construction kit "multicube" 48mc- - sch¤fter + kirchhoff gmbh

multicube™ – Components and Systems for the rugged and compact implementation of a wide range of different setups.

71

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multicube™ – Components and Systems

Construction Kit multicube™ 72

Combination Cubes and Plates 48MC 73

Optics for the multicube™ System 74

Accessories: Flanges, and Adapters 77

Accessories and Tools 78

Titanium Components - Amagnetic Multicube™ Elements 79

Faraday Isolators 82

Fiber-coupled Faraday Isolator 83

Laser Attenuators 48AT 84

Electro-Magnetic Shutter 85

Fiber-Optical Solutions 86

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The major design features of the Schäfter+Kirchhoff multicube™ components ensure highly rugged and warp-resistant setups, especially for single-mode fiber coupling. The multicubes™ are combined and fixed using four Ø 6 mm rods in parallel and are compatible with established microbench systems. The multicube™ construction system is the perfect integration platform for laser beam couplers, beam combiners, beam splitters, polarizers or retardation optics. Self-supporting modules and laser beam assemblies can be created that are extremely resistant to torsion and contain complementary components, such as the laser diode collimator 48TA and Faraday iso lator 48FI on the mounting bracket 48MB.

The multicube™ system is compatible with the established cage system and the microbench system

Applications: see the laser diode beam sources 48TE, and fiber port clusters for magneto-optical traps (MOTs) on page 90.

Construction Kit multicube™ Series 48MCcompatible with established cage and microbench systems

Implementation of an essentially limitless range of setups: Examples

Fiber Port Cluster: 2 6

This unit splits the radiation from two polarization-maintaining (PM) fibers into 6 output polarization-maintaining fiber cables with high efficiency and variable splitting ratio.

The beam delivery system uses the compact, modular opto-mechanic units of the multicube system.

The modularity ensures that almost any desired system can be assembled that is compact and sealed.

For more details see page 91.

Fiber Port Cluster: 1 4

This unit splits the radiation from one polarization-maintaining (PM) fiber into 4 output polarization-maintaining fiber cables with high efficiency and variable splitting ratio.

For more details see page 92.

Fully assembled and pre-aligned(fibers not shown)

Schematic drawing of optics components used

Schematic drawing of optics and mechanical components

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Combination Cubes and Plates 48MCcompatible with established cage and microbench systems

Order Code

48AT-A

Order Code

48MC-LT-19.5

Double-Cube with through-holes for linear arrangements

Mechanical Attenuatorwith fine thread, aperture Ø 3 mm, system mount Ø 19.5 mm

Double-T-Cubefor T-arrangements

Order Code

48MC-LTD-19.5

Order Code

48MB-19.5-150

Order Code

48MC-CL-19.5

Single-X-Cubefor X-arrangements

Triple-X-Cubefor X-arrangements

Single-Cubewith through-holes for linear arrangements, short design

Mounting Platefor mounting Ø 19.5, 25 or 32 mm system components

Extended Mounting Plate for mounting Ø 19.5 or 25 mm system components

Mechanical Shutteraperture Ø 3 mmsystem mount Ø 19.5 mm

Order Code

48MC-SM-19.5

Order Code

48MC-MP-19.5 48MC-MP-25 48MC-MP-32

Single-T-Cubefor T-arrangements

Order Code

48MC-LTS-19.5

Order Code

48AT-S

Order Code

48MC-SP-19.5 48MC-SP-25

Extended Mounting Bracket 150 x 60 mm or 60 x 60 mm, system mount Ø 19.5 mm

Dimensions

Dimensions

Dimensions

Order Code

48MC-LI-19.5

Order Code

48MB-19.5-SXY-1

x/y Adjustment platefor lateral adjustment, translation 1 mm

8

Order Code

48MB-19.5-150

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Optics for the multicube™ System

Beam-splitting cube with internal dielectric and polarizing multilayer coating. Adjustable mount, for mounting with clamp collar (included).50:50 split ratio for linearly polarized input radiation with polarization direction = 45°. Maximum transmission at = 0° ( p-pol.) with maximum reflection at = 90° (s-pol.).

