• Compact, Handheld, Analog Needle, Power Meter Console
• Digital Display Screen
• Long-Life Internal Li-Polymer Battery
• Console comes Calibrated with Certificate of Calibration
• 1 GB USB Memory Stick with Software including LabVIEW™ and LabWINDOWS™ /CVI Driver Set, and Operating Manual

Please note that sensors are not included with the PM100A console. For information about our compatible sensors, please see the sensor descriptions below. Thorlabs does offer a variety of Power Meter Kits with the PM100A Console bundled with several of our most popular sensors. Please visit our Power Meter Kits page for more details.

A recalibration service is available for the PM100A; contact Tech Support for details. Alternatively, if you have a corresponding sensor that needs recalibrating, you can include the PM100A with the sensor for recalibration at no additional cost. To order this service, scroll to the bottom of the page and select the appropriate Item # that corresponds to your sensor.

Click to Enlarge
S120C and CP44F Quick-Release Mount

• For General Purpose Optical Power Measurements
• Integrated Viewing Target for Easy Sensor Alignment
• Ø9.5 mm Sensor Aperture
• Sensor, Protective Cap, IR Target, and Thread Adapter Included
• Fiber Adapters Available Separately (See Table Below)
• See the Full Web Presentation for More Information

These Standard Photodiode Power Sensors are ideal for metering low power coherent and incoherent sources from the UV to the NIR. Each NIST-Traceable, calibrated sensor features an integrated viewing target for easy alignment, enhanced shielding against electromagnetic interference, an over-temperature-alert device, and a large Ø9.5 mm sensor aperture. The sensors are compatible with 30 mm cage systems, Ø1/2" posts, and SM1 (1.035"-40) lens tubes, and are ideal for free-space and fiber-coupled sources.

Thorlabs offers a recalibration service for these photodiode power sensors, which can be ordered below (see Item # CAL1 for Si sensors and Item # CAL2 for Ge sensors).

Item #a	S120VC	S120C	S121C	S122C
Sensor Image (Click the Image to Enlarge)
Aperture Size	Ø9.5 mm
Wavelength Range	200 - 1100 nm	400 - 1100 nm	400 - 1100 nm	700 - 1800 nm
Power Range	50 nW - 50 mW		500 nW - 500 mW	50 nW - 40 mW
Detector Type	Si Photodiode (UV Extended)	Si Photodiode		Ge Photodiode
Linearity	±0.5%
Resolutionb	1 nW		10 nW	2 nW
Measurement Uncertaintyc	±3% (440 - 980 nm) ±5% (280 - 439 nm) ±7% (200 - 279 nm, 981 - 1100 nm)	±3% (440 - 980 nm) ±5% (400 - 439 nm) ±7% (981 - 1100 nm)		±5%
Responsivityd (Click for Plot)	Raw Data	Raw Data	Raw Data	Raw Data
Coating/Diffuser	Reflective ND (OD1.5)e	Reflective ND (OD1)f	Reflective ND (OD2)g	Absorptive ND (Schott NG9)
Head Temperature Measurement	NTC Thermistor 4.7 kΩ
Housing Dimensions	Ø30.5 mm x 12.7 mm
Cable Length	1.5 m
Post Mountinge,f,g	Universal 8-32 / M4 Tap, Post Not Included
Aperture Thread	External SM1 (1.035"-40)
Compatible Fiber Adapters	S120-FC, S120-APC, S120-SMA, S120-ST, S120-LC, and S120-SC (Not Included)
Compatible Consoles	PM400, PM100D, PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, and PM100USB

• For complete specifications, please see the Specs tab here.
• Measured with PM100D console in low bandwidth setting.
• Beam diameter > 1 mm.
• All sensor responsivities are calibrated to a NIST-traceable source with measurements taken in 5 nm intervals.
• For the S120VC, these specifications are valid for devices with serial numbers 1203xxx or higher. Older versions had a reflective ND diffuser (OD1). Additionally, they came with an 8-32 tap and M4 adapter. For additional information, please contact technical support.
• For the S120C, these specifications are valid for devices with serial numbers 1203xxx or higher. Older versions had an absorptive ND diffuser (Schott NG3). Additionally, they came with an 8-32 tap and M4 adapter. For additional information, please contact technical support.
• For the S121C, these specifications are valid for devices with serial numbers 1203xxx or higher. Older versions had a absorptive ND diffuser (Schott NG9). Additionally, they came with an 8-32 tap and M4 adapter. For additional information, please contact technical support.

Click to Enlarge

View Imperial Product List

Item #	Qty	Description
Imperial Product List
S130C	1	Slim Photodiode Power Sensor, Si, 400 - 1100 nm, 500 pW - 5 mW, Up to 500 mW with Filter
CP02	2	SM1-Threaded 30 mm Cage Plate, 0.35" Thick, 2 Retaining Rings, 8-32 Tap
TR6	1	Ø1/2" Optical Post, SS, 8-32 Setscrew, 1/4"-20 Tap, L = 6"
ER6-P4	3	Cage Assembly Rod, 6" Long, Ø6 mm, 4 Pack
CM1-BS013	1	30 mm Cage Cube-Mounted Non-Polarizing Beamsplitter, 400 - 700 nm, 8-32 and M4 Adapters
Add To CartExportForward

