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. 23, 1996
Filed:
Feb. 28, 1994
David F Welch, Menlo Park, CA (US);
Donald R Scifres, San Jose, CA (US);
Robert G Waarts, Palo Alto, CA (US);
David G Mehuys, Sunnyvale, CA (US);
Amos A Hardy, Tel Aviv, IL;
Ross A Parke, Fremont, CA (US);
SDL, Inc., San Jose, CA (US);
Abstract
An optical amplifier semiconductor device which is differentially pumped and a master oscillator power amplifier (MOPA) device employing such an amplifier. The amplifier allows the light propagating therein to diverge along at least part of its length, and may be a flared amplifier having a gain region that increases in width toward its output at a rate that equals or exceeds the divergence of the light. The amplifier is pumped with a current density at its input end which is smaller than the current density used to pump the output end for maintaining coherence of the beam to high power levels. Differential pumping may be both longitudinal and lateral within the amplifier. A single mode preamplifier section may be optically coupled to the input end of the amplifier. The amplifier input may have a width which is the same as or wider than that of the preamplifier output. The preamplifier may have a constant mode width or may be tapered to alter the divergence of the beams provided to the amplifier section. The laser oscillator in the MOPA device may be a single mode DBR laser diode monolithically integrated on the same substrate as the optical amplifier. Laser sources external to an amplifier chip may also be used. The input portion of the amplifier or the preamplifier section, if present, may be modulated. The laser oscillator might also be modulated if it has a high Q cavity. Tunable laser oscillators are also disclosed.