Technology for Polarization Measurement

Avalanche Photodiode Photodetector Module

Hinds Instruments offers an avalanche diode photodetector module that is optimized for use with the PEM and low light levels. It is less expensive, safer, more rugged and easier to use than a photomultiplier tube (PMT).

The gain is adjustable and the bandwidth is DC to 450 kHz, making it useful for circular dichroism experiments and other polarization measurements that involve small, fast (PEM frequency) signals.

Hinds designed the module using an avalanche photodiode that is sensitive to a minimum 5 microWatt (at maximum gain) signal and is usable from 200 – 1000 nm. While it is not sensitive enough for photon counting, it is well suited for most other applications that previously required a PMT. Unlike a PMT, it does not require the expense or large footprint of a high voltage power supply.

APD-100 Specifications and Output Characteristics

Spectral Range (nm) Peak Sensitivity Wavelength Photodiode Diameter
200 - 1000 620 nm 5 mm


Effective Active Area NEP at Response Peak Frequency Bandwidth (3dB)
19.6 mm2 1 pW/√Hz DC to 450 kHz


Output Voltage at Saturation Min Gain 1.34
Max Gain 8.5
Photoelectric Sensitivity, V/W Min Gain λ = 620nm 0.04 x 106
Max Gain λ = 620nm 2 x 106
Maximum Input Light Level, uW Min Gain λ = 620nm 250
Max Gain λ = 620nm 5
Minimum Detection Limit Max Gain λ = 620nm 2 nW r.m.s.

Contact us for more information about our fast, sensitive photodetectors.