Polarization Beam Splitters 48PM-CC

Beam Splitter Cubes 50/50 48BM-CC

Spectral range [nm]A = 450 - 700 nmB = 750 - 1100 nmC = 1100 - 1700 nm

48BM - CC - AOrder Code

With adjustable mount, for mounting with clamp collar (included).

Spectral range [nm]A = 450 - 700 nmB = 750 - 1100 nmC = 1100 - 1700 nmW= 450 - 1000 nm

48PM - CC - AOrder Code

Order Options for Polarization Beam Splitters

Application: Beam splitter with adjus table splitting ratio, in combination with retardation optics 48WP-CA

Beam Splitter and Beam Combiner, Polarizer, Retardation Optics

• Extinction ratio 10 000 : 1• Clear aperture 6 mm • Reflection angle 90°• Broadband AR coating R < 0.5 % per surface

With adjustable mount, for mounting with clamp collar (included).

Beam Splitters 98/2 48BS-CC-A

Beam Splitters 99/1 (10/90) 48BS-CC-B

48BS - CC - AOrder Code

Order Options for Beam Splitters 98/2

48BS - CC - BOrder Code

Order Options for Beam Splitters 99/1 (10/90)

Application: Separation of a partial beam for power monitoring

• 1 mm fused silica plate, uncoated• 0.3° wedge angle for interference suppression• Transmission 98 % ( p-polarization)• Reflection 1 % per surface ( p-polarization)• Clear aperture 10 mm

• 1 mm fused silica plate, rear side coated (AR 400 - 700 nm)• 0.3° wedge angle for interference suppression• Reflection 1 %, transmission 99 % ( p-polarization)• Reflection 10 %, transmission 90 % ( s-polarization)• Clear aperture 10 mm

Order Options for Beam Splitter Cubes 50/50 48BM-CC

In adjustable mount, for mounting with clamp collar (included).

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Edge wavelength [nm]

48BC - CC - LP xxxOrder Code

Order Options for Beam Combiner 48BC-CC-LP

Reflection long pass Transmission Pol.LP436 370 - 412 460 - 700 sLP510 405 - 488 532 - 660 sLP570 532 - 544 594 - 660 sLP580 500 - 560 600 - 700 pLP725 500 - 560 780 - 2100 pLP800 630 - 780 820 - 880 s

Reflection short passSP1500 1650 - 1700 1200 - 1380 p

• 1mm fused silica plate with wavelength dependent dielectric coating and 0.3° wedge angle for interference suppression

• Long pass (LP) and short pass (SP) version• Optimized for angle of incidence 45°, p-polarization• Fused silica plate • AR Coated reverse surface• Clear aperture 10 mm • Reflection up to 99 %, transmission up to 95 %

For a complete, fiber-coupled RGBV-Beam Combiner, see page 92.

Application:

For increasing the ex tinction ratio after collimating the radiation of a polarization-main taining fiber

Beam splitter and beam combiner with wedge-shaped substrate:

Substrate without wedge: Substrate with wedge: Mu

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Beam Combiners 48BC-CC-LP

Application: For the coincident coupling of laser diode beam sources of different wave lengths and identical polarization into one single-mode fiber

Two laser beams of different wavelengths are coaxially combined into a single laser beam with equal polarization. In adjustable mount, for mounting with clamp collar (included).

• Adjustable within adapter flange• Polarization: linear • Extinction ratio 10 000 : 1• Clear aperture 3.5 mm• Broadband AR coating: R < 0.5 % per surface• Variety of designs

Polarizers 48PM

Spectral rangeA = 450 – 700 nmB = 750 – 1100 nmC = 1100 – 1700 nmW= 450 – 1000 nm

48PM - S - AOrder Code

Order Options for Polarizer 48PM

Option S (standard) A S-D (decentered) B SXY1 (xy adjustment) AT-19.5AC (with attenuator) C

Polarizerin adapter flange as 48MB-19.5AC

Order Code

48MC-LI-19.5

Polarizer as 48PM-S decentered 0.3 mm for combining with beam splitter plate 48BS

Order Code

48PM-S-D

Polarizer with attenuator in adapter flange 48AT-19.5AC-S1

Order Code

48PM-AT-19.5AC

Beams are reflected twice at the media/air interfaces. The reflected beam is finally parallel with the unreflected beam. Both beams inter-fere, which causes intensity instabilites (Etalon effect). If they are coupled into a fiber, they are both focused onto the same spot and are both coupled.The intensity is not stable due to the interference of the beams.

