectors plus end caps with singlemode and PM-fibers for a reduced

power density at the fiber end-face

Fiber delay lines CAS-... and CAS-E-...

FC adapters without optics and FC mating sleeves (nickel silver or titanium)

• FC fiber adapters are used for connecting fiber cables but have no integrated optics and can be used for telescopes or fiber-coupled spectrometers, according to requirements and customer preferences. Limit stop of fiber ferrule for a reproducible focussing position

• Grub screw for additional locking of the fiber ferrule• Inclined or coaxial coupling axis for fiber connectors of the FC-APC or FC-PC type, respectively (ST, DIN

AVIO, E2000 and F-SMA type connectors available on request)• Optional tilt adjustment for alignment of the coupling axis • Various designs

Fiber optical beam splitter FBS-...

Application:Flatbeam profile

• Wavelengths 360 – 2000 nm with cut-off wavelengths from 360 to 1550 nm, each with an operational wavelength range of 100 - 300 nm • Mode field diameter 2.9 – 12 μm

• Special broadband fiber RGBV with an operational wavelength range 400-680 nm• Fiber with low attenuation (Si) for wavelengths <460 nm • FC-APC or FC-PC fiber connector (other conn. types available)• Amagnetic titanium connectors available for FC-APC or FC-PC connectors• Polarization aligned to the connector index key

gth

m, eacheter 2.9–12 μm

Fibers with

End Caps

Standard fiber

SM-Fiberwith end caps:reduced power density at fiber


Standard fiber

Fiber with End Caps

PM-FiberType Panda

PM-FiberType Panda

PM-Fiber with

End Caps



Standard fiber

ApFlpr

AFp

MultimodeFiber

P hotonicC rystalF iber NNKNKT©©©©© NNNN

sold directly by NKT Photonics

SM-Fiber

SM-Fiber

-Fibere Pandaaananan

ererererererandananaandandand

Standard fiber

Fiber with

End Caps

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1701-2017 E

Figure 1: Different fiber types: Polarization-maintaining singlemode fiber (Most fiber cables from Schäfter+Kirchhoff are of type PANDA), a standard single mode fiber, and a multimode fiber.

Fundamentals: Fibers

The cut-off wavelength co is defined as the shortest wavelength for which the fiber is singlemode. The mode field can only have a Gaus-sian intensity distribution and rotational symmetry above co.If the wavelength of the guided radiation is shorter than the cut-off wa velength, two or more modes are guided. The beam and intensi-ty profile differ significantly from a Gaussian distribution. The mode field distribution depends on bending or temperature variations (butterfly effect).If the operation wavelength is longer than the cut-off wavelength, the guidance of the radiation becomes increasingly weaker. Even a slight bending of the fiber (as well as micro-bends) result in attenua-tion of the guided radiation.The wavelength range in which the fiber operates depends on the fiber parameter and can reach 1.3 times co (Fig 6 A ). The operating wavelength range of fibers with a pure silica core is smaller. When more than one fiber from tables 1 and 2 (pages 20ff) can be used for a particular wavelength, the fiber with a larger cut-off wavelength should be chosen.The measured cut-off wavelength co of a fiber may be 10% less than the nominal value because of manufacturing tolerances. Carefully selected fibers with characterized values are available on request.

Cut-Off Wavelength

Ø50%Ø13.5%

Ø 5%

3

6

24 1

5

SF

Figure 5: Beam profile of a singlemode fiber: definition of numerical aperture NA, NAe2, and mode field diameter MFD

SF

1

2

3

4

5

6

Singlemode fiberCore diameterMFD = mode field ØIntensity level 13.5%Intensity level e.g. 5 % 2 NA (e.g. 5 %)2 NAe2 (13.5 %)

For fiber-coupling purposes an effective fiber NAe2 defined at the 1/e2 level is more convenient than the nominal fiber NA defined by the refractive indices since normally Gaussian beams are defined by their 1/e2 diameter, too.Schäfter+Kirchhoff defines an effective fiber NA which corresponds to the divergence of the power distribution emitted by the fiber taken at the 1/e2 level of the Gaussian angle distribution.This NA value is designated the effective numerical aperture NAe2.For a typical singlemode fiber the value is NAe2 = 0.075.For singlemode fibers and for polarization-maintaining fibers, the effective NAe2 slightly decrease with increasing wavelength .

Effective Numerical Aperture NAe2

The mode field diameter MFD is the diameter of the beam profile on exiting the singlemode fiber. MFD dependends on the wavelength and the effective numerical aperture NAe2 of the fiber accordingly:

2 NAe2 MFD =

Both the MFD, and the effective NAe2 are given at the 13.5 % (1/e2) level of the Gaussian profile. For both, singlemode and polarization-maintaining fibers, the MFD approximately equals the core diameter but is also a function of the wavelength used (Fig. 4).When coupling high power levels, fibers with a larger MFD might be preferred. For fibers with a large MFD (small NAe2), the po wer density within the fiber is reduced and thus the Brillouin threshold is increased. Additionally, in order to prevent the damage of the fiber end faces, fiber onnectors with end caps may be needed, see left.

Mode Field Diameter

Wavelength Dependency of NAe2 and MFD

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Fibers with

End Caps

Standard fiber

SM-Fiber MultimodeFiber

PM-FiberType Panda

erent fiber types: Polarization-maintaining singlem

ss

Schäfter+Kirchhoff obtain fibers from different manufacturers.The fiber manufacturers use the nominal numerical aperture NA of the fibers defined as

NA = nco2-ncl

2

with nco and ncl the refractive indices of fiber core and cladding, respectively.For a typical singlemode or polarization singlemode fiber, the nominal value is NA = 0.12This NA specification corresponds to the Gaussian angle distribution at a 1 % ... 5 % level.

Nominal Numerical Aperture

co

operation range

A

losses due to bending(schematic)

typ. 1.3 co

singlemode

BSchäfter + Kirchhoff HamburgIntensity ProfileLaser Beam Analysis:

Ref.: SK970703 Intensities100.0%

90.0%80.0%70.0%60.0%50.0%40.0%30.0%20.0%10.0%

Object:

Fiber CollimatorCollimating Lens M12Beam Diameter (1/e2) 2.18 mm

Gaussian Fit

C

multimodeFigure 6:Operating wavelength range of a singlemode fiber A

Gaussian mode profile of a singlemode fiber B and C

By using a fiber with a wavelength just below the cut-off wavelength, the multiple modes of the butterfly effect D and E become evident.

In this example: co = 780 nm = 633 nm

D E

Figure 4: Effective numerical aperture NAe2 (left scale)and mode field diameter MFD (right scale) as a function of the wavelength for a PMC-780 fiber

For both singlemode and polarization-maintaining fibers, the numerical aperture NAe2 and mode field diameter MFD may vary by up to 10% from the specified values, simply arising from manufacturing tolerances. Selected fibers with characterized values are available on request.The theoretical coupling efficiency (overlap integral) between two intensity Gaussian distributions is still close to = 1 even when the mode field diameter of an actual fiber differs from the theoretical value.The linear relationship between mode field diameter MFD and numerical apterture NAe2 means this is valid also for a mismatch in

the values for NAe2.

