Many night vision devices incorporate a built-in infrared (IR) diode that emits invisible light or the illuminator can be mounted on to it as a separate component. IR light cannot be seen by the unaided eye; therefore, a night vision device is necessary to see this light. IR Illuminators provide supplemental infrared illumination of an appropriate wavelength, typically in a range of wavelengths (e.g. 730nm, 830nm, 920nm), and eliminate the variability of available ambient light, but also allow the observer to illuminate only specific areas of interest while eliminating shadows and enhancing image contrast.
Regardless of generation all image intensifiers require some light to function. In situations where ambient light is insufficient, infrared (IR) illuminators facilitate night operations by providing an independent source of light. Since IR illuminators operate in near infrared range of 700 to 900 nanometers (nm), they are invisible to the naked eye.
Last Update: 04.01.2020