Patent ID: 6469817
Filing Date: 2002-10-22
Classification: G02F

Abstract:
An apparatus for stabilizing an optical interferometer providing operation on a first optical signal having a first wavelength comprising:means for generating a dithering signal; means for generating a second optical signal having a second wavelength that differs from the first wavelength by a factor of two; means applying a portion of said dithering signal to the second optical signal so as to provide a dithered optical signal having a second wavelength that varies in accordance with the dithering signal; an optical interferometer having an optical path length that is tunable, said optical interferometer being responsive to the first optical signal and being operative to develop a first interference pattern when said optical path length is a prescribed value and being responsive to said dithered optical signal and a path length adjustment drive signal and being operative to develop a dithered interference pattern, said dithered interference corresponding to a tuned interference pattern when said optical path length is said prescribed value, said tuned interference pattern causing said optical interferometer to develop said first interference pattern, and corresponding to an out-of-tune interference pattern when said optical path length is not said prescribed value; means responsive to said dithered optical interference pattern and being operative to develop an electronic feedback signal when said tuned interference pattern is not present; and means responsive to a portion of said dithering signal and said electronic feedback signal and operative to produce said optical path length adjustment drive signal, said optical path length adjustment drive signal serving to tune the optical path length until it reaches said prescribed value, thereby producing said tuned interference pattern, whereby said optical interferometer develops said first interference pattern and stabilizes said optical interferometer.