Example: NAe21 = 0.07

NAe22 = 0.08

Overlap: = 0.982

When coupling two fiber cables with NAe2

1/NAe22 =

MFD1/MFD2 < 0.6 then the Schäfter+Kirchhoff 60FF Fiber-Fiber coupler is recom mended.

a = MFD1/MFD

2 = NA

1/NA

2

0.8 0.9 1 1.1 1.20.95

0.96

0.97

0.98

0.99

1

Cou

plin

g ef

ficie

ncy η

Figure 9: MFD Mismatch

MFD Mismatch / NA Mismatch

800 900 1000

0.05

0.06

0.07

0.08

0.09

Wavelength [nm]

NAe2

MFD

1100

7

8

9

10

11

MFD

[μm

]

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Fundamentals: Fibers

Fiber Connectors with End Caps


PM-FiberType Panda

Fibers with

End Caps

Standard fiber

ss

Singlemode and polarization-maintaining singlemode fibers have a core doped with germanium as standard. Short-wavelength radiation interacts with the germanium to produce color centers that cause an increasing non-reversible attenuation of the fiber (solarization effect). For wavelengths <460 nm, Schäfter+Kirchhoff provides singlemode fibers and polarization-maintaining fibers with a pure silica core. These fibers do not demonstrate radiation-induced attenuation and so have a low attenuation that is stable over time.Pure silica core fibers also are more resistant to gamma radiation than Ge-doped fibers.

The attenuation in fibers used for wavelengths below 1550 nm is dominated by Rayleigh scattering and, ad ditionally for wavelengths below 600 nm, by UV absorption. The attenuation is approximately 1 dB/km for = 1000 nm. With decreasing wavelength, the attenuation increases to approximately 20 dB/km for = 460 nm and to approximately 40 dB/km for = 400 nm.When using standard fibers at wavelengths below 460 nm, additional solarization effects worsen the attenuation further. Schäfter+Kirchhoff offer pure silica core fiber cables in order to prevent the problems arising at these lower wavelengths.

Polarization-maintaining singlemode fibers guide coupled radiation in two perpendicular principle states, the fiber polarization axes. For the two polarization axes the speeds of propagation is different, denoted the fast and slow fiber axes.Linearly polarized radiation not coupled exactly into one of these axes is transformed into an elliptical state of polarization because of these different speeds of propagation.The linearly polarized laser radiation is conventionally coupled into the slow axis, because of its lower sensitivity to fiber bending.In polarization-maintaining fibers the rotational symmetry is made void by birefringence. The birefringence is achieved by stress-inducing components in the fiber cladding, such as in “PANDA“ fibers and “Bow-Tie“ fibers or by an oval clad such as in “Oval-Inner Clad“ fibers. The slow axis is orientated in parallel with the stress-inducing elements (“PANDA“ and “Bow-Tie“ fiber) or in parallel with the larger diameter of the inner cladding (“Oval-Inner Clad“ fiber). The polarization-maintaining fiber cables made by Schäfter+Kirchhoff typically use fibers of type PANDA. The slow axis is aligned with the index key of the FC type fiber connector with high precision (<1.5°), see Fig. 7.The fiber cables made by Schäfter+Kirchhoff typically have a polarization extinction >200:1 (23 dB) or >400:1 (26 dB) for >780 nm.

Stimulated Brillouin Scattering is an intense beam effect that limits the maximum power that can be transmitted by the fiber. Unlike photo-contamination and direct scorching of the fiber end-face, which limit the power that can be transmitted at the fiber end-face, the Brillouin effect is a bulk medium effect. The electro-magnetic wave propagating within the optical fiber is scattered by acoustical phonons that are caused by electrostriction. The acoustical phonons induce periodic changes in refractive index (elasto-optical effect) that serve as a Bragg grating, reflecting the incoming radiation. The wavelength of the reflected radiation (Stokes photon) is shifted towards higher wavelengths.If the input power exceeds the Brillouin threshold Pcr , almost the entire radiation is reflected. The threshhold is defined as:

PA

g LCreff

B eff

21 Aeff (MFD)2 = effective core diameterLeff = effective cable length, dependent on fiber lossesgB = gain coefficient of the Brillouin spectrum

The critical power is wavelength-dependent and influenced by other fiber parameters. The amount of power that can be transmitted by a particular fiber needs to be determined for each fiber individually.

Good Alignment: A Bad Alignment:

Connector key axis and slow axis laser polarization axis

Output beam linearly + circularly polarized

Connector key axis = slow axis= laser polarization axis

Output beamlinearly polarized

Figure 8: Attenuation of singlemode and polarization-maintaining fibers (left) and for different fibers according to fiber length (right)

B

00

20

40

60

80

100

Tran

smis

sion

[%

]

Tran

smis

sion

@ 1

m [%

]

Wavelength [nm]350 450 550 650 750 850 9501050

98.6

98.8

99.0

99.2

99.4

99.6

99.8

100

10 20 30 40 50 60

PMC-460

PMC-400Si

PMC-400

Fiber length [m]

Connector index key

Core

Polarization-Maintaining Fibers

Stimulated Brillouin Scattering

Pure Silica Core Fibers (Si)

Fiber Attenuation

Angular offset

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The maximum optical power that can be transmitted by a singlemode fiber is constrained by a number of limiting effects, including stimulated Brillouin scattering SBS and the tweezer effect.

A limiting part of the fiber cable is the fiber end-face, which can be destroyed if the optical power is too high. The maximum power rating depends not only on the cleanliness of the fiber end-face A but also on the power density at the fiber end-face.

Schäfter+Kirchhoff of fers fiber cables with end caps, where the fiber is terminated by a coreless fiber approx. 250 μm long B . Within this section, the radiation is not guided and it diverges up to 10 times the fiber mode field diameter. The power density at the fiber end-face is diminished by a factor up to 100. The numerical aperture of a fiber is not affected by an end cap.

The fiber cables with end caps are assembled identically to the cables with standard fiber connectors of type FC, enabling their use with all 60SMS-... laser beam couplers and all 60FC-... fiber collimators from Schäfter+Kirchhoff.

Working with End Cap fibersBecause of the end caps the emitting point is not at the fiber end face any more. It rather is virtually approx. 180 μm behind the end face.When exchanging a fiber cable without an end cap for a fiber cable with an end cap, the focus position of the laser beam coupler and collimator have to be adjusted.At all 60SMS-... laser beam couplers and 60FC-... fiber collimators the focus setting can be changed.

Figure 7: Axis orientation of a polarization-maintaining fiber with the connector index key

End cap

with End cap

A

B

without End cap

End-face

End-face

Figure 2: Fibers with end caps

Alignment

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Fundamentals: Fiber Connectors


PM-FiberType Panda

Ø 0.9 Ø 3

L1 FC connector for SMC-... fiber

cables only, L1 = 45 mm fiber cable Ø 3 mm,

with Kevlar strain-reliefL2 FC connector for PMC-... fiber cables,

(polarization-maintaining) L2 = 58 mmL3 FC connector (Short) for SMC-... fiber cables, L3 = 25 mm

fiber cable Ø 0.9mm (nylon buffer)L4 FC connector (Short) for PMC-... fiber cables, (polarization-maintaining)

L4 = 39 mm, fiber cable Ø 0.9mm (nylon buffer)

Ø 0.9

Ø 3

L4

Ø 10

.3

L3

Ø10

.3

L2

Ø 10

.3

L1 Ø 10

.3

Fibers with

End Caps

Standard fiber

ss

Singlemode fiber cables made by Schäfter+Kirchhoff are either supplied with a Ø 0.9 mm buffered, Ø 3mm cable with Kevlar strain-relief (Fig. 10 B ) or with only the Ø 0.9 mm buffered component (Fig. 10 A ). Both the cable and the buffering are black.Fibers without buffering (with only a Ø 250 μm coating) can be supplied.

