Back to results
US 4,904,049 AGranted
High-contrast fiber optic diffusion faceplate with radiused fibers
AssigneeHughes Aircraft Company
InventorRonald G. Hegg
Life of this patent
Estimating the term…
Abstract
A radiused fiber optic faceplate is disclosed, particularly suited for use in optical apparatus comprising a high gain diffusion screen or a direct view CRT. The respective optical axis of the fibers are each substantially oriented so that the refracted information-bearing light passed through each fiber is directed to the exit pupil and ambient light from outside the exit pupil is absorbed in the faceplate. The faceplate therefore substantially increases the contrast enhancement.
Claims3
An optical apparatus, comprising:
- a diffusion holographic optical element comprising means for diffracting a beam of light incident upon any particular point on said element from a predetermined direction toward an exit pupil;
- and
- a fiber optic faceplate comprising a substantially flat external surface facing said exit pupil and having light absorbing material and a plurality of optical fibers therein, said faceplate positioned with respect to said holographic optical element so that diffracted light passes therethrough, and wherein the optical fibers are each characterized by an optical axis, with the optical fibers oriented so that the diffracted light passed through each optical fiber is substantially directed to said exit pupil;
- wherein ambient light incident on said external flat surface from outside said exit pupil is substantially absorbed by said light absorbing material, thereby enhancing the contrast provided by said optical apparatus.
1 more element
Dependencies are inferred from the claim text.