04859031 is referenced by 107 patents and cites 6 patents.

An optical collimating apparatus employs a semi-reflective concave mirror and cholesteric liquid crystal element. In one embodiment, the optical collimating apparatus is used as a heads-up display device. Images in the line of sight of an observer substantially pass through a transmitter/combiner, semi-reflective concave mirror, and cholesteric liquid crystal element to an observer. Images generated by an image source are focussed on the transmitter/combiner such that the transmitter/combiner reflects the images into the line of sight of the observer. The generated images are transmitted by the primarily transmissive (convex) side of the semi-reflective concave mirror to the cholesteric liquid crystal element. The cholesteric liquid crystal element reflects the generated images back toward the primarily reflective (concave) side of the semi-refective concave mirror, which in turn reflects the images back toward the cholesteric liquid crystal element, which transmits the generated images to the observer. In an alternative embodiment, such as in a flight simulator or similar device, an image source projects images upon the primarily transmissive (convex) side of a semi-reflective concave mirror which transmits the images to a cholesteric liquid crystal element. The images are reflected by the cholesteric liquid crystal element back toward the primarily reflective (concave) side of the semi-reflective concave mirror. The images are then reflected by the semi-reflective concave mirror back toward the cholesteric liquid crystal element which transmits the images to the observer.

Title
Optical collimating apparatus
Application Number
7/80739
Publication Number
4859031
Application Date
August 3, 1987
Publication Date
August 22, 1989
Inventor
James E Melzer
San Jose
CA, US
Arthur L Berman
Milpitas
CA, US
Agent
Townsend and Townsend
Assignee
Kaiser Electronics
CA, US
IPC
G02F 1/13
G02B 5/30
G02B 27/14
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