Figure 12: The different fiber cables with their different types of fiber connectors of type FC.

Figure 13: Matched coupling of laser radiation into a singlemode fiber cable and coupling of fiber-guided laser radiation into a collimated beam using fiber connectors of the FC-APC type.Optimal coupling efficiencies are achieved when both the laser beam coupler and the fiber collimator have an inclined coupling axis.

5B

5C

A

FC-PC connector

EC

B D

(8°-polish of the fiber ferrule)

(0°-polish of the fiber ferrule)

FC-APC connector

Singlemode fiber cables made by Schäfter+Kirchhoff are equipped with fiber connectors of type FC-APC or FC-PC. Optionally, they can be provided with fiber connectors of type ST, DIN AVIO, F-SMA, E2000 or with different types of fiber connector at either end. An overview is provided in table 1.All of the fiber connectors of type FC assembled by Schäfter+Kirchhoff have an alignment index (key) of 2.14 mm standard width (or optionally of 2 mm, type “R“).For fiber connectors of type FC-APC, the connector index key is orientated with the 8°-angled polish as shown in Fig. 11 A . (Other orientations can be specified, such as that shown in Fig. 11 B ). The dimensions of the different connectors are shown in Fig. 12.

Fiber coreCladding

Buffer Ø 900 μm

Buffer Ø 900 μm

Kevlar strain-reliefCable Ø 3mm

Coating Ø 250 μm

} Fiber

A B

Because of manufacturing tolerances, fiber connectors may have a misalignment of optical and mechanical axes. Schäfter+Kirchhoff singlemode fiber cables SMC-... (non-polarization-maintaining) can be provided with core alignment (offset 0.5 μm).The connector 60C-FC/FC ensures the direct connection of two fiber connectors with core alignment and a low coupling loss (see page 28). Core alignment is not possible with polarization-maintaining fiber cables.When coupling two polarization-maintaining fiber cables then the Schäfter+Kirchhoff 60FF-... Fiber-Fiber coupler is recommended.

Figure 11: Orientation of the 8°- polish and index key for fiber connectors of type FC-APC: A standard, B optional customized

orientation.

BA

Figure 10: Typical Singlemode fiber cables.

In order to avoid back-reflection directly into the laser source, the fiber in the ferrule of the type FC-APC connector has an 8°-polished face. For fiber cables with this type of connector, Schäfter+Kirch hoff provides fiber collimators (Fig. 13 B ) and laser beam couplers (Fig. 13 D ) with the appropriate inclined coupling axis.If a fiber collimator with coaxial coupling axis is used with FC-APC type connec tors then the beam is obstructed and its profile is distorted, Fig. 13 C .Equally, if a laser beam coupler with coaxial coupling axis is used with FC-APC connectors then the coupling is reduced by about 50%, Fig. 13 D .

Fiber Connectors

Singlemode Fiber Cables PMC-.../SMC-...

Types of Fiber Cables Fiber Cable with Connectors of Type FC-APC

Schäfter+Kirchhoff also offers amagnetic FC-APC and FC-PC fiber connectors with titanium connector mechanics and a ceramic ferrule. This ensures that the relative permeability μr of the connector is near 1 ( =5·10-5, μr=1.00005), making it transparent to magnetic fields.The homogeneity of a magnetic field or the flux lines and absolute value of the defined magnetic field, used in the experiment or application, are not perturbed by the fiber connector.Such highly defined magnetic fields are used for example in Electron Spin Resonance (ESR) or Nuclear Magnetic Resonance (NMR) experiments.Another application of amagnetic fiber connectors is the highly precise measurement of a magnetic field (magnetometer). Here, any perturbation of the magnetic field from magnetic materials close to the setup should be avoided, since they cause disturbances in the magnitude of the determined magnetic field.

Amagnetic fiber connectors

Core Alignment

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sTable 1 Different Connector Types offered by Schäfter+Kirchhoff

TypeSingle-mode fiber

PM-fiber

Multi-mode fiber PC /APC

light, dust-cap

amag-netic

(titanium)

Coup-ling type Remarks

FCx x x x/x x Screw

best suited for most

applications

STx x x/- Bayonet

DIN-AVIOx x x x/x Screw

F-SMAx x x/x Screw

e.g. SMA-905 High Powerconnector

E2000 x x x x/x x Snap

B

• Polarization-maintaining singlemode• Wavelengths 360 – 1800 nm (Cut-off wave lengths from 360 to

1550 nm), each with an operational wavelength range of 100 - 300 nm (depending on cut-off wavelength)

• Mode field diameter 2.9 – 12 μm• Special broadband fiber RGBV with an ope rational wave length

range 400-680 nm• Fiber with low attenuation (Si) for wavelengths <460 nm• FC-APC or FC-PC fiber connector (other connector types available)• Amagnetic titanium connectors available for FC-APC or FC-PC

connectors (p.19)• Polarization direction is indicated by con nector index key

The three defining parameters of a polarization-maintaining single-mode fiber are effective numerical aperture NAe2, mode field diameter MFD and cut-off wavelength co. Because of manufacturing tolerances, the mean specified values for NAe2 and MFD may differ by up to 10%.

Carefully selected fibers with documented values are available on request. Using fibers with end caps reduces the risk of damaging the fiber end face, by reducing the power density but without changing the numerical aperture NA of the fiber.

Polarization-maintaining single-mode fiber cable

Polarization-maintaining single-mode fiber cable with end caps for reduced power density at the fiber end-face, for details see p. 17.

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The PM fibers listed in Table 2 are a small selection of available fibers. Contact Schäfter+Kirchhoff if the required specifi-cations are not listed.All fibers are specified with the measured values for the effectice NAe2 .All PM-fiber cables PMC-... can be equip-ped with an end cap. see p. 18. The NA of the fiber remains the same.

Example: The Connector Type APC.EC/0PC orders a fiber cable with a FC-APC connector with an end cap at one end and a FC-PC connector at the other.

Following connector types are available:AVIO-APC = DIN-AVIO (8°-angled polish)AVIO = DIN-AVIO (0°-polish)E2000-APC = E2000 (8°-angled polish)E2000 = E2000 (0°-polish)

Order Options for PM singlemode fiber cables

cumented values are available ond t d l il bl

h

e

h

e)

Polarization Maintaining Singlemode Fiber Cables PMC-...

Polarization Maintaining Singlemode Fiber Cableswith End Caps PMC-E-...

