04457585 is referenced by 83 patents and cites 18 patents.

A clear, transparent, rigid plastic sheet is bent into an inverted U-shape to provide a top supported by continuous transparent legs. A fresnel lens, coextensive with the top, is secured to the top or actually formed in one of its surfaces to provide a hand-free, self-supporting large area magnifier capable of use in reading a complete printed page with little or no shifting of the magnifier. For various scientific and other purposes, scales, grids, or other reference marks or patterns are carried on transparent elements secured to the bottoms of the legs where they are likewise magnified for counting or measuring or other large area analysis, or study of a full page or document being read.

Title
Magnifier reader
Application Number
6/297980
Publication Number
4457585
Application Date
August 31, 1981
Publication Date
July 3, 1984
Inventor
Gerard M DuCorday
10871 Thorley Rd., Santa Ana, 92705
CA, US
Agent
Gausewitz Carr Rothenberg & Edwards
IPC
G02B 3/08
G02B 7/04
G02B 27/02
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