Patent ID: 7620081
Filing Date: 2009-11-17
Classification: H01S

Abstract:
1. A system for real-time linewidth reduction in an optical source, comprising: a laser device comprising a back facet, wherein the laser device receives a modulated input current that is modulated with a data signal and generates an optical output signal; an etalon device adjacent to the back facet of the laser device, wherein the etalon device receives an optical feedback output signal from the back facet of the laser device, and wherein the etalon device monitors the optical feedback output signal for changes in frequency and, if they exist, generates an optical correction output signal; a photo-detector device disposed adjacent to the etalon device, wherein the photo-detector device receives the optical feedback and correction output signals, and wherein the photo-detector device converts the optical feedback and correction output signals into an electrical signal; and a real-time linewidth reduction feedback correction loop coupled to the photo-detector device, wherein the real-time linewidth reduction feedback correction loop receives the electrical signal from the photo-detector device and generates a substantially linear feedback current to correct a linewidth in the optical output signal, wherein the substantially linear feedback current is generated responsive to the electrical signal; wherein the modulated input current is modified by the substantially linear feedback current to maintain a stable linewidth of the optical output signal, wherein the output optical signal is frequency modulated thereby requiring the stable linewidth.