The three defining parameters of a

Fib

er c

able

s

PM-FiberType Panda

PM-Fiber with

End Caps



Standard fiber

PM fiber type: P = Panda (standard)Length in cm (standard = 150)

PMC - E - 780 - 5.1 - NA012 - 3 - APC.EC/0PC - 150 - P Order Code

Cable type:3 = Ø 3 mm cable with Kevlar strain-relief (standard)1 = fiber cable with Ø 0.9 mm buffer (with FC connector short design)

Nominal Numerical aperture NAMode field diameter MFD at nominal wavelengthNominal wavelength (+Si when stated)

PMC = polarization-maintaining singlemode fiber cable

APC.EC / 0PC.

End cap for 1st fiber end:EC = End cap on this end = no End cap on this endConnector type 1st fiber end: APC = FC-APC (8°-angled polish)0PC = FC-PC (0°-polish)End cap for 2nd fiber end: EC = End cap on this end = no End cap on this endConnector type for 2nd fiber end: APC = FC-APC (8°-angled polish)0PC = FC-PC (0°-polish)For a connector made of Titanium add .Ti

Connector Type: APC = FC-APC (8°-angled polish), both ends 0PC = FC-PC (0°-polish), both ends XPC = one end FC-APC, other FC-PC

row 1 2 3 6 7 8 9 10 11 12 13 14 15

1 Fiber Type PMC-... 360 Si 400 Si 400 Si 400 Si 400 Si 460 Si 460 Si 460 630 Si 630 780 980 980 1300 1550

2 Nom. wavelength nom 360 400 400 400 400 460 460 460 630 630 780 980 980 1300 1550

3 Cut-off wavelength co < 360 < 400 < 400 < 400 < 400 < 460 < 460 < 460 < 630 < 630 < 780 < 980 < 980 < 1300 < 1550

4 Op. wavelength range 360 - 460 400 - 500 400 - 500 400 - 680 400 - 630 460 - 550 460 - 550 460 - 630 630 - 780 630 - 850 780 - 1100 980 - 1550 980 - 1100 1300 - 1600 1550 - 1800

5 Eff. Numerical Aper ture NAe2 (typ.)*

0.08 -0.07

0.08 -0.07

0.06 -0.055

0.07 -0.045

0.09 -0.06

0.08 -0.075

0.06 -0.055

0.08 -0.06

0.08 -0.075

0.07 - 0.06

0.08 - 0.065

0.08 -0.07 0.06 0.08 0.08

6 Mode field dia meter MFD [μm]** 2.9 - 4.2 3.3 - 4.5 4.2 - 5.8 3.8 - 9.5 2.9 - 6.5 3.7 - 4.8 4.8 - 6.1 3.5 - 6.7 4.9 - 6.5 5.5 - 9.0 6.4 - 10.6 8.0 - 14.5 10.8 - 12.3 10.7 - 13.2 12.3 - 14.5

7 Large MFD X X X

8 Pure Silica core X X X X X X X X

9 End caps X X X X X X X X X X X

RGBV RGBV

Fiber NA (nominal)Fiber Type 400Si 400Si 400Si 400Si 460 460 460 630630360Si

NA 0.12 NA 0.12 NA 0.09 NA 0.11 NA 0.15 NA 0.12 NA 0.09 NA 0.12 NA 0.11NA 0.12

780

NA 0.12

980 1300980 1550

NA 0.12 NA 0.11NA 0.085 NA 0.12

1700

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400300

Table 2 PM Singlemode Fiber Cable PMC-... (representative selection)

4.2*

2.9

6.5

2.9

4.8

3.7

6.1

4.8

6.7

3.5

7.4

4.8

9.0

5.5

10.6

6.4

14.5

8.0

12.3

10.8

13.2

10.7

4.5*

3.3

5.8

4.2

9.5

3.8

wa

ve

len

gth

[n

m]

12.3

14.5

E = Cable with end cap fiber connectors Connectors of type FC only

- = Standard fiber connectors

RGBVPM-Fiber

• Wavelengths 360 – 1300 nm with cut-off wave lengths from 360 to 1060 nm, each with an operational wavelength range of 100 - 300 nm (depending on cut-off wavelength)

• Mode field diameter 2.3 – 11 μm• Special broadband fiber RGBV with an operational wave length

range 400-680 nm• Fiber with low attenuation (Si) for wavelengths <460 nm• FC-APC or FC-PC fiber connector (other connector types

available on request)• Amagnetic titanium connectors available for FC-APC or FC-PC

connectors (page 19)• Option: core-alignment

Singlemode fiber cable Singlemode fiber cable with end caps for lower power density at the fiber end face, for details see page 17.

The three defining parameters of a single-mode fiber are effective numerical aperture NAe2, mode field diameter MFD and cut-off wavelength co. Because of manufacturing tolerances, the mean specified values for NAe2 and MFD may differ by up to 10%. Carefully

selected fibers with documented values are available on request. Fiber cables with end caps are available.Please note that unlike the PMC-fiber cables on p. 20 these fibers in general do not preserve the state of polarization.

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460

NA 0.13

alues are available on request. Fiber

Singlemode Fiber Cables with End Caps SMC-E...

Singlemode Fiber Cables SMC-...

S

The three defining parameters of a

SM-Fiber

Standard fiber

Fiber with End Caps

The singlemode fibers listed in Table 3 are a small selection of available fibers. Please con-tact Schäfter+Kirchhoff if the required specifi-cations are not listed. By careful selection, it is possible for Schäfter+Kirchhoff to offer fibers with properties different from those specified by the manufacturer, with a documented MFD and NAe2 as well as particular cut-off and operation wavelengths.All singlemode fiber cables SMC-... can be equipped with an end cap, see page 18. The NA of the fiber remains the same.

Following connector types are available:AVIO-APC = DIN-AVIO (8°-angled polish)AVIO = DIN-AVIO (0°-polish)E2000-APC = E2000 (8°-angled polish)E2000 = E2000 (0°-polish)ST = ST (0°-polish)SMA = F-SMA (0°-polish)

Order Options for singlemode fiber cables

Length in cm (standard = 150)Core Alignment 0 = standard C = core alignment

SMC - E - 780 - 4.7 - NA013 - 3 - APC.EC/0PC - 0 - 150 Order Code

Cable type:3 = Ø 3 mm cable with Kevlar strain-relief (standard)1 = fiber cable with Ø 0.9 mm buffer (with FC connector short design)Numerical aperture NAMode field diameter MFD at nominal wavelengthNominal wavelength (+Si when stated)

SMC = singlemode fiber cable

APC.EC / 0PC.

