A number of experimental high p.r.f. CO2 TEA lasers have been demonstrated in the past in laboratory or tripod-mounted tests, but have not been sufficiently compact or rugged for incorporation into rangefinders for military. aircraft. Suitable forward-looking positions in aircraft are so confined that only Nd:YAG based rangefinders have found application to date and these pose much too high an eye-hazard to be used for routine terrain-following.
William F Woods,
"Compact CO2 Laser Rangefinders For Terrain - Following Applications", Proc. SPIE 0806, Active Infrared Systems and Technology, (24 August 1987); doi: 10.1117/12.941407; https://doi.org/10.1117/12.941407