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. 25, 1980
Filed:
Jan. 26, 1978
Applicant:
Inventor:
Darrell T Thompson, Grandville, MI (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
354 20 ;
Abstract
The sensitivity of photographic materials is measured by a device that generates a controlled exposure of light of predetermined color characteristics. Color control is maintained by subjecting an electroluminescent light source to excitation by alternating current voltages at particular frequencies selected with reference to the light souce color response.