End cap for 1st fiber end:EC = End cap on this end = no End cap on this endConnector type 1st fiber end: APC = FC-APC (8°-angled polish)0PC = FC-PC (0°-polish)End cap for 2nd fiber end: EC = End cap on this end = no End cap on this endConnector type for 2nd fiber end: APC = FC-APC (8°-angled polish)0PC = FC-PC (0°-polish)For a connector made of Titanium add .Ti

Connector Type: APC = FC-APC (8°-angled polish), both ends 0PC = FC-PC (0°-polish), both ends XPC = one end FC-APC, other FC-PC

E = Cable with end cap fiber connectors Connectors of type FC only

- = Standard fiber connectors

Table 3

1600

1500

1400

1300

1200

1100

1000

900

800

700

600

500

400

300

row 1 2 4 5 6 7 8 9 10 11

1 Fiber Type SMC-... 360 Si 400 Si 400 Si 460 460 Si 530 630 630 Si 780 980 1300

2 Nominal wave-length nom 360 400 400 460 460 530 630 630 780 980 1300

3 Cut-off wavelength co < 360 < 400 < 400 < 460 < 460 < 530 < 630 < 630 < 780 < 980 < 1300

4 Operation. wavelength range 360 - 470 400 - 550 400 - 680 460 - 600 460 - 600 530 - 700 630 - 770 630 - 860 780 - 970 980 - 1550 1300 - 1650

6 Eff. Numerical Aper ture NAe2(typ.)*

0.095 - 0.08

0.08 -0.07

0.07 -0.05

0.085 -0.07

0.08 -0.07

0.095 - 0.08

0.085 -0.075

0.08 - 0.07 0.085 0.09 -

0.07 0.08

5 Mode field diameter MFD [μm]** 2.4 - 3.8 3.2 - 5.0 3.5 - 8.8 3.5 - 5.4 3.7 - 5.4 3.5 - 6.3 4.8 - 6.6 5.0 - 6.9 5.5 - 7.4 7.7 - 13.8 10.2 - 13.3

7 Pure Silica Core x x x x x

8 End caps x x x x x x x x

RGBV

Singlemode Fiber Cable SMC-...(representative selection)

wa

ve

len

gth

(n

m)

3.1*

2.3

5.4

3.5

5.4

3.7

6.6

4.8

7.6

5.0

7.4

5.5

13.8

7.7

13.3

10.2

8.8

3.5

5.1

3.2

3.7

4.9

Fiber NA (nominal)Fiber Type 360Si 400Si 400Si 460Si 530 630 780630Si 980

NA 0.12 NA 0.12 NA 0.12 NA 0.12 NA 0.11 NA 0.13 NA 0.13NA 0.12 NA 0.14

* Definition see p.17** Calculated from the NAe2 and the wavelength Si For wavelengths <460 nm,

Schäfter+ Kirchhoff provides singlemode fiber cables with extra low attenuation that have a pure silica core and are devoid of solarization effects, see page 18.

RGBV is a singlemode fiber suit able for the entire visible wavelength range of 400 - 680 nm. It is used mainly in combination

with the apochromati cally corrected laser beam coupler from Schäfter+Kirchhoff, see p. 10 + 51.

RGBVSM-Fiber

1300

NA 0.11

SM-Fiberwith end caps:reduced power density at fiber


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Polarization Maintaining Singlemode Photonic Crystal Fibers PCF-... (Fiber cables sold directly by NKT Photonics)

Beam profile© NKT Photonics

Fib

er c

able

s

• Polarization-maintaining and singlemode fibers• Relatively large mode field diameter and wide spectral range• FC-APC, FC-PC, SMA-905 High Power Connector (NKT Photonics) (0°, 5° and 8°-polish)• Laser beam coupler and fiber collimators (also for kineMATIX) available for all connector

types• Fibers sold directly by NKT PhotonicsPhotonic Crystal Fibers (PCF) cover a range of fiber types and include hollow core fibers, polarization-maintaining Large Mode Area fibers (LMA-PM), singlemode Large Mode Area fibers (LMA) and highly nonlinear or highly dispersive photonic crystal fibers. They differ in fiber specifications and are suitable for a wide range of applications.Those photonic crystal fibers optimized for singlemode operation have a wide spectral range combined with a relatively large mode field diameter, enabling them to transmit high optical powers. Being made from fused silica, they are resistant to solarization effects. The mode field diameter for LMA-fibers is almost wavelength-independent, whereas the numerical aperture NA depends on the wavelength (Fig. 2). The specific arrangement of vacuities in the photonic crystal cladding (Fig. 1) results in a beam profile with a hexagonal shape that only approximates a Gaussian.A selection of different types of photonic crystal fibers is available, all manufactured and sold directly by NKT Photonics: http://www.nktphotonics.com.


Sp

ec

tra

l r

an

ge 1100

380

750

640

540

400

PM-Fiber

Figure 2. Wavelength-dependence of mode field diameter and numerical aperture for a LMA-PM-fiber.

Figure 1. Structure of a polarization-main taining Large Mode Area fiber.

The photonic crystal fiber micro structure of a singlemode polarization-main taining Large Mode Area fiber exhibits a hexagonal pattern with stress rods inducing birefringence. The major benefits include a larger mode field diameter and a wider spectral range for singlemode ope ration. wavelength [nm]

NA

MF

D [μ

m]

The mode field diameter for LMA-fibers is almost wave-length-independent, whereas the numerical aperture NA is wavelength-dependent.This must be considered when choosing the most appropriate laser beam coupler or fiber collimator.

0.06

0.08

0.1

0.12

0.14

0.16

3

3.5

4

4.5

5

5.5

350 450 550 650 750 850


Fiber Optic Components suitable cure Photonic Crystal Fibers

... with FC-APC or FC-PC connector

Fiber collimator 60FC-Q-... / 60FC-E-... (p. 42f)Generation of circulary polarized laser radiation with integrated quarter-wave plate

Beam profile: circular

Beam profile: elliptical

Fiber collimator 60FC-T-...(p. 36)

Laser beam coupler 60SMS-..., see p. 9

Fiber collimator 60FC-... (p.33)

Fiber Collimator 60FC-K-...compatible with KineMATIX opto-mechanics

... with SMA-905 High Power Connector


Multiline

Laser Source

inclined fiber coupling axis

Fiber collimator 60FC-K-...,see page 44

Tilt adjustment

©N

KT

Pho

toni

cs

Fiber collimator 60FC-SMA-...with integrated tilt adjustment (page 46)

Beam Profile

Polarization Analyzer series SK010PA-...

• USB 2.0 interface • Multiple wavelength

ranges 350 – 1600nm

For further information, see page 71

• Designed for SMA-905 High Power Connectors with 0°, 5° and 8°-polish

• Suitable for High Power applications

• Large variety of optics

• Flexible interchange of fiber cables

• Focussing of the optics• Large variety of optics,

partly achromatic or apochromatic (RGBV)

• Use of fibers with end caps

Adjustable Quarter-wave plate

Adjustment of left-handed and right-

handed cir cular polarization.

45°

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The MM fibers listed in Table 6 are a small selection of available fibers. Please contact Schäfter+Kirchhoff if the required specifications are not listed. By careful selection, it is possible for Schäfter+Kirchhoff to offer fibers with defined proper-ties that can differ from those specified by the manufacturer.

Order options for multimode fiber cables MMC-...

Multimode fiber cables MMC-...

