Patent ID: 6972850
Filing Date: 2005-12-06
Classification: G01B

Abstract:
1. A shape measuring apparatus using an interferometer, comprising: a light source; a condensing lens for condensing temporarily light waves from the light source; a light wave shaping plate in which a pinhole adapted to convert the condensed light waves into an ideal spherical wave and a window provided in the vicinity of the pinhole and adapted to pass therethrough the light wave surface information are formed; at least one lens having a reference surface and a surface to be measured, and arranged on an optical path of the light waves passed through the pinhole, the optical axes of the reference surface and the surface to be measured being decentered from each other, the lens being adjusted in the position where the light waves reflected by the reference surface pass through the pinhole again and the light waves reflected by the measurement surface pass through the window; and image pickup means for making the reflected light reflected from the reference surface to pass through the pinhole again and the reflected light reflected from the surface to be measured to pass through the window interfere with each other, to measure a shape of the surface to be measured.