Patent ID: 9091534
Filing Date: 2015-07-28
Classification: G01B,G01J,G01M,Y10T

Abstract:
1. A measuring apparatus, comprising: a light source for emitting light having a coherence length smaller than an optical path difference between light entering a first optical surface of an object to be measured and light entering a second optical surface of the object to be measured; a separating optical system for separating the light emitted from the light source into reference light and measuring light that irradiates the object to be measured; a lens array formed of a plurality of lenses, for condensing, on an image plane, each of the reference light and the measuring light that travels via the object to be measured; an image pickup element arranged on the image plane; an adjusting unit for changing at least one object to be adjusted among an optical path length of the measuring light that travels from the light source to the lens array, an optical path length of the reference light that travels from the light source to the lens array, and a wavelength width of the light source, the adjusting unit being configured to change the at least one object to be adjusted so as to include a range in which a signal light component contained in the measuring light that travels via the object to be measured interferes with the reference light; and a calculating unit for extracting interference light spots generated through interference between the signal light component and the reference light from a plurality of picked-up images acquired sequentially from the image pickup element while changing, by the adjusting unit, the at least one object to be adjusted, calculating positions of the interference light spots, and calculating a shape of the object to be measured based on the positions of the interference light spots and predetermined reference positions.