Multisensor detectors can be of great use to surveillance systems, whether they use intensified CCD, CMOS, InGaAs/short-wave infrared or long-wave infrared. These may be stand-alone systems or may incorporate a laser rangefinder or illuminator.
Modern surveillance should be able to detect and identify a specific target. Detecting a target or threat and then measuring the range to it, or illuminating it, generally requires a good multi-wave-length surveillance system.
However, no matter good the system, battlefield conditions or the weather can defeat its ability to meet these requirements. Thermal systems are excellent at detection but often have difficulty with identification. As a result, many of today's systems use various forms of laser illumination, continuous wave, as well as gated, to identify or designate the target.