The original beam and the twice reflected beam are not parallel but inclined after passing the substrate with wedge. After focusing that results in two distinct laser spots. Only the unreflected beam overlaps with the mode field of the fiber and the reflected radiation is lost. The removal of inter ference prevents intensity instabilities.

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The half-wave plate rotates the polarization direction of a linearly polarized input beam.

• clear aperture 5 mm

• in adjustable mount with self-locking tubular axis (0 - 360°)

• rotation around axis that is inclined 2° with respect to the optical axis. This avoids interference and back-reflection

• quartz platetype L: low order for low angle sensitivitytype Z: zero order for low wavelength dependency

The dichroic retardation plate is a /2-plate for one wavelength and does not affect the polarization of another wavelength. The correctly positioned plate rotates two ortho gonally polarized input beams of different wave lengths into linear polarization states in parallel.

Retardation Optics /2 48WP-2-CA

Dichroic Retardation Optics 48WP-2- -1-

Photo Detectors / Si-Detector 48PD-BPX61

Application: In combination with polarization beam splitter 48PM-CC, beam splitter with adjus table splitting ratio

Application:

In combination with polari zation beam splitter 48PM-CC, beam combiner for two wavelengths too close for dichroic beam combiners ( < 30 nm)

Application:

Power monitoring in combination with beam splitter 98/2 48BS-CC-PA

• clear aperture 5 mm

• in adjustable mount with self-locking tubular axis (0 - 360°)

• to avoid interference and back-reflection, the mount is inclined at 2° with respect to the tubular axis

• quartz plate of low order

• photodiode BPX 61

• spectral range 400 – 1100 nm

• > 50 nA/lx, > 320 mV/lx, 72 pF, 20 ns

• active area 7 mm2

• 3°-angled mount in housing for system mount Ø 19.5 mm

• diode and SMA connector galvanically isolated

248WP - 2 - CA - 780 LOrder Code

Order Options for Retardation Optics /2

low order Lzero order Z wavelength in nm

48WP - 2 - 780 - 1 - 767Order Code

Order Options for Dichroic Retardation Optics

wavelength in nm/2 wavelength in nm

48PD-BPX61Order Code

Order Options for Photo Detectors

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Schäfter+Kirchhoff offers numerous adapters and flanges suitable for incorporation into the multicube™ system. All standard adapters and flanges have Ø 19.5 mm system mount with a 19.5 mm tightly fitting cylinder. Some can be mounted using flange mounting.

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Accessories: Flanges and Adapters for System Mount Ø 19.5 mm

Adapter Flange with AttenuatorClear aperture: Ø 3 mm; Ø 19.5 mm system mount

Adapter for Ø 25 mm or Ø 25.4 mm mounted Optics

Tube with Ø 19.5 mm both ends

Order Code

48AT-19.5-S1

Order Code

19.5AF25.4-S

Order Code

48T-19.5

Representative selection. For more please contact Schäfter+Kirchhoff.

Adapter Flange for com ponents with Ø 8 mm for fitting to Ø 19.5 mm system mount

Order Code

48MB-19.5 A

Adapter Flange for components with Ø 8 mm to Ø 19.5 mm, decentered 0.3 mm

Order Code

48MB-19.5AC-D

thAdfor

Ø19

.5

Ø20

.5

0.3Ø

19.5

Ø25

Ø11

8 25.420.5

2.4

12.5Ø

25

Ø19

.5

Ø12

.5

Ø2.4

Ø19

.5

Ø12

.5 H

9

620.5

25.4

5.5

M27

x0.7

5

Ø25

.5

Ø15

Ø19

.5

Ø35

17.9

1.5

22.5

165.5

Ø19

.5

Ø19

.5

Ø25

M17

x0.7

5

20.5

1712

.7

25.4

Ø19

.5

Ø19

.5

5.8

2115

CapFor Ø 19.5 mm system mounting

Order Code

48C-19.5

Ø22

Ø19

.5

Ø23

7

5.5

Adapter for attaching Optics with Ø 8 mm toØ 19.5 mm for attaching e.g. 5M or 5PF

