APPARATUS FOR MEASURING THICKNESS

摘要

An apparatus for measuring a thickness, which includes: a first beam splitter for reflecting or transmitting a ray irradiated from an optical source or a ray reflected by a measurement object; a first lens part which condenses a ray to the measurement object and generates a reference ray having a difference of a light path in comparison with a ray reflected by the measurement object; a second lens part for condensing a ray to the object to be measured; an interference light detector which corresponds to the first lens part so as to form a light path and detects an interference signal generated by the ray reflected by the measurement object and the reference ray; a spectroscopic detector which corresponds to the second lens part so as to form a light path different from the light path formed by the interference light detector and splits the ray reflected by the measurement object so as to detect an intensity and a wavelength of each split ray; and a light path converter for selectively transmitting a ray to one of the interference light detector and the spectroscopic detector, wherein position exchanging is performed between the first lens part and the second lens part.