Eye-safe near infra-red imaging illumination method and system

A method and system for eye-safe near infra-red (NIR) optical imaging illumination. An eye of an intended subject are imaged with visible light or NIR light at an unconditionally eye-safe illumination level and the maximum permissible eye-safe NIR illumination that can be applied to the eye is determined from the captured images. The eye of the intended subject can then be illuminated with at least one substantially maximal NIR light pulse having a pulse intensity and duration selected to provide the substantially maximum permissible eye-safe NIR illumination intensity at the eye. NIR light pulse illumination can be inhibited in response to detection of other subjects either within the vicinity of a volume extending between an NIR illuminator illuminating the eye and the intended subject. The likelihood that an intended subject has been recently illuminated can also be determined and statistical measures can be used to avoid re-illuminating subject unnecessarily.