View Metric Product List

Item #	Qty	Description
Metric Product List
S130C	1	Slim Photodiode Power Sensor, Si, 400 - 1100 nm, 500 pW - 5 mW, Up to 500 mW with Filter
CP02/M	2	SM1-Threaded 30 mm Cage Plate, 0.35" Thick, 2 Retaining Rings, M4 Tap
TR150/M	1	Ø12.7 mm Optical Post, SS, M4 Setscrew, M6 Tap, L = 150 mm
ER6-P4	3	Cage Assembly Rod, 6" Long, Ø6 mm, 4 Pack
CM1-BS013	1	30 mm Cage Cube-Mounted Non-Polarizing Beamsplitter, 400 - 700 nm, 8-32 and M4 Adapters
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S130C Sensor in a 30 mm Cage

Click for Details
SM1A29 SM1 Thread Adapter
Mounted on a S130C Sensor

Click for Details

View Product List

Item #	Qty	Description
Universal Product List
S130C	1	Slim Photodiode Power Sensor, Si, 400 - 1100 nm, 500 pW - 5 mW, Up to 500 mW with Filter
FB-51	1	Single-Axis FiberBench, L = 51 mm, 5 Positions
FBSM	1	FiberBench Mount for Slim Photodiode Sensors
HCA3-SM1	1	FiberBench Wall Plate, FiberPort Compatible, Internally SM1-Threaded
PAF-X-5-B	1	FiberPort, FC/PC & FC/APC, f=4.6 mm, 600 - 1050 nm, Ø1.00 mm Waist
FBR-LPVIS	1	Rotating Linear Polarizer Module, 500 - 720 nm, Ø2.5 mm CA
Add To CartExportForward

S130C Photodiode Sensor Mounted in FiberBench System Using FBSM Mount

• For Optical Power Measurements in Confined Spaces
• Very Slim Design: 5 mm Thin on Sensor Side
• Ø9.5 mm Sensor Aperture
• Slideable ND Filter Automatically Changes Sensor Power Range
• Optional SM1A29 Adapter with VIS/IR Target and External SM1 Threading (More Details)
• Optional FBSM Mount with VIS/IR Target for FiberBench Systems (More Details)
• See the Full Web Presentation for More Information

These Slim Photodiode Power Sensors are designed to take optical source power measurements in locations where space and accessibility are at a premium. The 5 mm thin sensor end can fit between closely spaced optics, cage systems, and other arrangements where standard power meters may not fit. The NIST-Traceable, calibrated sensors also feature a large Ø9.5 mm sensor aperture and slideable neutral density filter for dual power ranges in one compact device.

A separately available SM1A29 adapter can be attached by 2 setscrews to any S130 series power sensor to mount fiber adapters, light shields, filters or any other SM1-threaded (1.035"-40) mechanics or optics. The FBSM Mount allows our S130 series power sensors to be mounted vertically into FiberBench systems for stable mounting with a minimal footprint.

Thorlabs offers a recalibration service for these photodiode power sensors, which can be ordered below (see Item # CAL-S130 for Si sensors and Item # CAL-S132 for Ge sensors).

Item #a	S130VC	S130C	S132C
Sensor Image (Click the Image to Enlarge)
Aperture Size	Ø9.5 mm
Wavelength Range	200 - 1100 nm	400 - 1100 nm	700 - 1800 nmb
Power Range (with Filter)	500 pW - 0.5 mWc (Up to 50 mW)c	500 pW - 5 mW (Up to 500 mW)	5 nW - 5 mW (Up to 500 mW)
Detector Type	Si Photodiode (UV Extended)	Si Photodiode	Ge Photodiode
Linearity	±0.5%
Resolution	100 pWd		1 nWe
Measurement Uncertaintyf	±3% (440 - 980 nm) ±5% (280 - 439 nm) ±7% (200 - 279 nm, 981 - 1100 nm)	±3% (440 - 980 nm) ±5% (400 - 439 nm) ±7% (981 - 1100 nm)	±5%
Responsivityg (Click for Plot)	Raw Data	Raw Data	Raw Data
Coating/Diffuser	Reflective ND (OD1.5)c	Reflective ND (OD2)h	Absorptive ND (Schott NG9/KG3)b
Housing Dimensions	150 mm x 19 mm x 10 mm; 5 mm Thickness on Sensor Side
Cable Length	1.5 m
Post Mounting	8-32 and M4 Taps
Adapters (Not Included)	SM1A29: Add SM1 Thread and Viewing Target to Aperture Fiber Adapters Compatible with SM1A29 Adapter: S120-FC, S120-APC, S120-SMA, S120-ST, S120-LC, and S120-SC FBSM: Integrate Sensor into FiberBench Setups
Compatible Consoles	PM400, PM100D, PM100USB, PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, and PM100USB

• For complete specifications, please see the Specs tab here.
• For the S132C, these specifications are valid for devices with serial numbers 1203xxx or higher. Older versions had a reflective ND diffuser (OD1), which would decrease the wavelength range from 700 nm to 1800 nm to 1200 nm to 1800 nm. For additional information, please contact technical support.
• For the S130VC, these specifications are valid for devices with serial numbers 1203xxx or higher. Older versions had an optical power range of 5 nW to 5 mW (50 nW to 50 mW with filter) and a reflective ND diffuser (OD1). For additional information, please contact technical support.
• Measured with PM100D console in low bandwidth setting, without filter.
• Measured with PM100D console in low bandwidth setting at 1550 nm, without filter.
• Beam Diameter > 1 mm.
• All sensor responsivities are calibrated to a NIST-traceable source with measurements taken in 5 nm intervals.
• For the S130C, these specifications are valid for devices with serial numbers 1203xxx or higher. Older versions had an absorptive ND diffuser (Schott NG9). For additional information, please contact technical support.

