Results of scientific and reseach work in development of photodetective assembly consising of a photodetector, based on PbSe (8x8) area array and a thermoelectric cooler, and a processing and control device are given. Possibility of realizing a threshold flow of 6.32x10^-8 W/el at modulation frequency of 1200 Hz, signal transmitting band of 150 Hz, layer temperature of 22 degrees Celsius is shown.