Patent ID: 9588043
Date: 2017-03-07
CPC Classifications: G01N

Claim:
1. A measurement apparatus comprising: a sensor that photoelectrically converts received light to output image data; a lens that condenses light reflected by an object surface to be measured on the sensor; a lens control unit configured to control aperture angles of rays passing through the lens so that the aperture angles of the rays incident on the sensor are different; a measurement control unit configured to control the sensor and the lens control unit so as to acquire a multi-angular reflectance property in a neighborhood of a specular reflection direction of the object surface; a stage on which an object to be measured is placed; and a stage control unit configured to control a tilt of the stage, wherein the stage control unit changes the tilt of the stage in accordance with a declination angle instructed by the measurement control unit, and the sensor outputs image data corresponding to the declination angle, wherein the measurement control unit acquires a reflectance property of the object surface corresponding to the declination angle from the image data corresponding to the declination angle, and wherein the lens has object-space telecentricity, the sensor is an area sensor in which light receiving elements are arranged two-dimensionally, and the reflectance property represents a two-dimensional distribution of reflectances in the object surface.