Adapter for Micros cope LensesAdapter for Ø 19.5 mm to W0.8"x1/36" male

Order Code

W0.8-19.5

Adapter for Microscope Lenses Ø 19.5 mm to W0.8"x1/36" female

Order Code

W0.8-I-19.5

for

M20

.25x

0.70

55

[0.8

0"]/

36G

Ø15

Ø19

.5

10.5

4

M20

.25x

0.70

55

[0.8

0"]/

36G

13.5

5.5

6

Ø15

Ø19

.5

Order Code

8AM-19.5

Ø23 Ø8

Ø19

.5

9.55.5

Light Trapfor absorbing unused beams

Order Code

48LT-19.5

25

23,5

Ø25

Ø22 Ø6

Ø19

,5

IrisAperture Ø 1 - 13 mm

IrisAperture Ø 0 - 12 mm

Order Code

13BL1-13

re

11.5

6

Ø25

Ø19

.5

Order Code

13BL0-12

Spacer with Ø 19.5 mm both ends

Order Code

48S-19.5

11

5.5

Ø19

.5

Ø19

.5Ø

22

Adapter Both ends with Ø 19.5 mm, male/female

Order Code

AC19.5/19.5-S

Ø25

Ø19

.5

Ø19

.5

13

6

5.5

Shutter Clear Aperture 5 mm, both ends with Ø 19.5 mm male/female,

Order Code

13S-5-1

Adapter C-mountAdapter for Ø 25 mm to C-mount

Order Code

C-mount-25

11

5

C-M

ount

[1"-

32G

ang]

Ø19

.5

Ø25

18 5.5

Ø25

h8

Ø19

.5

Ø19

.5 h

8

6

Adapter C-mountAdapter for Ø 19.5 mm to C-mount

Order Code

C-mount-19.5AC

C-M

ount

[1"-

32G

ang]

Ø14

Ø19

,5

11.5

5

er

Adapter for adapting Ø 12 mm components for Ø 19.5 mm mounting

Adapter for adaptingØ 25 mm components for Ø 19.5 mm mounting

Adapter Both ends with Ø 19.5 mm mount and v-groove

er for adapting

Order Code

12AM19.5

Order Code

19.5AC-25

Order Code

19.5AC19.5

Ø25

Ø12

Ø19

,5

14

Ø25

Ø20

Ø15

.5

Ø19

.5

12

5.5

Ø19

.5

Ø19

.5

Ø14

12

5.5

er

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Accessories and Tools for Assembly and Adjustment

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Accessories

Hex screw DIN 912 M2 x 8 for mounting Ø 19.5 mm componentsusing a clamp collar - set of 20/50 pcs.

Order Code

48-M2-8-912-20 48-M2-8-912-50

Hex Screwdriver Order Code

50HD-15

Grub screw DIN 551 M1.6 x 1.5 for fixing fiber ferrules to 60FC-... and 60SMS - set of 20/50 pcs.

Order Code

48-M1.6-1.5-551-2048-M1.6-1.5-551-50

Screwdriver Order Code

9D-12

Grub screw DIN 553 M1.6 x 1.5-conical for mounting Ø 8 mm com-ponents with v-groove - set of 20/50 pcs.

Order Code

48-M1.6-1.5-553-2048-M1.6-1.5-553-50

Screwdriver Order Code

9D-12

Rod for combining multicubes™

Order Code

48MC-6-L

L = 30L = 75L = 150xxx = length of choice

Hex grub screw DIN 914 M3x3-conical for mounting Ø 19.5 mm components with v-groove - set of 20/50 pcs.

Order Code

48-M3-3-914-2048-M3-3-914-50

Hex Screwdriver Order Code

50HD-15

Hex grub screw DIN 913 M3x3-flat for fixing rods to multicubes™ - set of 20/50 pcs.

Order Code

48-M3-3-913-2048-M3-3-913-50

Hex ScrewdriverOrder Code

50HD-15

LL

Tools for Assembly and Adjustment

Eccentric tool for laser beam couplers 60SMS and fiber collimators 60FC

Order Code

60EX-4

60EX-5 for focal length f’ 20 mm

Screwdriver WS 1.2 mm for grub screw in fiber ferrules and accessories 5M

Order Code

9D-12

Eccentric tool for fiber collimators 60FC-T and 60FC-Q...

