Patent ID: 6614818
Filing Date: 2003-09-02
Classification: H01S

Abstract:
An optical resonator comprising:a gain medium for generating light of a characteristic frequency spectrum with a peak gain frequency &ugr;g and a peak gain frequency tuning, rate with respect to temperature d&ugr;g/dT, said gain medium defining a physical gain, path length Lg and having a refractive index ng, a thermo-optic coefficient dng/dT, and a thermal expansion coefficient (1/Lg) dLg/dT, wherein T is temperature of said gain medium; a thermally insensitive substrate for supporting said gain medium, said substrate having a negligible thermal expansion coefficient; a high reflector mounted on said substrate; and an optical coupler mounted on said substrate, said high reflector and said optical coupler defining a resonant cavity surrounding said gain medium, said cavity having a temperature-insensitive physical cavity path length Lo and supporting resonance of said light at a plurality of axial mode frequencies, said cavity operating at a particular axial mode frequency &ugr;m closest to &ugr;g and having an axial mode tuning rate d&ugr;m/dT, wherein |d&ugr;m/dT|>|d&ugr;g/dT| when Loo=Lg, and wherein Lo/Lg is chosen so that d&ugr;m/dT is substantially equal to d&ugr;g/dT, whereby axial mode frequency tuning occurs without axial mode hopping.