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:
Apr. 02, 1996
Filed:
Nov. 23, 1994
Applicant:
Inventors:
John F Dreyer, St. Paul, MN (US);
Robert M Fesler, Austin, TX (US);
Dennis F Vanderwerf, Austin, TX (US);
Assignee:
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
353 38 ; 353 63 ; 353D / ; 362241 ;
Abstract
A projection system is described which efficiently combines the output from multiple lamps, images of which are focused to a common point. The projected screen brightness is multiplied over that of a conventional single lamp of equivalent wattage. The screen brightness can be increased or diminished by switching individual lamps on or off, adjusting the light level for conventional overhead transparencies, or low transmission liquid crystal display projection panels.