Patent ID: 6909511
Filing Date: 2005-06-21
Classification: G02B

Abstract:
1. An interferometer comprising: a first port for launching an input beam of light; a beamsplitter for splitting the input beam of light into first and second sub-beams, and for directing the first and second sub-beams along first and second optical paths, respectively; tuning plate means positioned in the first optical path; a first reflective surface positioned in the first optical path at a desired distance defining a first optical path length, the first reflective surface for redirecting at least a portion of the first sub-beam for interference with the second sub-beam; fixed plate means positioned in the second optical path; a second reflective surface positioned in the second optical path at a desired distance defining a second optical path length, the second reflective surface for redirecting at least a portion of the second sub-beam for interference with the first sub-beam forming first and second output beams; a second port for outputting the first output beam; and a third port for outputting the second output beam; wherein the tuning plate means is oriented so that the fixed plate means and the tuning plate means provide a desired optical path length difference between the first and second optical path lengths, wherein the first and second sub-beams pass through an unequal amount of soild material in the beamsplitter creating an optical path mismatch; and wherein the tuning plate means and the fixed plate means are oriented to compensate for the optical path mismatch.