Patent ID: 8593615
Filing Date: 2013-11-26
Classification: G01B,G03B,G03F

Abstract:
1. A measurement apparatus for measuring a height of a test surface, the apparatus comprising: an image sensing device including a plurality of detection units arranged along a first direction and configured to detect interfering light formed by measurement light from the test surface illuminated by white light and reference light from a reference surface illuminated by white light; an optical system configured to guide the measurement light and the reference light to said plurality of detection units; and a processing unit configured to calculate the height of the test surface by performing arithmetic processing using data on intensities of the interfering light detected by said plurality of detection units, wherein the reference surface is placed so that differences are generated among optical path differences between measurement light beams from a plurality of measurement points and reference light beams from a plurality of reference points which enter said plurality of detection units, respectively, wherein said plurality of detection units detect the interfering light when the test surface is moved so that a measurement light beam reflected at one measurement point on the test surface enters said plurality of detection units in series along the first direction while the test surface is moved, and wherein said processing unit specifies, using intensity signals of the interfering light detected by the plurality of detection units arranged in the first direction, a peak position of intensity signal of the interfering light in the first direction, and calculates the height of the one measurement point based on the specified peak position.