Order Code

55EX-5

Hex screwdriver WS 1.5 mm for screwsDIN 912, 913, and 914

Order Code

50HD-15

Adjustment tool for rotating quarter-waveplates in fiber collimators 60FC-Q...

Order Code

60Z-2803

Eccentric tool with longer handle for laser beam couplers 60SMS-... and fiber collimators 60FC-... as an alternative to 60EX-4, 60EX-5, 55EX-5 above

Order Code

60EX-4-L

60EX-5-L 55EX-5-L

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Single-Cubewith through-holes for linear arrangements, short design

Mounting Platefor mounting Ø 19.5 or 25 mm system components

Extended Mounting Plate for mounting Ø 19.5 or 25 mm system components

Order Code

48MC-SM-19.5-Ti

Order Code

48MC-MP-19.5-Ti48MC-MP-25-Ti

Single-T-Cubefor T-arrangements

Order Code

48MC-LTS-19.5-Ti

Order Code

48MC-SP-19.5-Ti48MC-SP-25-Ti

Dimensions

Dimensions

Double-T-Cubefor T-arrangements

Order Code

48MC-LT-19.5-Ti

Order Code

48MC-LTD-19.5-Ti

Order Code

48MC-CL-19.5-Ti

Single-X-Cubefor X-arrangements

Triple-X-Cubefor X-arrangements

Titanium Combination Cubes and Plates 48MC-…-TiAmagnetic versions of the standard multicube™ components

Besides 60SMS laser beam couplers and 60FC fiber collimators some standard multicube components are availabe made of titanium.

The main advantage of these is a coefficient of thermal expansion CTE of titanium more close to that of glass compared the CTE of aluminum.

This provides even more stable multicube systems that can be used in hard environments.

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Titanium Optics Mounts for the multicube™ System

50:50 split ratio for linearly polarized input radiation with polarization direction = 45°. Maximum transmission at = 0° ( p-pol.) with maximum reflection at = 90° (s-pol.).• extinction ratio 10,000 : 1• clear aperture 6 mm • reflection angle 90°• broadband AR coating R < 0.5% per surface

Polarization Beam Splitters 48PM-CC...-Ti

Beam Splitter Cubes 50/50 48BM-CC...-Ti

Spectral range [nm]A = 450 - 700 nmB = 750 - 1100 nmC = 1100 - 1700 nm

48BM - CC - A - TiOrder Code

• 50:50 split ratio• independent of polarization• aperture 6 mm• reflection angle 90°• broadband AR coating per surface

Amagnetic version of Standard Beam Splitter and Beam Combiner, Polarizer, Retardation Optics

Beam-splitting cube with internal dielectric and polarizing multilayer coating. In adjustable mount, for mounting with clamp collar (included).

Order Options for Beam Splitter Cube 50/50 48BM-CC

Spectral range [nm]A = 450 - 700 nmB = 750 - 1100 nmC = 1100 - 1700 nmW= 450 - 1000 nm

48PM - CC - A - TiOrder Code

Order Options for Polarization Beam Splitter

Beam splitter with adjus table splitting ratio, in combination with retardation optics 48WP-CA

Application

Beam Splitter Cube 50/50 48BM-CC...-Ti

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Reflection long pass Transmission Pol.

LP436 370 - 412 460 - 700 sLP510 405 - 488 532 - 660 sLP570 532 - 544 594 - 660 sLP580 500 - 560 600 - 700 pLP725 500 - 560 780 - 2100 pLP800 630 - 780 820 - 880 s

Reflection short pass Transmission Pol.

SP1500 1650 - 1700 1200 - 1380 p

Beam Combiners 48BC-CC-LP...-Ti

Two laser beams of different wavelengths are coaxially combined into a single laser beam with equal polarization.