• Multimode• High OH- for UV and VIS transmission and Low OH- for VIS and NIR radiation• FC-APC or FC-PC fiber connector (other connector types available on request)• Amagnetic titanium connectors available for FC-APC or FC-PC connectors

(for details see page 19)• Use for vacuum feed-throughs• Black cable/black buffer available

MultimodeFiber F

iber

cab

les

While common singlemode fibers have a step-index profile for the refractive index, there are two types of multimode fibers: step-index and gradient-index. Step-index fibers have a step profile with one refractive index n2 for the core and one for cladding (refractive index n1) throughout the fiber. The core diameter of a multimode fiber is rather large (>50 μm), allowing multiple modes of light guidance. A gradient-index fiber exhibits a gradual profile (almost parabolical in shape) for the refractive index, which results in a smaller modal dispersion because of the approximately sinusodial beam propagation along the fiber.

n1

n2

Step Index

n1

n2

ngGradientIndex

Gradient index vs. step index in Multimode Fibers

Table 4 Fiber Collimators for Multimode fibers MMC-... (Selection from tables 1–6 on pages 33–36)Fiber Collimators 60 FC-... Fiber Collimators 60FC-T/ 60FC-L

row curr. no 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 171 Lens type A2.7 A3.1 M3.1 A4 A4.5S M5 A6.2S A7.5 A8 A11 M11 M12 M20 L M25 M30 M40 L M1002 Focal length f' 2.75 3.1 3.1 4 4.5 5.1 6.16 7.5 8 11 11 12 20 25 30 40.0 1003 Numerical aperture NA 0.55 0.68 0.25 0.6 0.42 0.25 0.3 0.3 0.3 0.25 0.23 0.23 0.17 0.23 0.22 0.30 0.244 Clear apert. max. [mm] 3.6 5 1.7 5 3.7 2.5 3.7 4.5 4.9 5.5 5 5.5 6.8 13 13 24 485 Correction - achrom. x x x x x x x x Spectral range Code no. of AR coating *IR chalcogenide lens6 350 - 460 nm 52 52 52 527 400 - 600 nm 01 01 01 01 01 01 01 01 01 01 01 01 018 600 - 1050 nm 02 02 02 02 02 02 02 02 02 02 02 02 029 1050 - 1550 nm 03 03 03 03 03 03 03 03 03 03 03

10 1300 - 1750 nm 45 45 45 45 45 4511 1750 - 2150 nm 09 09 09 09 0912 390 - 670 nm 33 33 3313 630 - 980 nm 10 10 1014 980 - 1550 nm 08 08 0815 420 - 700 nm 26 26 2616 750 - 1550 nm 37 37 37 3717 400 - 670 nm 51 5118 520 - 830 nm 1819 650 - 1150 nm 07 0720 1750 - 3000 nm 64 64*21 450 - 700 nm 04 04 04 04 04

Table 5 Multimode Fiber Cable MMC-...

row 1 2 3 4 5 6 7 8 9

1 Fiber Type G S S S S S S S S

2 Core diameter [μm] 62.5 50 50 105 105 200 200 300 300

3 Num. aperture NA [μm] 0.27 0.22 0.22 0.22 0.22 0.22 0.22 0.22 0.22

4 UV/VIS (High OH-) x x x x

5 VIS/NIR (Low OH-) x x x x x

6Suitable for vacuum feed- throughs V-...

x x x x x x x

G = Gradient-index fiber S = Step-index fiber

Please note that the beam profile emitted by a multimode fiber is not Gaussian.Fiber-fiber coupling from a multimode to a singlemode fiber is non-functioning.

cable type:3 = Ø 3 mm cable with Kevlar strain-relief (standard)1 = fiber cable with Ø 0.9 mm buffer (with FC connector short design)Numerical aperture NA

MMC-S-VIS/NIR-50-NA022-3-APC-150

Core Diameter Wavelength range UV/VIS = High OH-, for UV or VIS radiationVIS/NIR = Low OH-, for VIS or NIR radiation

Length in cm (standard = 150)Order Code

Connector Type:APC = FC-APC (8°-angled polish), both ends0PC = FC-PC (0°-polish), both endsXPC = one end FC-APC, other FC-PCFor a connector made of Titanium (Only for fibers No. 1–5, amagnetic, page 19) add .Ti

Following connector types are also available: (more on request)• AVIO-APC =DIN-AVIO (8°-angled polish)• AVIO = DIN-AVIO (0°-polish)• E2000-APC = E2000 (8°-angled polish)

• E2000 = E2000 (0°-polish)• ST= ST (0°-polish)• SMA = F-SMA (0°-polish)

MMC fiber type:S = Step index G = Gradient indexMMC = Multimode fiber cable

The collimating lens can be adjusted to generate a focussed beam. At distance A, relative to the fiber collimator, a beam waist with diameter Øspot is formed.

The beam diameter ØBeam is given by the focal length of the collimating lens f‘ and by the numerical aper-ture NA of the multimode fiber.

Beam f NA2 '

The beam always shows divergence due to the finite core diameter d. The divergence angle is defined as:

It is important that the numerical aperture of the chosen lens is higher than the numerical aperture of the multimode fiber. Table 4 shows some appropriate collimating lenses.

Øbeam

f ’

Øspot Øbeam

A

SpotAf '

1

d/2f

Collimating the beam

Focussed laser beam

Typical Spectra for UV/Vis or Vis/NIR Multimode fiber cables

Øspot : Beam diameter in focusA : Working distance f ’ : Focal length of collimating lens

200 600 1000 1400 1800 2200

103

102

10

UV/VIS: High OH-

VIS/NIR: Low OH-atte

nuat

ion

[dB

/km

]

Fiber-Optic Beam Splitters FBS-...

Fiber-optic beam splitters A split the radiation guided in a singlemode fiber into two singlemode fibers. Fiber-optic beam splitters from Schäfter+Kirchhoff have a splitting ratio up to 1:99 and are provided for wavelengths between 460 and 1500 nm. The bandwidth is within ±1% of the designed wavelength and inser tion loss is approximately 1 dB at 460 – 700 nm and 0.5 dB at 700 – 1550 nm.

The fiber-optic beam splitters have 3 or 4 ports and are ideal for use in interferometric or other setups. The Ø 3 mm cables have Kevlar strain-relief and the connectors may be of type FC-PC, FC-APC (or ST, SMA, E2000 or DIN-AVIO) or core-aligned (<0.5 μm). Customized products, such as with a different number of output ports, are available on request.

Fused biconical taper X

Y

SM-Fiber

Special Configurations of Fiber-Optic Beam Splitters FBS-...

Fiber-optic beam splitter FBS-... with vacuum feed-through V-...

Fiber optic beam splitter FBS-... with casing feed-through CFT-...

Schäfter+Kirchhoff also offer fiber-optic beam splitters in direct combination with vacuum feed-throughs B (for more details see page 27), that can be attached to any port, as required. The feed-throughs are sui table for vacuums down to 10-7 mbar and are supplied with either a small flange KF16 (DIN 28403) (option: KF40/KF50) or a screw-type flange

(M12 x 1 mm). The connectors may be of type FC-PC, FC-APC (or ST, SMA, E2000 or DIN-AVIO), although not all of these connectors are suitable for a vacuum.Please contact Schäfter+Kirchhoff for more information.

Fiber-optic beam splitters can also be equipped directly with casing feed-throughs at any port C (for more details see page 26).

Inside the casing, the fiber cables are 900 μm buffered and, outside the casing, the cable is 3mm in diameter and has Kevlar strain-relief.

The connectors can be of type FC-PC, FC-APC (or ST, SMA, E2000 or DIN-AVIO).

Please contact Schäfter+Kirchhoff for more information.

