Abstract: A forward looking infrared (FLIR) energy imaging device has been found to include components which are required by the receiver portion of a long-wavelength rangefinder. For example, the FLIR collecting lens system which focuses energy from a scene onto a sensitive, cooled detector array duplicates the function which must be performed by the laser rangefinder receiver. Thus an integrated laser/FLIR rangefinder comprises a laser transmitter for illuminating a target, and an IR energy optic channel having a FLIR for receiving IR energy and producing a visible image representative thereof, said FLIR including an afocal lens system for collecting and focusing energy from the target and energy from the laser return having a wavelength compatible with the band pass of the IR optics and detector onto a cooled sensitive detector.