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. 03, 1989
Filed:
Sep. 02, 1988
Bruce A Richardson, Nepean, CA;
Northern Telecom Limited, Montreal, CA;
Abstract
In a method and apparatus for stabilizing the emission spectrum of a semiconductor laser diode, an external optical cavity is coupled to the laser diode to couple light from an active region of the laser diode to the external cavity and from the external cavity to the active region of the laser diode. The phase of light coupled from the external cavity to the active region of the laser diode is dithered about a phase operating point at a dither frequency. A component of the forward voltage across the laser at the dither frequency is sensed and a feedback signal indicative of the amplitude of said component of the forward voltage and the phase of said component of the forward voltage relative to the phase of the dither is generated. The phase operating point is changed in response to the feedback signal to minimize the amplitude of said component of the forward voltage. The method and apparatus are useful for stabilization of laser diodes used in high performance optical communications systems.