Patent ID: 6552801
Filing Date: 2003-04-22
Classification: G01B

Abstract:
An optical interferometer, comprising:a beam splitter that divides incident light into reflected light and transmitted light which travel along respective optical paths, which are orthogonal to each other; a first reflector that subjects said reflected light from said beam splitter to total reflection and directly returns said reflected light to said beam splitter; a photodetector; a second reflector that subjects said transmitted light to total reflection, after which said reflected light and said transmitted light subject to total reflection are merged at the beam splitter into a single ray of light to fall on said photodetector; a third reflector which reflects light from an external source at right angles so as to make said incident light fall on said beam splitter; a fourth reflector which reflects said transmitted light at right angles so as to fall on the second reflector; and a moving member on which said beam splitter and said third and fourth reflectors are mounted and which is movable along an optical path extending between said first reflector and said photodetector.