APD modules enable very low light levels to be detected quickly and simply in a variety of applications such as laser radar, range finding, data transfer or biomedical analysis.

The APD modules are based on low-noise avalanche photodiodes made of either silicon or InGaAs with a built-in pre-amplifier and high voltage supply. A temperature compensation function allows the APD to be operated at constant gain across a wide operating temperature range. Also the gain value is adjustable by remote software Control. Users can set the values depending on the intensity of the laser.