Item #a	S170C
Sensor Image (Click Image to Enlarge)
Overall Dimensions	76.0 mm x 25.2 mm x 5.0 mm (2.99" x 0.99" x 0.20")
Active Detector Area	18 mm x 18 mm
Input Aperture	20 mm x 20 mm
Wavelength Range	350 - 1100 nm
Optical Power Working Range	10 nW - 150 mW
Detector Type	Silicon Photodiode
Linearity	±0.5%
Resolutionb	1 nW
Calibration Uncertaintyc	±3% (440 - 980 nm) ±5% (350 - 439 nm) ±7% (981 - 1100 nm)
Responsivityd (Click for Plot)	Raw Data
Neutral Density Filter	Reflective (OD 1.5)
Cable Length	1.5 m
Post Mounting	Universal 8-32 / M4 Tap, Post Not Included
Compatible Consoles	PM400, PM100D, PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, and PM100USB

• For complete specifications, please see the Specs tab here.
• Measured with PM100D console in low bandwidth setting.
• Beam diameter > 1 mm.
• All sensor responsivities are calibrated to a NIST-traceable source with measurements taken in 5 nm intervals.

• Wavelength Range: 350 nm to 1100 nm
• Sensitive to Optical Powers from 10 nW to 150 mW
• Designed to Measure Optical Power at the Sample Plane of a Microscope
• Silicon Photodiode with Large 18 mm x 18 mm Active Area
• Sensor Housing Dimensions: 76.0 mm x 25.2 x 5.0 mm
• Index Matching Gel Utilized in Design to Prevent Internal Reflections
• Information Stored in Connector
  • Sensor Data
  • NIST- and PTB-Traceable Calibration Data
• Post Mountable via 8-32 (M4) Tap

The S170C Microscope Slide Power Sensor Head is a silicon photodiode sensor designed to measure the power at the sample in microscopy setups. The silicon photodiode can detect wavelengths between 350 nm and 1100 nm at optical powers between 10 nW and 150 mW. The sensor head's 76.0 mm x 25.2 mm footprint matches that of a standard microscope slide and is compatible with most standard upright and inverted microscopes.

The photodiode has an 18 mm x 18 mm active area and is contained in a sealed housing behind a neutral density (ND) filter with OD 1.5. A 20 mm x 20 mm indentation around the surface of the ND filter is sized to accept standard microscope cover slips. An immersion medium (water, glycerol, oil) may be placed in this well directly over the ND filter, or a cover slip may be inserted first to simplify clean up. The gap between the photodiode and the neutral density filter has been filled with an index matching gel in order to prevent internal reflections from causing significant measurement errors when using high NA objectives with oil or water.

The bottom of the sensor housing features a laser-engraved grid to aid in aligning and focusing the beam. In standard microscopes, this grid can be used for beam alignment before flipping the sensor head to face the objective for power measurements. In inverted microscopes, turn on the transmitted illuminator to align the grid on the detector housing with the beam, thereby centering the sensor in front of the objective. Alternatively, the diffusive surface of the ND filter can be used as a focusing plane.

Sensor specifications and the NIST- and PTB-traceable calibration data are stored in non-volatile memory in the sensor connector and can be read out by the latest generation of Thorlabs power meters. We recommend yearly recalibration to ensure accuracy and performance. Calibration may be ordered using the CAL1 recalibration service available below. Please contact technical support for more information.

Thorlabs also offers a Microscope Slide Sensor Head with a thermal sensor; for complete specifications, the full presentation can be found here.

Item #a	S175C
Sensor Image (Click Image to Enlarge)
Active Detector Area	18 mm x 18 mm
Wavelength Range	0.3 - 10.6 µm
Power Range	100 µW - 2 W
Detector Type	Thermal Surface Absorber (Thermopile)
Linearity	±0.5%
Resolutionb	10 µW
Measurement Uncertaintyc	±3% @ 1064 nm; ±5% @ 300 nm - 10.6 µm
Response Time	3 s (<2 s from 0 to 90%)
Housing Dimensions	76 mm x 25.2 mm x 4.8 mm (2.99" x 0.99" x 0.19")
Cable Length	1.5 m
Housing Features	Integrated Glass Cover Engraved Laser Target on Back
Post Mounting	N/A
Cage Mounting	N/A
Aperture Thread	N/A
Compatible Consoles	PM400, PM100D, PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, PM102, PM102A, PM102U, and PM100USB

• For complete specifications, please see the Specs tab here.
• Measured with the legacy PM200 Touch Screen Console
• Beam Diameter: >1 mm

Click to Enlarge
Typical absorption curve for the S175C (glass and absorber). Note that this curve is representative, and the actual absorption across the spectrum will vary from unit to unit.

Click to Enlarge
The back of the S175C housing is engraved with the sensor specifications and a target for centering the beam on the sensor.

• Wavelength Range: 300 nm - 10.6 µm
• Sensitive to Optical Powers from 100 µW to 2 W
• Designed to Measure Optical Power in the Sample Plane of a Microscope
• Thermal Sensor with 18 mm x 18 mm Active Area
• 76.0 mm x 25.2 mm Footprint Matches Standard Microscope Slides
• Information Stored in Connector
  • Sensor Data
  • NIST- and PTB-Traceable Calibration Data
• See the Full Web Presentation for More Information

The S175C Microscope Slide Thermal Power Sensor Head is designed to measure the power at the sample in microscopy setups. The thermal sensor can detect wavelengths between 300 nm and 10.6 µm at optical powers between 100 µW and 2 W. The sensor head's 76.0 mm x 25.2 mm footprint matches that of a standard microscope slide and is compatible with most standard upright and inverted microscopes.

