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:
Jul. 13, 1999
Filed:
Apr. 02, 1997
Applicant:
Inventors:
Robert Ralph Turnbull, Holland, MI (US);
Robert Charles Knapp, Coloma, MI (US);
David Joseph Schmidt, Holland, MI (US);
Assignee:
Gentex Corporation, Zeeland, MI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
2502 / ; 2502 / ; 250206 ; 315 82 ; 359265 ;
Abstract
A system and method for optimizing the signal range of a photocell for all ambient lighting conditions. A switched resistor circuit is serially connected to the photocell. The duty cycle of the switched resistor circuit is controlled to provide an optimal signal range for the photocell in both light and dark ambient light conditions.