Patent ID: 9551564
Date: 2017-01-24
CPC Classifications: G01B

Claim:
1. An apparatus comprising: a light source unit configured to change a wavelength of light over time; an interference optical system configured to split the light from the light source unit into irradiation light to be applied to an object and reference light and to generate interference light between reflected light of the light applied to the object and the reference light; a light splitting unit configured to split the interference light into two interference lights; two optical detection units configured to receive the two interference lights; an information acquisition unit configured to acquire information about the object on the basis of a temporal waveform of an intensity of the interference lights; a wavelength selector provided on an optical path between an emission end surface of the light source unit and the two optical detection units, and having a wavelength selectivity with equal wavenumber intervals; and a differential detection unit configured to detect a differential between the two interference lights detected by the two optical detection units, wherein the information acquisition unit obtains peak values in the temporal waveform of the intensity of the interference lights and acquires the information about the object on the basis of the obtained peak values, and wherein the wavelength selector is a Fabry-Perot filter.