Patent ID: 8339612
Filing Date: 2012-12-25
Classification: G01B

Abstract:
1. An interferometer for measuring a surface shape of an examined object or a transmitted wavefront through the examined object, comprising: an area light source comprising a large number of small illuminants and a moving diffuser plate arranged at or near the illuminants such that respective rays from the illuminants pass through and are diffused by the rotating diffuser plate; a light-guiding optical system situated relative to the area light source and the examined object such that the area light source and examined object are in an optically conjugate relation with each other, the light-guiding optical system comprising a light-splitting element, a condenser lens, and a collimator lens, wherein the light-splitting element is situated in an optical path between the collimator lens and the condenser lens, the area light source is situated at a front focal plane of the collimator lens, the examined object is situated at a rear focal plane of the condenser lens, and light reflected by the light-splitting element passes through the condenser lens to the examined object; a reference surface situated relative to the light-splitting element, wherein light from the light-splitting element passes to the reference surface; and a photodetector having a sensor surface arranged at a position that is optically conjugate with the examined object, the photodetector detecting interference of light emitted from the area light source and reflected from respective regions of the examined object with light from the reference surface, the sensor surface comprising multiple pixels.