Patent ID: 6483956
Filing Date: 2002-11-19
Classification: H01S

Abstract:
A device, comprising:a fiber, coupled to receive a laser beam at a laser frequency, having a fiber cavity formed of two sets of Bragg gratings that are spaced from each other and are reflective at said laser frequency, said fiber having a first index of refraction for an optical polarization along a first direction perpendicular to the fiber core and a second different index of refraction for an optical polarization along a second direction orthogonal to said first direction; a polarization element coupled to said fiber to receive a transmitted laser beam from said fiber cavity and to produce a first beam polarized along said first direction and a second polarized beam along said second direction; a first light detector to receive said first laser beam to produce a first detector signal; a second light detector to receive said second laser beam to produce a second detector signal; and an electronic circuit operable to combine said first and said second detector signals to produce an error signal indicative of a deviation of said laser frequency with respect to a reference frequency defined by said fiber cavity.