The thermal sensor has an 18 mm x 18 mm active area and is contained in a sealed housing behind a glass cover. An immersion medium (water, glycerol, oil) may be placed over the glass cover plate.

As seen in the image to the right, the bottom of the sensor housing features a laser-engraved target to aid in aligning and focusing the beam. In standard microscopes, the target can be used for beam alignment before flipping the sensor head to face the objective for power measurements. In inverted microscopes, turn on the trans-illumination lamp and align the target on the detector housing with the beam; this will center the sensor in front of the objective.

Sensor specifications and the NIST- and PTB-traceable calibration data are stored in non-volatile memory in the sensor connector and can be read out by the latest generation of Thorlabs power meters. We recommend yearly recalibration to ensure accuracy and performance. Calibration may be ordered using the CAL-S200 recalibration service available below. Please contact technical support for more information.

Thorlabs also offers a Microscope Slide Sensor Head with a photodiode sensor for low-power, high-resolution measurements; the full presentation may be found here.

Click to Enlarge
S142C and S140-BFA Bare Fiber Adapter (Sold Separately)

Click to Enlarge
S142C with the S120-FC Fiber Adapter (Included)

• For Measurements Independent of Beam Shape and Entrance Angle
• Integrating Sphere Design Acts as a Diffuser with Minimal Power Loss
• Ø5 mm, Ø7 mm, or Ø12 mm Input Aperture
• Removable S120-FC Fiber Adapter (FC/PC and FC/APC) Included
• Compatible Fiber Adapters for Terminated and Bare Fiber (See Table Below)
• See the Full Web Presentation for More Information

These Integrating Sphere Photodiode Power Sensors are the ideal choice for power measurements independent of beam uniformity, divergence angle, beam shape, or entrance angle, making them excellent for use with fiber sources and off-axis free space sources.

Our integrating spheres are designed for wavelength ranges from the visible through the NIR. Sensor heads for use between 350 and 2500 nm use a single Ø1" or Ø2" sphere made from Zenith^® PTFE and feature a black housing to minimize reflected light around the entrance aperture. These sensors use either a silicon photodiode for detection in the 350 - 1100 nm range or an InGaAs photodiode for detection in the 800 - 1700 nm, 900 - 1650 nm, or 1200 - 2500 nm wavelength range.

The S180C integrating sphere for 2.9 - 5.5 µm uses two connected, gold-plated Ø20 mm spheres, with an entrance port in the first sphere and a port for the MCT (HgCdTe) detector located in the second sphere. Compared to single-sphere designs, the two-sphere configuration improves device sensitivity by minimizing the internal sphere surface area while still effectively shielding the detector from direct illumination. This design reduces the effect of input angle, divergence, and beam shape on the measurement result by effectively shielding the photodiode without the use of a baffle or other shielding mechanism.

The integrating spheres below feature large Ø5 mm, Ø7 mm, or Ø12 mm apertures, externally SM1-threaded (1.035"-40) front connections, enhanced shielding against electromagnetic interference, and an over-temperature alert sensor. Because of the large active detector areas of these sensors, the included S120-FC fiber adapter can be used with FC/PC- or FC/APC-terminated fiber. The externally SM1-threaded adapter can be removed using a size 1 screwdriver to place components closer to the window. NIST-traceable data is stored in the sensor connector.

Thorlabs offers a recalibration service for these photodiode power sensors, which can be ordered below. See Item # CAL1 for the S140C and S142C Si sensors; Item # CAL2 for the S144C, S145C, and S146C InGaAs sensors; and Item # CAL4 for the S148C InGaAs sensor or S180C MCT sensor.

Item #a	S140C	S142C	S144C	S145C	S146C	S148C	S180C
Sensor Image (Click the Image to Enlarge)
Aperture	Ø5 mm	Ø12 mm	Ø5 mm	Ø12 mm		Ø5 mm	Ø7 mm
Wavelength Range	350 - 1100 nm		800 - 1700 nm		900 - 1650 nm	1200 - 2500 nm	2.9 µm - 5.5 µm
Power Range	1 µW - 500 mW	1 µW - 5 W	1 µW - 500 mW	1 µW - 3 W	10 µW - 20 W	1 µW - 1 W	1 µW - 3 W
Detector Type	Si Photodiode		InGaAs Photodiode				MCT (HgCdTe) Photodiode
Linearity	±0.5%
Resolutionb	1 nW				10 nW	1 nW	10 nW
Measurement Uncertaintyc	±3% (440 - 980 nm) ±5% (350 - 439 nm) ±7% (981 - 1100 nm)		±5%
Responsivityd (Click for Plot)	Raw Data	Raw Data	Raw Data	Raw Data	Raw Data	Raw Data	Raw Data
Integrating Sphere Material (Size)	Zenith® PTFE (Ø1")	Zenith® PTFE (Ø2")	Zenith® PTFE (Ø1")	Zenith® PTFE (Ø2")		Zenith® PTFE (Ø1")	Gold Plating (Two Ø20 mm Spheres)
Head Temperature Measurement	NTC Thermistor 4.7 kΩ
Housing Dimensions	Ø45 mm x 30.5 mm	70 mm x 74 mm x 70 mm	Ø45 mm x 30.5 mm	70 mm x 74 mm x 70 mm		Ø45 mm x 30.5 mm	59.0 mm x 50.0 mm x 28.5 mm
Cable Length	1.5 m
Post Mounting	8-32 and M4 Taps
Aperture Thread	Included Adapter with SM1 (1.035"-40) External Thread
Compatible Fiber Adapters	S120-FC (Included) S120-APC, S120-SMA, S120-ST, S120-SC, S120-LC, and S140-BFA Bare Fiber Adapter (Not Included)
Compatible Consoles	PM400, PM100D, PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, and PM100USB

• For complete specifications, please see the Specs tab here.
• Measured with PM100D console in low bandwidth setting.
• Beam diameter > 1 mm
• All sensor responsivities are calibrated to a NIST-traceable source with measurements taken in 5 nm intervals except for the S180C. See the S180C responsivity graph to see the NIST-traceable reference points.

