The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 11, 1986
Filed:
Mar. 17, 1983
Applicant:
Inventor:
Richard L Cohen, Matawan, NJ (US);
Assignee:
Allied Corporation, Morristown, NJ (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
3502 / ;
Abstract
A directional filter is constructed with a plurality of grooves (15) extending into a plate (13) from one side (16) thereof. The grooves (15) have a light absorbing characteristic which causes them to absorb light impinging upon the grooves, particularly light impinging upon the grooves (15) from within the plate (13). Since all light passing beyond a certain angle .phi. must impinge upon the grooves (13), and only a small percentage of light passing parallel to the cut of the grooves (15) would impinge upon the grooves (15), the filter has a high ratio of attenuation of unwanted versus wanted light.