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AD131 Photodetector Module 190nm to 4.8μm article

AD131 Photodetector Module 190nm to 4.8μm

  • Combines SP photodiode detector, programmable charge integrator, and data conversion in a compact package.
  • Expandible with add-on modules for cooled sensor capability.
  • Null function for background noise subtraction.
  • Programmable gain ranges.
  • Windows® based data acquisition software included.
  • Easy to install and use on any SP Monochromator.
  • Internal data averaging.
Compact, Convenient, Affordable

The AD131 is a computer controlled data acquisition device for photodiode detectors, covering a wide wavelength range with Si, InGaAs, PbS, and PbSe photocells from the AD4x series. The unit contains an internal programmable charge integration amplifier, a 16-bit A/D converter, and a microprocessor with a USB2.0 interface. Signal processing functions take place internal to the AD131 to greatly reduce the noise level of the measured signal, including Correlated Double Sampling (CDS) and signal oversampling for digital filtering. Windows® based software allows for stand-alone operation or integrated control and data acquisition with any of the Digikröm line of monochromators.
Adding the AD131-TC Thermoelectric Controller module to the AD131 enables the use of AD4x series heads with cooling capability (designated by a "-C" on the model name). AD4x heads are easily exchanged on the same AD131 unit.


SP Part # Detector Type Size Range Temp Sensitivity Dark resistance or current
AD421 Si 5.8x5.8 190-1000 25°C 0.4 A/W at 720 nm 20 pA
AD427* PbS 3x3 1000-2900 25°C 5x104 V/W at 2200 nm 0.5 to 2.5 MΩ
AD429* PbSe 3x3 1500-4800 25°C 5x102 at 4 µm 0.3 to 1.5 MΩ
AD430 InGaAs 3 dia 800-1700 25°C 0.95 A/W at 1.55 µm 15 nA
AD431 Si/InGaAs 2.4x2.4 300-1700 25°C 0.45 A/W at 0.94 µm 30 pA
    1 dia   25°C 0.55 A/W at 1.55 µm 1 nA

The following require the AD131-TC Thermoelectric Controller module in addition to the AD131 Photodetector module

SP Part # Detector Type Size Range Temp Sensitivity Dark resistance or current
AD427-C* Cooled PbS 4x5 1000-2900 -10°C 8x104 V/W at 2.2µm 0.5 tp 10 MΩ
AD429-C* Cooled PbSe 3x3 1500-4800 -10°C 1x103 V/W at 4 µm 1.7 to 7 MΩ
AD430-C Cooled InGaAs 3 dia 800-1700 -10°C 0.95 A/W at 1.55 µm 1 nA
AD431-C Cooled Si/InGaAs 2.4x2.4 300-1700 25°C 0.45 (25°C) at 0.94 µm 30 pA
    1 dia   -10°C 0.55 at 1.55 µm 0.07 nA

*Requires 450 Hz chopped optical signal


Feature Value
Wavelength Range: Depends on Sensor type
A/D Resolution: 16 bit
A/D Conversion Rate: 500kSPS
Response Rate: USB 2.0
Time Constant: 10µS, 100µS, 1mS, 10mS (selectable)
Low Pass Filter: 1/3Hz, 1Hz, 10Hz, 100Hz (selectable)
Phase Shift: 0-180 degrees (selectable)
Amplification Gain: x1 to x10 (selectable)
Phase Lock Loop Voltage Input: 0-5V optical chopper reference signal
Trigger Input Voltage: 0-5Vdc TTL
Supply Voltage: 100-240 Vac
USB2.0 Transfer Rate: 480 Mbits/S
Software: Windows® control program for stand-alone use or integrated with SP Monochromators.

Spectral Products & CVI Laser