Measurement speed and accuracy increasing method for use during interferometric measurement of object, involves producing change of optical distance of object arm during exposure of interference images such that images remain unchanged

摘要

The method involves producing a temporally adjusted change of optical distance of a reference arm or an object arm during exposure of respective interference images, so that the change of the optical distance difference between an object (3) and a reference during an exposure time is reduced. The images thus remain unchanged during the exposure time and a selectable optical path difference is produced between the exposures. Independent claims are also included for the following: (1) a method for fast interferometric measurement of an object (2) a method for reducing measurement inaccuracy during an interferometric measurement (3) a device for reducing measurement inaccuracy during an interferometric measurement.