B

C

Fib

er c

able

s

A

FBS - 630 - X – 50/50 – APC/APC - 0 – 100/100

Cable length in cm (in/ out)

Core Alignment 0 = standard c = Core Alignment (SMC only)

Fiber connection (in/ out): APC = FC-APC (8°-angled polish) OPC = FC-PC (0°-polish) For a connector made of Titanium (amagnetic, page 19) add .Ti

Splitting ratio

Number ports: X = 4-Port Y = 3-Port

Nominal wavelength

FSB = fiber optic beam splitter

Order Code Please contact Schäfter+Kirchhoff for other fiber-optic beam splitter requirements.

Following connector types are also available:

• AVIO-APC =DIN-AVIO (8°-angled polish)• AVIO = DIN-AVIO (0°-polish)• E2000-APC = E2000 (8°-angled polish)• E2000 = E2000 (0°-polish)• ST= ST (0°-polish)

• ST= ST (0°-polish)

• SMA = F-SMA (0°-polish)

Order Options for Fiber-optic Beam Splitters FBS-...

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Order optionsfor Vacuum feed-throughs

DimensionsDi i s

VacuumFeed-Throughs V-...

VacuumFeed-Throughs with End Caps V-E-...

The fiber cables with vacuum feed-through made by Schäfter+ Kirchhoff are equipped with single-mode fibers, polarization-maintaining singlemode or multi-mode fibers for wave lengths from 360 to 1800 nm (in case of singlemode: cut off wavelengths 360 nm - 1550 nm with a bandwidth up to 300 nm)

For the available fiber and connector types, see Tables 1, 2 and 3.

The feed-throughs are sui table for vacuums down to 10-7 mbar and are supplied with either a small flange KF16 (DIN 28403, stainless steel) D or a screw-type flange (M12 x 1 mm, nickle silver) E .

Also available are multiple fiber cable feed-throughs with flange type KF40 or KF50. Arbitrary fiber cable types can be combined in one flange.On the vacuum side, the fiber cables have a Ø 900 μm buffer made of Hytrel. Outside the vacuum, there is a Ø 3 mm cable with Kevlar strain-relief at the fiber connector and at the flange.

For vacu um feed-throughs with single-mode fibers, the connector away from the vacuum can be core-aligned as an option (<0.5 μm).Singlemode and polarization maintaining fiber cables can be equipped with end caps on one or both ends in order to reduce the power den-sity at the fiber end-face (see V-E-..., right hand side).

In (vacuum-side):

• AVIO-APC =DIN-AVIO (8°-angled polish)

• AVIO = DIN-AVIO (0°-polish) • ST= ST (0°-polish) • SMA = F-SMA (0°-polish)

Out (non-vacuum side):

• AVIO-APC =DIN-AVIO (8°-angled polish)

• AVIO = DIN-AVIO (0°-polish) • E2000-APC = E2000 (8°-angled

polish) • E2000 = E2000 (0°-polish) • ST= ST (0°-polish)

** Following connector types are also available:

Screw-type flange (M12 x 1 mm)

Small flange KF16 (DIN 28403)

D

Flange type KF50available with 2, 3, or 4 fiber cables of arbitrary type

FC connector FC connectorVacuum

Flange type KF40available with 2, 3, or 4 fiber cables of arbitrary type

Standard fiber

Fiber with End Caps

SM-Fiber PM-Fiber

* One value = same connector type on both endsFor fiber specifications please see fiber tables 1, 2, pages 20-23.

Singlemode/PM: Nominal cut off wavelengthMultimode: Wavelength range UV/VIS or VIS/NIR

Fiber type:

Order Code

SMC = singlemode fiber cablePMC = polarization-maintaining fiber cableMMC = multimode fiber cable

V-SF - PMC - 780 - 5.1 - NA012 – APC/0PC – 0 -30/120 – P PM only: fiber type (see fiber Table 1 )

Cable length in cm ( in = vacuum side / out )*

Core Alignment 0 = standard (singlemode only)

Fiber connection ( in / out )*/**:

Connector type outside vac.:

APC = FC-APC (8°-angled polish) 0PC = FC-PC (0°-polish)

Fiber connectors with end caps: APC.EC = End cap on FC-APC 0PC.EC = End cap on FC-PC

Connector type inside vac.: APC = FC-APC (8°-angled polish) 0PC = FC-PC (0°-polish)

Fiber connectors with end caps: APC.EC = End cap on FC-APC 0PC.EC = End cap on FC-PC For a connector made of Titanium

(amagnetic, page 19) add .Ti

APC / 0PC

Numerical aperture NA

Singlemode/PM: Mode field diameter MFD Multimode: Core diameter

Multiple Cable Feed-Throughs

FC connector Vacuum FC connector

Flange type: V-KF16 = Vacuum feed-through with small flange KF16 (optional: KF40, KF50)V-E-KF16 = As above but fiber cable with end capsV-SF = Vacuum feed-through with screw flange M12x1mmV-E-SF = As above but fiber cable with end caps

SM-Fiber PM-FiberMM-Fiber


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Application Application

Casing Feed-Throughs CFT-...

Casing Feed-Throughs with End Caps CFT-E-...

Standard fiber

Fiber with

End Caps

• AVIO-APC =DIN AVIO (8°-angled polish)

• AVIO = DIN AVIO (0°-polish)• E2000-APC = E2000

(8°-angled polish)


** Following connector types are also available:

FC connector FC connector

inside the casing outside the casing

The fiber cables with casing feed-through made by Schäfter+ Kirchhoff are equipped with single-mode fibers, polarization-maintaining singlemode or multi-mode fibers for wave lengths from 360 to 1800 nm (in case of singlemode: cut off wavelengths 360 nm - 1550 nm with a bandwidth up to 300 nm)

For the available fiber and connector types, see Tables 1, 2 and 3.

Inside the casing, the fiber cables have a Ø 900 μm buffer made of Hytrel. Outside the casing, there is a Ø 3 mm cable with Kevlar strain-relief at the fiber connector and at the flange.

The cable feed-through CFT-... is installed by threading the outside part of the cable through an aperture from the inside of the casing.

For casing feed-throughs with singlemode fibers, the outside connector can be core-aligned (<0.5 μm) as an option.

Singlemode and polarization maintaining fiber cables can be equipped with end caps on one or both ends in order to reduce the power density at the fiber end-face (see CFT-E-..., right hand side).

* One value = same connector type on both endsFor fiber specifications please see fiber tables 1, 2, pages 20-23.

Order Code CFT - PMC - 780 - 5.1 - NA012 – APC/0PC – 0 -30/120 – P PM only: fiber type (see fiber Table 1 )

Cable length in cm ( in = vacuum side / out )*

Core Alignment 0 = standard (singlemode only)

Fiber connection ( in / out )*/**:



For a connector made of Titanium (amagnetic, page 19) add .Ti

Numerical aperture NA

Singlemode/PM: Mode field diameter MFD Multimode: Core diameter

Singlemode/PM: Nominal cut off wavelength Multimode: Wavelength range UV/VIS or VIS/NIR Fiber Type: SMC = singlemode fiber cable PMC = polarization-maintaining fiber cable MMC = multimode fiber cable

APC / 0PC

Flange type: CFT = Casing feed-throughCFT-E = As above but fiber cable with end caps

PM-FiberSM-Fiber


Order optionsfor Vacuum feed-throughs

DimensionsFi

ber

Cab

le_V

acuu

m-e

tc_S

24-2

8.in

dd

• P

age

26


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Order options for delay line with end caps

Fiber Delay Lines CAS-...

