Wide angle fresnel lens array for infrared motion detector system

Description

The single FIGURE is a front elevational view of a wide angle fresnel lens array for infrared motion detector system showing our new design, the lens array being a flat, rectangular, thin sheet having a front surface with grooves thereon and a plain, smooth, rear surface with no ornamentation.

Referenced Cited
U.S. Patent Documents
1399749 December 1921 Conklin
1970358 August 1934 Bull et al.
3463118 August 1969 Wood
3708222 January 1973 Stern
3883733 May 1975 Nagel
4772094 September 20, 1988 Sheiman
Foreign Patent Documents
968412 February 1958 DEX
2173013A October 1986 GBX
Patent History
Patent number: D315966
Type: Grant
Filed: Nov 7, 1988
Date of Patent: Apr 2, 1991
Assignee: Fresnel Technologies, Inc. (Fort Worth, TX)
Inventors: Richard N. Claytor (Arlington, TX), Russell G. Torti (Fort Worth, TX)
Primary Examiner: Susan J. Lucas
Attorney: James E. Bradley
Application Number: 7/267,788