Sony IMX991AABA is a diagonal 4.1mm (type 1/4) InGaAs image sensor with a square pixel array and 0.33M effective pixels.

It achieves high sensitivity, high resolution, low dark current and low power consumption in the visible spectrum and in the SWIR wavelengths (from 0.4µm to 1.7µm). 

It is also equipped with a built-in thermoelectric cooler.