Visible light sensor mechanism for constant brightness projection systems

Abstract

An apparatus for collecting and sensing light in a projector, comprising a cold mirror positioned directly in the incident light path from a lamp and illumination optics of the projector for reflecting a large portion of visible light towards a light imaging device while transmitting IR and UV light and a small portion of the visible light; a secondary mirror for reflecting the small portion of the visible light, an integrating box positioned to collect and integrate the small portion of visible light, a light tube in optical communication with the integrating box for further integrating and attenuating the small portion of visible light, and an electro-optic device within the light tube for measuring the small portion of visible light within the light tube and generating an electrical signal in response thereto.

Dependencies are inferred from the claim text.