3702930 is referenced by 4 patents and cites 11 patents.

A system for efficiently projecting the light from a point or line light source to a specified area in a remote object plane. Two separate families of concentrically disposed ellipses are positioned to share a common focus and to have the other focus of each ellipse family disposed on the remote object plane, so that the distance between the two focuses on the object plane defines the area on the plane to be illuminated. The light source is placed at the common focus of the two families of ellipses, and elliptical reflecting segments from the two families of ellipses are disposed about the light source to direct the light from the light source to the defined area on the object plane. Proper orientation of the elliptical reflecting segments allows for all of the light from the light source to pass to the designated area on the object plane in one or less reflections against the elliptical reflecting segments.

Title
Remote illuminating apparatus
Application Number
05/123,504
Publication Number
3702930
Application Date
March 12, 1971
Publication Date
November 14, 1972
Inventor
Joel Henry G
Assignee
Ing C Olivetti & C
IPC
F21v 07/00
G03B 27/02
G03B 27/54
G03B 27/16
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