OPTICAL MEASURING INSTRUMENT

摘要

An optical measuring instrument in which shift of a sample in the direction of optical axis does not affect the result of measurement. In this instrument, as a result of radiating a light with a short coherence length, a light outputted from the sample is supplied through a half mirror to an optical multiplexer/divider so as to be divided into two lights, and frequency modulation is carried out on one of the lights with a total reflection mirror which minutely fluctuates. Then, a light formed by multiplexing the frequency-modulated light and the other light is led into a detector, where optical characteristic data of the sample are calculated on the basis of an output of the detector.