Click to Enlarge
PM100D with S150C Sensor and FC Cable

• For Fiber-Based Optical Power Measurements
• Compact Sensor Integrated into the Connector
• Integrated Design for use in the Field and Lab
• Includes PM20-FC Fiber Adapter
  • S150C and S151C Sensors also Include PM20-SMA Adapters
  • Compatible FC/APC, LC/PC, SC/PC, and ST Fiber Adapters Also Available (See Table Below)
• See the Full Web Presentation for More Information

The S15xC Compact Fiber Photodiode Power Sensor is designed to take power measurements from a wide variety of fiber coupled sources. The compact sensor, integrated into the power meter connector, features a unique integrated design housing the photodiode sensor, fiber coupling, and NIST-traceable data. Standard FC (and SMA - S150C and S151C) connectors are easily interchanged with a variety of standard fiber connectors.

Thorlabs offers a recalibration service for these photodiode power sensors, which can be ordered below (see Item # CAL1 for Si sensors and Item # CAL2 for InGaAs sensors).

Item #a	S150C	S151C	S154C	S155C
Sensor Image (Click the Image to Enlarge)
Included Connectors	FCb & SMA		FCb
Wavelength Range	350 - 1100 nm	400 - 1100 nm	800 - 1700 nm
Power Range	100 pW to 5 mW (-70 dBm to +7 dBm)	1 nW to 20 mW (-60 dBm to +13 dBm)	100 pW to 3 mW (-70 dBm to +5 dBm)	1 nW to 20 mW (-60 dBm to +13 dBm)
Detector Type	Si Photodiode		InGaAs Photodiode
Linearity	±0.5%
Resolutionc	10 pW (-80 dBm)	100 pW (-70 dBm)	10 pW (-80 dBm)	100 pW (-70 dBm)
Measurement Uncertaintyd	±3% (440 - 980 nm) ±5% (350 - 439 nm) ±7% (981 - 1100 nm)	±3% (440 - 980 nm) ±5% (400 - 439 nm) ±7% (981 - 1100 nm)	±5%
Responsivityf (Click for Details)	Raw Data	Raw Data	Raw Data	Raw Data
Coating/Diffuser	N/A	Absorptive ND (Schott NG3)	N/A
Head Temperature Measuremente	NTC Thermistor 3 kΩ
Aperture Thread	External SM05 (0.535"-40)
Fiber Adapters	Included: PM20-FC and PM20-SMA Optional: PM20-APC, PM20-LC, PM20-SC, and PM20-ST		Included: PM20-FC Optional: PM20-APC, PM20-LC, PM20-SC, PM20-ST, and PM20-SMA
Compatible Consoles	PM400, PM100D, PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, and PM100USB

• For complete specifications, please see the Specs tab here.
• Because of the large active detector area of these sensors, the included PM20-FC fiber adapter can be used with both FC/PC- and FC/APC-terminated fiber. 
• Measured with PM100D console in low bandwidth setting.
• For a beam diameter > 1 mm incident on the active area of the detector (i.e. at the detector surface after the light has exited the fiber and passed through any internal optics).
• This specification is valid for devices with serial numbers 1203xxx and higher. For older versions, please contact technical support.
• All sensor responsivities are calibrated to a NIST-traceable source with measurements taken in 5 nm intervals.

Item #a	S401C	S405C
Sensor Image (Click the Image to Enlarge)
Wavelength Range	190 nm - 20 µm	190 nm - 20 µm
Optical Power Range	10 µW - 1 W (3 Wb)	100 µW - 5 W
Input Aperture Size	Ø10 mm	Ø10 mm
Active Detector Area	10 mm x 10 mm	10 mm x 10 mm
Max Optical Power Density	500 W/cm² (Avg.)	1.5 kW/cm² (Avg.)
Detector Type	Thermal Surface Absorber (Thermopile) with Background Compensation	Thermal Surface Absorber (Thermopile)
Linearity	±0.5%	±0.5%
Resolutionc	1 µW	5 µW
Measurement Uncertaintyd	±3% @ 1064 nm ±5% @ 190 nm - 10.6 µm	±3% @ 1064 nm  ±5% @ 250 nm - 17 µm
Response Timee	1.1 s	1.1 s
Cooling	Convection (Passive)
Housing Dimensions (Without Adapter)	33.0 m x 43.0 mm x 15.0 mm (1.30" x 1.69" x 0.59")	40.6 mm x 40.6 mm x 16.0 mm (1.60" x 1.60" x 0.63")
Temperature Sensor (In Sensor Head)	NTC Thermistor	NTC Thermistor
Cable Length	1.5 m
Post Mounting	Universal 8-32 / M4 Taps (Post Not Included)	Universal 8-32 / M4 Taps (Post Not Included)
30 mm Cage Mounting	-	Two 4-40 Tapped Holes & Two Ø6 mm Through Holes
Aperture Threads	-	Internal SM05
Accessories	Externally SM1-Threaded Adapter Light Shield with Internal SM05 Threading	Externally SM1-Threaded Adapter
Compatible Consoles	PM400, PM100D, PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, PM102, PM102A, PM102U and PM100USB

