Patent ID: 6707553
Filing Date: 2004-03-16
Classification: G01J,G01N

Abstract:
A measurement apparatus for measuring color of an object, comprising:a main body having an opening opposed to an object to be measured; a plurality of illuminators for illuminating a surface of the object in directions different from one another; a light detector for detecting reflected light in a specified direction from the object illuminated by the plurality of illuminators and outputting light detection signals corresponding to light intensities; a first calculator for calculating reflection characteristic measurement values of the measurement object in correspondence with the plurality of illuminators based on the light detection signals; a storage device for storing an approximate function having an angle of an illuminating direction with respect to a reference direction as a variable in a condition that a direction symmetrical with the specified direction with respect to a center axis of the main body in parallel to a normal to the opening is defined as the reference direction, and having a plurality of undetermined coefficients including an angle of inclination of the center axis of the main body with respect to a normal to the surface of the object; and a second calculator for determining the plurality of undetermined coefficients based on the respective reflection characteristic measurement values and the angles of the illuminating directions, and correcting the respective reflection characteristic measurement values using the approximate function whose undetermined coefficients are determined.