Fiber Delay Lines with End Caps CAS-E...

Singlemode and PM-fiber cables for Fiber Delay Lines can be equip-ped with an end cap on one or both ends. The mode field is expanded at the fiber end-face by a factor up to 10. The risk of damaging the fiber end-face because of high optical power is reduced, see page 18. The NA of the fiber remains the same.

Fiber cables can be used as optical delay lines. The group delay

g ( ) of a singlemode fiber is given by:

where

for the effective refractive index neff ( ).

As a good approximation, the effective refractive index of the singlemode fiber neff ( ) is practically the same as that of the core material, ncore ( ). The group delay for this approximation is shown in for a fiber with NA 0.11 for 400 – 1000 nm F .

Schäfter+Kirchhoff offers singlemode fibers and polarization-maintaining fibers with lengths >20 m, also spooled in compact cassettes. The two fiber ends are provided pigtailed with Ø 3 mm cabling, with strain-relief and fiber connectors.

l ng( )cg( ) =

dneff ( )dng( ) = neff ( ) -

Order Code CAS - PMC-780-5.1-NA012-APC.EC/0PC-0-10000-150/150-P

PM only: fiber type (see fiber Table 1)

Pigtail length in cm ( in / out )*

Fiber lengths in cm Core Alignment 0 = standard Fiber connection ( in / out )*/**:



For a connector made of Titanium (amagnetic, page 19) add .Ti

Numerical aperture

Mode field diameter MFD Nominal wavelength Fiber type: PMC = polarization-maintaining fiber cable SMC = singlemode fiber cable MMC = multimode fiber cable

CAS = Fiber Delay Line CAS - E = Fiber Delay Line with end cap connectors

**The following connector types are also available:

• AVIO-APC =DIN-AVIO (8°-angled polish)• AVIO = DIN-AVIO (0°-polish)• E2000-APC = E2000 (8°-angled polish)

For fiber specifications please see fiber tables 1 and 2, pages 20–23.


* only one value = the same at both ends

APC.EC / 0PC.

42TE/ 213.2 168 2.5

208.6

3HE

/ 12

8.4

400 600 800 10004.85

4.9

4.95

5.0

5.05

5.1

Wavelength λ [nm]

Gro

up d

elay

τ[n

s/m

]

Standard fiber

Fiber with End Caps

SM-Fiber PM-Fiber


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4x M2

Ø20

3Ø16

Ø 9

4x M2

Ø20

3Ø16

Mating sleeves provide an uninterrupted physical contact between two singlemode fiber cables SMC-... with core-centering. Two connectors

of type FC-PC (0°-polish) or of type FC-APC (8°-polish) can be connec-ted.

Mating sleeves for two FC connectors (panel mount, wide key ):

Order Code

Order Code

25AM-4-FCFC-APC adapter

25AM-0-FCFC-PC adapter

Order Code

Order Code

25AF-4-FCFC-APC adapter

25AF-0-FCFC-PC adapter

Order Code

Order Code

12AF-4-FCFC-APC adapter

12AF-0-FCFC-PC adapter

Order Code

Order Code

19.5AC-4-FCFC-APC adapter

19.5AC-0-FCFC-PC adapter

Order Code

Order Code

19.5AC-4-FC-TiFC-APC adapter

19.5AC-0-FC-TiFC-PC adapter

Order Code

Order Code

10AF-4-FC+PP1020-TiFC-APC adapter

10AF-0-FC+PP1020-TiFC-PC adapter

Order Code

Order Code

12AF-4-FC-TiFC-APC adapter

12AF-0-FC-TiFC-PC adapter

Order Code

Order Code

10AF-4-FC+PP1020FC-APC adapter

10AF-0-FC+PP1020FC-PC adapter

60C-FC/FC

Order Code

60C-FC/E2000

Order Code

FC Mating Sleeves

15

Ø2,

2

Ø9

9,5

15

4.95.95

221813

6.5

28.45

FCCT01

Order Code

Accessory: Fiber Connector Cleaning Tool FCCT01

The Fiber Connector Cleaning tool FCCT01 from Schäfter+ Kirchhoff is a cloth cleaning tool (more than 500 cleanings per unit) specially designed for cleaning fiber connectors of type FC-PC and FC-APC. It is highly effective at removing contaminants from the fiber end-face, restoring the optical performance.

FC fiber adapters are used either for beam outputs, where no collimation or focussing of the beam is necessary, or for beam coupling to fiber connectors but without integrated optics, such as when microscope optics are used. Schäfter+Kirchhoff FC fiber adaptors have a fiber connection with an inclined coupling axis for use with fiber connectors of the FC-APC type or a fiber connection with co axial coupling axis for use with fiber connectors of the FC-PC type, both wide-key (optionally: ST, DIN AVIO, or F-SMA).

Other performance features include: • Axial stop of the fiber ferrule for a constant focus position, especially

for fiber adapters with an inclined coupling axis• Grub screw for an additional locking of the fiber ferrule• Integrated tilt adjustment for alignment of the coupling axis• FC fiber adapter with tilt adjustment and integrated quarter-wave

plate for generating circularly polarized radiation.

Application: magneto-optical traps (see www.sukhamburg.com/pdf/art_mot_e.pdf)

FC Fiber Adapters without Optics

Application:

Chromatically corrected microscope lenses

Ø 9

FC fiber adapters are used either for beam outputs, where no collimation or focussing of the beam is necessary, or for beam coupling to fiber connectors but without integrated optics, such as when microscope optics are used. The general performance features are described above. Fiber adapters made of titanium possess special features. Titanium has

a low thermal expansion, has a high resistance to environmental effects and is suited for use in a vacuum. The amagnetic properties allow its use in environments with highly defined magnetic fields. The relative permeability near 1 ensure that adapters made from titanium are almost transparent for the magnetic field.

FC Fiber Adapters without Optics made of Titanium

Fib

er c

able

s

12AF-... compact design with Ø12 mm diameter. Interior varnished in matt black.

19.5AC-... FC adapter with tilt adjustment for aligning the axis of the emitted radiation. With standard adapter flange Ø19.5 mm.

19.5AC-...-Ti FC adapter with tilt adjustment for aligning the axis of the emitted radiation. With standard adapter flange Ø19.5 mm.

10AF-...-Ti FC adapter as OEM version with bearing flange.Application: Simultaneous fiber coupling of different

laser sources by use of chromatically corrected lenses in fluorescence microscopy.

12AF-...-Ti compact design with Ø12 mm diameter. Interior varnished in matt black.

10AF-... FC adapter as OEM version with bearing flange.Application: Simultaneous fiber coupling of different laser sources by use of chromatically

corrected lenses in fluorescence microscopy.

25AF-... FC adapter with Ø25 mm fit for microbench system e.g. for collimators with long focal length.

25AM-... FC adapter with Ø25 mm fit for micro-bench system with integrated tilt adjustment for aligning the axis of the emitted radiation

Hybrid adapter for joining connector type E-2000 to connector type FC (panel mount):

Fiber-fiber couplers 60FF-... see page 63

FC-APC adapterwith bearing flange

10AF-X-FC + PP1020

FC

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polarization-maintaining fiber cables pmc- singlemode ... · pdf filefiber optic accessories...

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