Compact high-power/high-energy 2 μm and mid-infrared laser sources for OCM

The paper describes two laser prototypes devoted to the jamming or the damaging of heat-seeking missiles for use in field trials. The semi-ruggedized compact jamming prototype is based either on an OP-GaAs or a ZnGeP2 (ZGP) OPO directly pumped by a 2.09 mu m Q-switched Ho3+:YAG laser with up to 20 W of average power around 2.1 mu m and an M-2 of less than 1.1. For jamming in band II, up to 3.5 W of average power were obtained and repetition rates from 20 kHz to 100 kHz were achieved. For 3.5 W of averaged output power, the M-2 of the signal and idler beams were estimated to be less than 1.2. The destruction laser consists of a Ho3+:LLF MOPA laser system which is used to pump a ZGP OPO. The maximum pulse energy of the Ho3+:LLF MOPA was 82 mJ at a repetition rate of 100 Hz. The pump beam quality was measured to M(2)x = 1.01 and M(2)y = 1.03 at a wavelength of 2053 nm. The total 3-5 mu m energy obtained for destruction was 23.4 mJ, corresponding to an optical-to-optical conversion efficiency of 51 %. The M-2 values of the signal were M(2)x = 1.81 and M(2)y = 1.98. The M-2 values of the corresponding idler beam were M(2)x = 1.91 and M(2)y = 1.94, respectively. ISL is also currently working on new laser sources and non linear conversion setups for proposing new versions that should be more compact, more efficient and more integrable.