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, 1982
Filed:
Nov. 26, 1980
Scott H Early, Indianapolis, IN (US);
David M Savidge, Indianapolis, IN (US);
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Abstract
A display illuminating circuit for a repertory dialer telephone set allows for a subscriber to operate a desired repertory button in low ambient light emergency situations. The circuit illuminates the desired buttons by distinguishable colors of light-emitting elements. Activation of the illumination circuit occurs in response to the telephone set going off-hook and then only for a limited period to conserve battery life. A battery voltage monitoring arrangement provides an indication when a local battery needs to be replaced. In response to an activation signal provided by the voltage monitoring arrangement, the light-emitting elements flash at a level that is detectable by the subscriber going off-hook even in normal ambient light conditions.