• 1mm fused silica plate with wavelength dependent dielectric coating and 0.3° wedge angle for interference suppression

• long pass (LP) and short pass (SP) version• optimized for angle of incidence 45°, p-polarization• fused silica plate • coated reverse surface• clear aperture 10 mm • reflection up to 99%, transmission up to 95%

Edge wavelength [nm]

48BC - CC - LP xxx - TiOrder Code

Order Options for Beam Combiners 48BC-CC-LP



Beam Splitters 98/2 48BS-CC-A-Ti

Beam Splitters 99/1 (10/90) 48BS-CC-B-Ti

48BS - CC - A - TiOrder Code

Order Options for Beam Splitters 98/2

48BS - CC - B - TiOrder Code

Order Options for Beam Splitters 99/1 (10/90)

• 1 mm fused silica plate, uncoated• 0.3° wedge angle for interference suppression• transmission 98% (p-polarization)• reflection 1% per surface (p-polarization)• clear aperture 10 mm

• 1 mm fused silica plate, back side coated (AR 400-700 nm)

• 0.3° wedge angle for interference suppression• reflection 1%, transmission 99% ( p-polarization)• reflection 10%, transmission 90% (s-polarization)• clear aperture 10 mm


Separation of a partial beam for power monitoring

Application:

For the coincident coupling of laser diode beam sources of different wave lengths and identical polarization into one single-mode fiber

Application

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Far

aday

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Faraday Isolators are used to protect laser sources from back-reflection (optical diode), which causes mode hopping, laser noise, frequency instability and a shorter laser lifetime.

Main features:

• High isolation >30 dB• Low insertion loss <0.5 dB • Aperture up to Ø 5 mm• Compatibility with multicubeTM and microbench /

cage systems• Through-holes for mounting rods• Standard wavelengths in a range of 400 to 1080 nm• Bandwidth: center wavelength ±20 nm

Faraday Isolators 48FIto protect laser sources from back-reflection

Dimensions Dimension [mm] Aperture [mm] Center Wave-length [nm] Order Coderow A B C D 2 3 5

1 80 70 48 19.5 x 400 48FI-5-400

2 39 27 20 18 x 532 48FI-2-532

3 65 55 33 19.5 x 532 48FI-5-532

4 39 27 20 18 x 633 48FI-2-633

5 65 55 33 19.5 x 633 48FI-5-633

6 91 70 32 19.5 x 660 48FI-5-660

7 80 70 48 19.5 x 670 48FI-5-670

8 65 55 33 19.5 x 780 48FI-5-780

9 65 55 33 19.5 x 810 48FI-5-810

10 65 55 33 19.5 x 850 48FI-5-850

11 100 90 68 19.5 x 980 48FI-5-980

12 92 82 60 19.5 x 1064 48FI-3-1064

13 100 90 68 19.5 x 1080 48FI-5-1080

Working Principle Benefits of using a Faraday Isolator

1 Polarizing beam splitter eliminates the s-polarized portion (typically 1 %) of the laser (diode) radiation

2 Faraday crystal in a strong magnetic field rotates the input polarization plane 45°

3 Polarizing beam splitter exactly aligned with the output polarization plane, i.e. by 45° with respect to the input polarization

4 Reflective or scattering surfaces cause polarized or depolarized reflected signals

5 Polarizing beam splitter 3 eliminates the s-polarized portion of the reflected signal

6 Faraday rotator 2 rotates the polarization plane by a further 45° so that the polarization plane of the reflected signal is now rotated by 90° from the polari zation plane of the input beam

7 Polarizing beam splitter 1 blocks the reflected signal

A Faraday Islolator protects the laser diode from back-reflection. If light is back-reflected into the laser source, it causes mode hopping. A typical spectrum is shown for an undisturbed and a laser beam source disturbed by back-reflected light. The disturbed spectrum shows multiple excited modes that change stochastically over time. This mode hopping results in laser noise, frequency instability and ultimately causes the laser lifetime to be decreased significantly.

Please note that because of its working principle the polarization of the beam passed by the Faraday isolator is rotated by 45° degrees in comparision with the input polarization.

1

2

1 Spectrum of an undisturbed laser beam source 2 Disturbed spectrum because of back-reflections

(mode hopping)

4230

ABC

Ø36D

Ø 6

4

Isolation

7

6

5

Beam input

Beam output

Transmission

32

1

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Application: Fiber-coupled Faraday Isolators

5

1

Set-up

Pos. Description Order Code Explanation

1Laser beam coupler

60SMS-1-4-for out and for in-coupling,adjustable

2Faraday isolator

48FI-avoids back-coupling of laser radiation into the fiber

3Attenuator/Shutter

48AT-A/ 48AT-SOption: Attenuator or shutter mechanism

4 Console 48MB-19.5-60

5Mounting Plate

48MC-MP-19.5

The fiber-to-fiber couplers with Faraday isolator from Schäfter+Kirchhoff supresse back-reflection and also offer - as an option - attenuator and shutter functio nalities.

