We Present the new class of infrared Photodetectors based on the lead-tin tellurides doped with group III impurities. The Persistent photoconductivity effect appearing in these materials provides the opportunity of internal signal integration resulting in the considerable increase in signalto- noise ratio. The integration characteristic time may be changed by means of the operating temperature or alloy composition variation. Even if the integration time is higher than the operation time required there exists an opportunity to quench quickly (∼10−5s) the Persistent photoconductivity. In some regime of quenching the effect of giant quantum efficiency stimulation has been observed. Both the bulk crystal and thin film technologies of the Photodetector Production are developed.