• For complete specifications, please see the Specs tab here.
• For conditions of intermittent use, with a maximum exposure time of 20 minutes for the S401C. The S405C saturates for optical input powers >5 W.
• Measurement taken with the legacy PM200 console for the S401C and the PM400 console for the S405C. In all cases, the acceleration circuit was switched off. Resolution performance will be similar with our other power meter consoles.
• Defined as the measurement uncertainty during calibration at the specified wavelengths for a beam diameter > 1 mm. The ±3% specification was determined by laser calibration, and the ±5% specification was determined through spectral calibration, in which values were interpolated using the laser calibration data and the absorption curve for the absorber. Calibration can be performed at 10.6 µm upon request. 
• Typical natural response time (0 - 95%). Our power consoles can provide estimated measurements of optical power on an accelerated time scale (typically <1 s). See the Operation tab for additional information.

• High Resolution of 1 μW or 5 μW
• S401C and S405C Have Thermistors Used to Monitor Temperature of Sensor Head
• S401C: Background Compensation for Low-Drift Measurements
• S405C: Accommodates Average Optical Power Densities up to 1.5 kW/cm²
• See the Full Web Presentation for More Information

Click to Enlarge
S401C Thermal Sensor with Included Light Shield

Thorlabs offers two broadband thermal power sensors designed to measure low optical power sources with high resolution. Each thermal sensor's broadband coating has a flat spectral response over a wide wavelength range, as shown in the plot below.

An aperture size of Ø10 mm allows for easy alignment and measurement of large-spot-size laser sources. For easy integration with Thorlabs' lens tube systems and SM1-threaded (1.035"-40) fiber adapters, each sensor has either external SM1 threading or includes an externally SM1-threaded adapter.

The S401C uses active thermal background compensation to provide low-drift power measurements. This is implemented through the use of two similar sensor circuits. One sensor circuit is the type all thermal power sensors share: it measures heat flow from light absorber to heat sink. The other sensor circuit monitors the ambient temperature. It is located within the housing and measures heat flow from heat sink towards the absorber. The measurements of the two sensor circuits are subtracted, which minimizes the effect of thermal drift on the laser power measurement. (For information about how the external thermal disturbances can affect thermal power sensor readings, see the Operation tab.) The broadband coating used on this thermal sensor offers high absorption at wavelengths between 0.19 and 20 µm (shown in the graph), which makes the sensor ideal for use with aligning and measuring Mid-IR Quantum Cascade Lasers (QCLs). The included, internally SM05-threaded (0.535"-40) light shield is shown in the photo to the right.

The S405C has internal SM05 (0.535"-40) threading that is directly compatible with SM05 lens tubes, and it can also connect directly to Thorlabs' 30 mm Cage Systems.

Thorlabs offers a recalibration service for these sensors, which can be ordered below (see Item # CAL-S200).

Click to Enlarge
The S405 shares the same absorption curve with the S415C, S425C, and S245C-L. (All are sold below.)

Item #a	S415C	S425C
Sensor Image (Click Image to Enlarge)
Wavelength Range	190 nm - 20 µm	190 nm - 20 µm
Optical Power Range	2 mW - 10 W (20 Wb)	2 mW - 10 W (20 Wb)
Input Aperture Size	Ø15 mm	Ø25.4 mm
Active Detector Area	Ø15 mm	Ø27 mm
Max Optical Power Density	1.5 kW/cm² (Avg.)	1.5 kW/cm² (Avg.)
Detector Type	Thermal Surface Absorber (Thermopile)
Linearity	±0.5%	±0.5%
Resolutionc	100 µW	100 µW
Measurement Uncertaintyd	±3% @ 1064 nm ±5% @ 250 nm - 17 µm	±3% @ 1064 nm ±5% @ 250 nm - 17 µm
Response Timee	0.6 s	0.6 s
Cooling	Convection (Passive)
Housing Dimensions (Without Adapter)	50.8 mm x 50.8 mm x 35.0 mm (2.00" x 2.00" x 1.38")	50.8 mm x 50.8 mm x 35.0 mm (2.00" x 2.00" x 1.38")
Temperature Sensor (In Sensor Head)	NTC Thermistor
Cable Length	1.5 m
Post Mounting	Universal 8-32 / M4 Taps (Post Not Included)	Universal 8-32 / M4 Taps (Post Not Included)
30 mm Cage Mounting	-	-
Aperture Threads	Internal SM1	Internal SM1
Removable Heatsink	Yes	Yes
Accessories	Externally SM1-Threaded Adapter	Externally SM1-Threaded Adapter
Compatible Consoles	PM400, PM100D, PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, PM102, PM102A, PM102U and PM100USB

• For complete specifications, please see the Specs tab here.
• Two Minute Maximum Exposure Time
• Measurement taken with the PM400 with the acceleration circuit switched off. Resolution performance will be similar with our other power meter consoles.
• Defined as the measurement uncertainty during calibration at the specified wavelengths for a beam diameter > 1 mm. The ±3% specification was determined by laser calibration, and the ±5% specification was determined through spectral calibration, in which values were interpolated using the laser calibration data and the absorption curve for the absorber. Calibration can be performed at 10.6 µm upon request.
• Typical natural response time (0 - 95%). Our power consoles can provide estimated measurements of optical power on an accelerated time scale (typically <1 s). As the natural response times of the S415C and S425C are fast, these do not benefit from accelerated measurements and this function cannot be enabled. See the Operation tab for additional information.

