Patent ID: 8259305

Claim:
A surface shape measuring system, comprising: an illumination unit including a main light source, a focusing lens, and a projection lens; a beam splitter to split illumination light emitted from the illumination unit into beams respectively irradiated onto a reference surface of a reference mirror and a measurement surface of a target object to be measured; a light detecting element to capture an interference pattern generated by the interference of a reference beam and an object beam respectively reflected by the reference surface and the measurement surface; and a control computer to obtain surface shape data through white-light interference pattern analysis from an image captured by the light detecting element and detect whether or not the measurement surface is defective from the obtained data, wherein a subsidiary light source to provide falling illumination to the target object is provided between the target object and the beam splitter; and two-dimensional data and three-dimensional data regarding the surface shape of the target object are obtained by selectively intermitting the turning-on of the main light source and the subsidiary light source and the irradiation of the illumination light onto the reference surface, wherein a mechanical shutter to selectively intermit the irradiation of the illumination light onto the reference surface is provided between the beam splitter and the reference mirror, wherein the subsidiary light source includes: a ring-shaped body and a plurality of light emitting diodes provided along the inner circumferential surface of the ring-shaped body, wherein the main light source includes: an illumination panel and a plurality of light emitting diodes arranged in a matrix shape on the illumination panel.