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:
Dec. 17, 1991
Filed:
Mar. 05, 1990
Henry L Pfizenmayer, Phoenix, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
An amplitude modulated optical signaling system having improved linearity and reduced distortion is provided by detecting a portion of the optical output from the light emitter to obtain an electrical feedback signal and phase reversing a first portion of the feedback signal and degeneratively combining it with the electrical input signal of the system to obtain a combined signal for ac modulating the light emitter. A second portion of the feedback signal is desirably time averaged and used to control the dc drive to the light emitter so that the average light output is substantially constant. The distortion otherwise introduced into the optical signaling system by the non-linearity associated with optical emitters driven at high power levels is reduced.