Patent ID: 6606340
Filing Date: 2003-08-12
Classification: H01S

Abstract:
An external cavity laser comprising:a) a dispersion unit; b) a gain element for producing coherent light incident upon said dispersion unit to generate a diffraction beam, c) a tuning reflector for reflecting said diffraction beam back to said dispersion unit such that a first portion of said diffraction beam is further diffracted by said dispersion unit to enter said gain element to thereby selecting a desired wavelength &lgr;L of said coherent light, and a second portion of said diffraction beam is reflected by said dispersion unit to produce a reflected diffraction beam containing said desired wavelength &lgr;L and at least one angularly-separated wavelength &lgr;; d) a physical filtering device for spatially filtering from said reflected diffraction beam said at least one angularly-separated wavelength &lgr;, thereby producing a low-noise laser beam at said desired wavelength &lgr;L.