This B&W 52mm Infrared Blocking (Slim) Glass 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.
B&W slim filters are for wide-angle lenses and are 3mm thick. They do not have a front thread.
It suppresses infrared radiation >780 nm
Because it gradually begins to absorb infrared radiation at 600 nm, 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