Patent ID: 9273849
Filing Date: 2016-03-01
CPC Classification: B64D,F21V,G02B

Claim Text:
1. An NVIS (Night Vision Imaging System) illumination apparatus used to illuminate a region monitored by a night vision instrument, said illumination apparatus comprising: an illumination device, the illumination device comprising at least one LED, the illumination device being formed to emit mixed light with light components in the visible range, and an optical filter device for filtering the mixed light emitted by the illumination device, wherein the optical filter device is optically coupled to the illumination device when the illumination apparatus is used to illuminate the region, wherein the optical filter device blocks light with a cutoff wavelength of more than 610 nm, wherein the illumination device comprises a white LED, a green LED and a red LED, which together produce the mixed light, wherein the optical filter device comprises an interference filter device, and wherein a transmission of the optical filter device in a visible wavelength range below the cutoff wavelength of 610 nm is more than 80% for the light of the illumination device in the visible wavelength range, and in a red wavelength range above 610 nm is less than 1% for the light of the illumination device in the red wavelength range, such that attenuation of the mixed light is minimized to protect the night vision instrument.