• 100 µW Optical Power Resolution
• Thermistors Used to Monitor Temperature of Sensor Head
• Removable Heat Sinks Included
• See the Full Web Presentation for More Information

These thermal power sensors are designed for general broadband power measurements of low and medium power light sources. All include an externally SM1-threaded (1.035"-40) adapter, with threading concentric with the input aperture. The adapters are useful for mounting Ø1" Lens Tubes and Fiber Adapters (available below). The apertures of the S415C and S425C have internal SM1 threading.

These sensors operate with fast (<0.6 s) natural response times, and their removable heat sinks provide a high degree of flexibility to those interested in integrating them into custom setups or replacing the included heat sink with one that is water or fan cooled. If replacing the heat sink, please note that the replacement must provide heat dissipation adequate for the application.

Thorlabs offers a recalibration service for these sensors, which can be ordered below (see Item # CAL-S200).

Click to Enlarge
The absorption curves of each of the thermal power sensors designed for use with low and medium power optical sources.

Click to Enlarge
The absorption curves of each of the thermal power sensors designed for use with low and medium power optical sources.

• Thermistors Used to Monitor Temperature of Sensor Head
• S322C Has 4-40 Taps for Use with Our 30 mm Cage Systems
• S350C Has Ø40 mm Aperture Well Suited to Excimer and Other Lasers with Large Spot Sizes
• S425C-L Features Removable Heat Sink
• S322C is Fan Cooled with an Optical Power Range up to 200 W
• See the Full Web Presentation for More Information

These thermal power sensors are designed for general broadband power measurements of low and medium power light sources. With the exception of the S350C, all include an adapter with external SM1 (1.035"-40) threading concentric with the input aperture. This allows the sensors to be integrated into existing Ø1" lens tube systems in addition to being compatible with fiber adapters (available below). The aperture of the S425C-L has internal SM1 threading.

The S425C-L operates with a fast (<0.6 s) natural response time and has a removable heat sink, which provides a high degree of flexibility to those interested in integrating them into custom setups or replacing the included heat sink with one that is water or fan cooled. If replacing the heat sink, please note that the replacement must provide heat dissipation adequate for the application.

Thorlabs offers a recalibration service for these sensors, which can be ordered below (see Item # CAL-S200).

Item #a	S350C	S425C-L	S322C
Sensor Image (Click Image to Enlarge)
Wavelength Range	190 nm- 1.1 µm, 10.6 µm	190 nm - 20 µm	250 nm - 11 µm
Optical Power Range	10 mW - 40 W (60 Wb)	2 mW - 50 W (75 Wb)	100 mW - 200 W (250 Wb)
Input Aperture Size	Ø40 mm	Ø25.4 mm	Ø25 mm
Active Detector Area	Ø40 mm	Ø27 mm	Ø25 mm
Max Optical Power Density	2 kW/cm² (Avg.)	1.5 kW/cm² (Avg.)	4 kW/cm² (Avg., CO2)
Detector Type	Thermal Surface Absorber (Thermopile)
Linearity	±1%	±0.5%	±1%
Resolutionc	1 mW	100 µW	5 mW
Measurement Uncertaintyd	±3% @ 351 nm ±5% @ 190 nm - 1100 nm	±3% @ 1064 nm  ±5% @ 250 nm - 17 µm	±3% @ 1064 nm ±5% @ 266 nm - 1064 nm
Response Timee	9 s (1 s from 0 to 90%)	0.6 s	5 s (1 s from 0 to 90%)
Cooling	Convection (Passive)		Forced Air with Fanf
Housing Dimensions (Without Adapter, if Applicable)	100 mm x 100 mm x 54.2 mm (3.94" x 3.94" x 2.13")	100.0 mm x 100.0 mm x 58.0 mm (3.94" x 3.94" x 2.28")	100 mm x 100 mm x 86.7 mm (3.94" x 3.94" x 3.41")
Temperature Sensor (In Sensor Head)	NTC Thermistor
Cable Length	1.5 m
Post Mounting	M6 Threaded Taps, Includes Ø1/2" Post, 75 mm Long	Universal 8-32 / M4 Taps (Post Not Included)	M6 Threaded Taps, Includes Ø1/2" Post, 75 mm Long
30 mm Cage Mounting	-	-	Four 4-40 Tapped Holes
Aperture Threads	-	Internal SM1	-
Removable Heatsink	-	Yes	-
Accessories	-	Externally SM1-Threaded Adapter	Externally SM1-Threaded Adapter
Compatible Consoles	PM400, PM100D,  PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, PM102, PM102A, PM102U and PM100USB

• For complete specifications, please see the Specs tab here.
• Two Minute Maximum Exposure Time
• Measurement taken with the PM100D console, except for the S425C-L in which the PM400 was used. In all cases, the acceleration circuit was switched off. Resolution performance will be similar with our other power meter consoles.
• Defined as the measurement uncertainty during calibration at the specified wavelengths for a beam diameter > 1 mm. The ±3% specification was determined by laser calibration, and the ±5% specification was determined through spectral calibration, in which values were interpolated using the laser calibration data and the absorption curve for the absorber. Calibration can be performed at 10.6 µm upon request.
• Typical natural response time (0 - 95%). Our power consoles can provide estimated measurements of optical power on an accelerated time scale (typically <1 s) for the S350C and S322C. As the natural response time of the S425C-L is fast, the S425C-L does not benefit from acceleration and this function cannot be enabled. See the Operation tab for additional information.
• 12 VDC power supply is included.

