Tuneable lasers for countermeasures - a literature survey

Directed infrared counterrneasures (DIRCM) against infrared sensing missile seekers generally require wavelength tuneable in band laser sources. When combining a laser with wavelength conversion devices such as optical parametric oscillators it is possible to cover a large part of the 2-5 µm wavelength transmission window in the atmosphere. Also the 8-12 µm band may be accessible with this or similar techniques. This is an initiative to resume the development of lasers for countermeasures especially for directed infrared countermeasures (DIRCM) applications at FOI. In this report a survey of the development of threats is given followed by some examples of ongoing developments of DIRCM systems. Some methods for frequency conversion are discussed and briefly explained. Various pump-sources are then shortly discussed. This is followed by a literature survey of different IR-OPO techniques with results from conversion to mid-IR wavelengths. Finally current and future needs are discussed and some suggestions for future work on this subject are given.