Apparatus for measuring thickness

摘要

A thickness measurement apparatus includes a 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; a second lens part for condensing a ray to the object to be measured; an interference light detector for detecting an interference signal generated by the reflected ray and reference ray; a spectroscopic detector corresponding to the second lens part to form a light path different from the path formed by the interference light detector and splits the ray reflected by the measurement object to detect an intensity and wavelength of each split ray; and a light path converter for selectively transmitting a ray to the interference light detector or spectroscopic detector, wherein position exchanging is performed between the first second lens parts.