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:
Mar. 21, 1978
Filed:
Jan. 13, 1977
Applicant:
Inventors:
Robert E Levin, South Hamilton, MA (US);
Robert P Bonazoli, South Hamilton, MA (US);
Assignee:
GTE Sylvania Incorporated, Stamford, CT (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03B / ; G03B / ;
U.S. Cl.
CPC ...
353 38 ; 353 55 ; 353 97 ; 353 98 ; 353D / ; 362294 ;
Abstract
An overhead projection system which includes a planar lens assembly having two concentrically-oriented condensing lenses. The outer lens has a greater focal length than the inner lens to receive light reflected from the system's reflector while the inner condensing lens receives direct lighting from the system's light source. Accordingly, the inner lens images the light source at the projection lens of the system and the outer lens images the virtual image of the light source.