摘要 |
The interference optical system includes a light source, a collimator, a light-receiving element, a tunable filter, and a calculation apparatus. The collimator emits measuring light from the light source to a first main surface of the object, and receives reflected light from the first main surface and a second main surface. The light-receiving element acquires an intensity of light from the collimator. The tunable filter sweeps a wavelength of the light incident to the light-receiving element. The calculation apparatus measures an interference intensity distribution that has wavelength dependence and is an intensity distribution of the reflected light from the first main surface and the second main surface, and measures the thickness or the temperature of the object based on a waveform obtained by Fourier transforming the interference intensity distribution. |