Patent ID: 6552856
Filing Date: 2003-04-22
Classification: H01S,H04B

Abstract:
A method for locking the wavelengths of a plurality of radiation sources to a wavelength reference, comprising:A) providing at least one etalon that is open within a surrounding enclosure and which includes a gas-tunable medium having a variable optical index of refraction; B) introducing radiation into said etalon, whereby a plurality of equally spaced spectral lines is produced; C) tuning said etalon by varying said variable optical index of refraction of said gas-tunable medium, to align said plurality of spectral lines with said wavelength reference; D) fixing said variable optical index of refraction included in said etalon, so that said spectral line produced remains substantially aligned with said external reference wavelength; E) diverting a portion of the radiation from a radiation source whose wavelength is to be locked, introducing said portion of said radiation into said etalon, whereby at least one spectral line is produced; F) detecting said at least one spectral line output from said etalon and creating control signals therefrom in response to shifts in wavelength of said spectral line output; and G) adjusting said radiation source whose wavelength is to be locked in response to said control signals.