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:
Oct. 12, 1976
Filed:
Dec. 23, 1974
Applicant:
Inventor:
David S Cochran, Palo Alto, CA (US);
Assignee:
Hewlett-Packard Company, Palo Alto, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G09F / ;
U.S. Cl.
CPC ...
340335 ; 340336 ;
Abstract
This specification describes a power control circuit for reducing the brightness of multi-segment light-emitting diode (LED) characters in proportion to the number of segments illuminated to compensate for the apparent greater brightness of those characters having more segments illuminated than others. Since brightness is a function of power, the power required to drive multi-segment characters is substantially reduced, which extends useful battery life of battery powered equipment having light-emitting displays. Since less power is required by the display, the power driving and dissipation capability of the drive circuitry is also reduced.