A fiber-to-fiber coupler with Faraday isolator is used to protect laser beam sources where the attached fiber connectors cannot be removed (e.g. a fiber pigtail) or when back-coupling to the fiber is a desirable and discriminating characteristic (e.g. in interferometry).

They are used in combination with polarization-maintaining fiber cables.

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48AT-F with monitor diode 48AT-MD with motorized drive

Laser Attenuators 48AT are used for reproducible and precise reduction of the power output by the laser. The collimated laser beam is constricted by a precision ball transported by a scaled micrometer screw. The sub sequent single-mode fiber coupling is used as a mode filter.This mechanically stable attenuation method allows the precise and reproducible setting of the laser power output over a wide range (typically 0.5 to > 60 dB). Unlike a power regulation by modulation of the laser current, the wave-length and polarization status of the laser beam are preserved.• Reproducible power attenuation and safety constraints

are only assured for singlemode fibers that have a Gaussian intensity profile

Laser Attenuators 48ATfor reduction of output power

The 48AT-MD motorized laser attenuators are identical with the manual 48AT-0 laser attenuators in all respects, except for the replacement of the manual micrometer screw by a motorized version.

The additional parameters for the motorization are:• Closed-loop DC motors• Min. incremental motion down to 0.05 μm• Max. velocity 2 mm/s• Limit switch control• Controllable via USB and RS-232 interface• Macro-programmable stand-alone functionality• Additional I/O ports• DLLs and LabVIEW driver • User software

1% partial beam separation for power monitoring

Photo diodeode

Order Code 48 AT - F

For order code details see 48AT-0

LaserOUT

LaserIN

LaserIN

Configurations

Order Code 48 AT-MD

For order code details see 48AT-0

• Fiber collimator and laser beam coupler with inclined or coaxial coupling axis for single-mode fibers with FC-APC or FC-PC connector

• Insertion loss typically 0.5 dB, extinction > 60 dB• Can be used as interface between different types of fiber or connector

Input: Laser Beam Coupler 60SMS

Receptacle forFC-PC connector = 0FC-APC connector = 4(inclined coupling axis)

Assortment of Laser Beam Couplers 60SMS, see page 17

48 AT-0-SMS-1- 4 - A11 - 02 + SMS- 1- 4 - A11 - 02 Order Code

Output: Laser beam coupler 60SMSCoupling lens

Connection for 0 = FC-PC connector4 = FC-APC connector(inclined coupling axis)

Collimating lens

Order options for Laser attenuator 48AT

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Typical calibration curves

RelativePower Output

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Micrometer Position (mm)

Attenuation in dB

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Main features:

• Bistable shutter • No power consumption in OFF position• Internal, external, automatic or manual trigger mode• USB 2.0 and RS232 interface

Electromagnetic Shutters EMS-3-30 + SK97120 System mount Ø 19.5 mm, compatible with multicube™ system

Electrical scheme

Dimensions

Please note:

This shutter is bistable and so does NOT conform with the laser safety rules IEC 60825-1.

Shutter head: Order Code EMS-3-30

Controller with power supply, driver and control software: Order Code SK97120

multicube™ with shock absorbers:

Order Code 48MC-SM-19.5-SM

Order Options

Application: HeNe Lasers with Electromagnetic Shutter

Components1 HeNe laser 632.8 nm

2 Laser power supply

3 Mounting bracket MC-MG-C-44.5-F-R

4 Electrical shutter EMS-3-30

5 Shutter controller SK97120

6 Shutter power supply

7 multicube™ with shock absorbers 48MC-SM-19.5-SM

8 Attenuator 60A19.5-F-AT

9 Laser beam coupler 60SMS

10 Fiber cable SMC-630 / PMC-630

Upon activation, HeNe lasers require several minutes to reach a stable state of radia tion. To circumvent this latency, it is advantageous to use a shutter to block the beam, rather than subjecting the laser to a series of on-off cycles. In the present application, a shutter is mounted in a multicube™ immediately in front of the laser, with shock absorbers preventing any vibration caused by the shutter operation.

