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:
Aug. 03, 1993
Filed:
Aug. 24, 1992
Milton R Latta, San Jose, CA (US);
Timothy S Gardner, Tucson, AZ (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An optoelectronic system for controlling laser drive current to produce a power level at the target independent of changes in the transmissivity of a beamsplitter positioned in the optical path between the laser source and the target. A second beamsplitter with transmissivity and reflectivity factors matched to the first beamsplitter is used to direct portions of light to two photodetectors. The two photodetectors are connected to circuits which produce a signal proportional to the power transmitted by the first beamsplitter divided by the power reflected by the second beamsplitter, that quotient multiplied by the sum of the photodetector signals to produce a final detection signal which is used as input to the servo control of laser drive current.