Item #a	S370C	S470C
Sensor Image (Click the Image to Enlarge)
Wavelength Range	400 nm - 5.2 µm	250 nm - 10.6 µm
Optical Power Range	10 mW - 10 W (15 Wb)	100 µW - 5 W (Pulsed and CW)
Input Aperture Size	Ø25 mm	Ø15 mm
Active Detector Area	Ø25 mm	Ø16 mm
Max Optical Power Density	35 W/cm² (Avg.); 100 GW/cm² (Peak)
Detector Type	Thermal Volume Absorber (Thermopile)
Linearity	±1%	±0.5%
Resolutionc	250 µW	10 µW
Measurement Uncertaintyd	±3% @ 1064 nm  ±5% @ 400 nm - 1064 nm	±3% @ 1064 nm  ±5% @ 250 nm - 10.6 µm
Response Timee	45 s (3 s from 0 to 90%)	6.5 s (<2 s from 0 to 90%)
Cooling	Convection (Passive)
Housing Dimensions (Without Adapter, if Applicable)	75 mm x 75 mm x 51.2 mm (2.95" x 2.95" x 2.02")	45.0 mm x 45.0 mm x 18.0 mm (1.77" x 1.77" x 0.71")
Temperature Sensor (In Sensor Head)	N/A	N/A
Cable Length	1.5 m
Post Mounting	M6 Threaded Taps, Includes Ø1/2" Post, 75 mm Long	Universal 8-32 / M4 Tap (Post Not Included)
30 mm Cage Mounting	Four 4-40 Tapped Holes	-
Aperture Threads	-	External SM1
Accessories	Externally SM1-Threaded Adapter	-
Compatible Consoles	PM400, PM100D, PM100A, and PM320E
Compatible Interfaces	PM101, PM101A, PM101R, PM101U, PM102, PM102A, PM102U and PM100USB

• For complete specifications, please see the Specs tab here.
• Two Minute Maximum Exposure Time
• Measurement taken with the PM100D console for the S370C and with the legacy PM200 for the S470C. In all cases, the acceleration circuit was switched off. Resolution performance will be similar with our other power meter consoles.
• Defined as the measurement uncertainty during calibration at the specified wavelengths for a beam diameter > 1 mm. The ±3% specification was determined by laser calibration, and the ±5% specification was determined through spectral calibration, in which values were interpolated using the laser calibration data and the absorption curve for the absorber. Calibration can be performed at 10.6 µm upon request.
• Typical natural response time (0 - 95%). Our power consoles can provide estimated measurements of optical power on an accelerated time scale (typically <2 s). See the Operation tab for additional information.

• Designed for Optical Power Measurements of Nd:YAG Lasers
• Ideal for Applications with High Peak Pulse Powers
• S370C: Ø25 mm Aperture for Large-Spot-Size Beams
• S470C: High-Sensitivity for High-Peak-Power Pulses with Low Average Power
• See the Full Web Presentation for More Information

The S370C and S470C Thermal Sensors are designed to measure short and highly energetic laser pulses. All of these units are post-mountable for free-space applications and feature NIST-traceable data stored in the sensor connector.

These thermal power sensors are unique in that they have thermal volume absorbers, where our other thermal power sensors have thermal surface absorbers. The volume absorber consists of a Schott glass filter. Incident pulses are absorbed and the heat is distributed throughout the volume. In this way, pulses that would have damaged the absorption coating of a thermal surface absorber are safely measured by these thermal volume absorbers. 

The S370C features a large Ø25 mm aperture ideal for large-spot-size beams, and it is compatible with average powers from 10 mW to 10 W (CW).

In comparison, the S470C is faster, as the glass absorber volume is reduced and other design parameters have been optimized for speed. This results in a different optical power range, with the ability to measure powers down to 100 µW. The Ø15 mm aperture is of the S470C is smaller, and it has a lower max average power of 5 W. Its 10 µW resolution is better than the 250 µW resolution of the S370C.

Thorlabs offers a recalibration service for these sensors, which can be ordered below (see Item # CAL-S200).

Click to Enlarge
This absorption curve is shown over a broader wavelength range than the sensors' operating ranges. See the table for the operating wavelength range of each sensor.

Thorlabs offers calibration services for our photodiode optical power sensors and consoles. To ensure accurate measurements, we recommend recalibrating the sensors annually. Recalibration of the console is included with the recalibration of a sensor at no additional cost. If you wish to recalibrate only your power meter console, please contact Tech Support for details.

Refer to the table to the right for the appropriate calibration service Item # that corresponds to your power meter sensor. Once the appropriate Item # is selected, enter the Part # and Serial # of the sensor that requires recalibration prior to selecting Add to Cart.

Thorlabs offers recalibration services for our thermal power and pyroelectric energy sensors. To ensure accurate measurements, we recommend recalibrating the sensors annually. Recalibration of the console is included with the recalibration of a sensor at no additional cost. If you wish to recalibrate only your power meter console, please contact Tech Support for details.

The table to the right lists the sensors for which this calibration service is available. Please enter the Part # and Serial # of the sensor that requires recalibration prior to selecting Add to Cart.