The power of the laser radiation can be reproducibly modulated with the attenuator 60A19.5-F-AT.

Subsequently, the beam is coupled using a highly efficient beam coupler into a single-mode SMC or a polarization- maintaining single-mode PMC fiber.

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Single laser pulses from a Mira Optima 900-P laser with Verdi V5 pump, emitting picosecond pulses at a repetition rate of 76 MHz, are selected by an acousto-optical pulse selector. Opto-mechanics and fiber optic components from Schäfter+Kirchhoff are used to couple the beam to a polarization-maintaining optical fiber cable.

Laser back-reflections are prevented by use of a Faraday isolator. The fiber coup ling is solidly mounted on an adjustable 4-axis translational and rotational stage.

Application: Single-Mode Fiber Coupling of a Picosecond Pulse Laser System

Fiber-Optical Solutions using the multicube™ system

Sensitive laser systems must be protected against back-reflections of the laser light. Schäfter+Kirchhoff can couple single-mode and polarization-maintaining fibers to a customer laser source and integrate a Faraday isolator to prevent laser feedback.

A complete system could have additional power monitors, as shown. To guarantee the highest coupling efficiencies, different kinds of beam- shaping optics can be used, e.g. beam expansion.

Application: Fiber Coupling with Beam Shaping and Feedback Protection

1064 nm

532 nm

ABCDE

Optical Scheme

A Innolight Prometheus B Beam expansion 48EOC Faraday isolator 48FID Laser beam coupler 60SMSE Polarization-maintaining single-mode

fiber cable PMC

A Mira Optima 900-P picosecond laserB Acousto-optical pulse picker C Faraday Isolator 48FI-5-830 D Laser beam coupler 60SMSE Polarization-maintaining single-mode fiber cable PMCF /2 Plate 48WP

Optical Scheme

Pulse PickerMira Optima PS-Laser Source

VerdiPump Laser

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Fiber-Optical Solutions using the multicube™ system

Optically pumped laser system consisting of:A High Power Optically Pumped Semiconductor Laser

(OPSL) type COHERENT Genesis MX, 488 nm.B Fiber coupling from Schäfter+Kirchhoff.

- Optical power 650 mW ex fiber - Single-mode - Polarization extinction ratio 23 dB.

To guarantee the highest long-term stability, the fiber-coupling system is completely enclosed in a protective housing. A fiber cable feedthrough acts as additional strain relief for the fiber cable.

Application: Fiber coupling of a COHERENT Genesis MX-Series

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Single-mode, Polarization-maintaining

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RMR-LIDAR (Rayleigh-Mie-Raman Light Detection and Ranging) is used by the ALOMAR (Arctic LIDAR Observatory for Meso-Atmospheric Research) facility in Norway for measuring the temperature and wind velocity in high altitudes.

Laser radiation from two pulsed power lasers is directed into the atmosphere. The radiation scattered back by aerosols (due to Rayleigh, Mie or Raman scattering) is collected by two 1.8 m terrestrial telescopes.

A frequency-stabilized seed laser is used to meet the strin-gent experimental restrictions for pulse length and spectral stability. The power lasers are alternately seeded, pulse-by-pulse, using two EOMs. The demanding specifications of the seeding process require the power lasers to emit extremely short pulses (~12 ns) of high spectral stability at a repetitive rate of 30 Hz.

Application: Triggered Laser-Seeding for LIDARfor measuring the temperature and wind velocity in high altitudes.

©A

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© Leibnitz Institute for Atmospheric Physics,

Kühlungsborn, Germany

All are assembled using Schäfter+Kirchhoff components and polariz ation-maintaining opti cal fibers around our proprietary multicube™ system. This robust, adaptable and modular system is a major improvement on conven tional, but bulky, optical breadboards.

A 532 nm / 1064 nm seeding laser A , iodine reference cell B and the electro-optical mo dulator units C are connected by the fiber port cluster D , which combines and distributes the laser beams.

A B

D C

C

construction kit "multicube" 48mc- - sch¤fter + kirchhoff gmbh

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