MICHELSON OPTICAL INTERFEROMETER, THERMAL EXPANSION METER USING OPTICAL INTERFEROMETER, AND THERMAL EXPANSION AMOUNT MEASURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a high-sensitivity and high-accuracy Michelson optical interferometer, and a thermal expansion meter using the Michelson optical interferometer.;SOLUTION: This Michelson optical interferometer has a laser oscillator 21; and an interference fringe generation means for allowing each laser light L11, L12 emitted from the laser oscillator 21 and reflected respectively by a sample surface S1 and a reference plane 451 to interfere mutually, and irradiating an irradiation surface 28 with interference light L4 to thereby generate an interference fringe I comprising a plurality of bright and dark patterns. An optical path difference generation means 24 is provided between a laser oscillator 41 and the interference fringe generation means, and the optical path difference generation means 24 is constituted so that each laser light L11, L12 entering the optical path difference generation means 24 makes four round trips between a reference plane 251 and the sample surface S1. The Michelson optical interferometer is constituted so that each laser light L11, L12 interferes mutually from the optical path difference generation means 24.;COPYRIGHT: (C)2007,JPO&INPIT