This IR-blocking filter must not be confused with heat-resisting protection filters for projectors or spotlights. Instead, it is intended for use as protection for IR-sensitive CCD sensors or in the light path of illumination devices with low thermal characteristics. IR filter can block all visible light under 720nm, 850nm and 950nm. It gradually begins to absorb infrared radiation; long wave red light is slightly weakened, so that this filter has a subtle green tint. But in CCD applications, this can be readily corrected electronically.