Chromatic confocal measurement apparatus

摘要

PROBLEM: Providing a confocal measurement apparatus that can achieve high measurement accuracy. MEANS FOR SOLVING PROBLEM: A confocal measurement apparatus includes 101 a light source 21 that emits light having a plurality of wavelengths; a diffractive lens 1 that generates a chromatic aberration in the light emitted from the light source 21; an objective lens 2 that collects the light, in which the chromatic aberration is generated, on a measurement target 200; a pin hole (optical fiber 11) that allows passage of the focused light; and a measurement part (spectroscope 23 and imaging element 24) that measures a light intensity in each wavelength. The diffractive lens 1 includes a diffraction surface 1 a in which a diffraction pattern is formed in order to generate the chromatic aberration; and a plane 1 b that is located on an opposite side to the diffraction surface 1 a. In the plane 1 b of the diffractive lens a, a circular light shielding film 4 is disposed around an optical axis X of the diffractive lens 1.