Apparatus and method for measuring color of a measurement object

An apparatus for measuring color of a measurement object, said apparatus comprising:

• a first radial illumination unit which projects illumination light to a measurement object at a first illumination angle in a plurality of directions different from one another;
• a unidirectional illumination unit which projects illumination light to the measurement object at a second illumination angle in a single direction, the second illumination angle being different from the first illumination angle;
• a first unidirectional light receiving unit which receives a light ray reflected at a first angle .theta.1 from the direction of regular reflection out of illumination light projected from the first radial illumination unit and reflected by the measurement object, and a light ray reflected at a second angle .theta.2 from the direction of regular reflection out of illumination light projected from the unidirectional illumination unit and reflected by the measurement object, the second angle .theta.2 being larger than the first angle .theta.1;
• and
• a processing unit which executes:
• 1) calculation of a color value at the first angle .theta.1 based on an output of the first unidirectional light receiving unit by permitting the first radial illumination unit to project illumination light to the measurement object;
• and
• 2) calculation of a color value at the second angle .theta.2 based on an output of the first unidirectional light receiving unit by permitting the unidirectional illumination unit to project illumination light to the measurement object.