| 摘要 |
PURPOSE:To enable measurement of color of an object to be measured accurately regardless of any change in light transmissivity due to a bending of a light guide for illumination, by providing a reference plate in an optical path to an object to be measured from the light guide for irradiation in such a manner as to be allowed to advance or retract. CONSTITUTION:A light guide 12 for illumination irradiates an object 16 to be measured with illumination light via an optical path (a). On the other hand, a light guide 14 for receiving light receives reflected light on the object 16 via an optical path (b) to be supplied to a photodetector. In a photometry probe thus arranged, for example, under a condition as indicated by the solid line, a reference plate 18 supplies reflected light therefrom 18 to the photodetector with the guide 14. Then, the reference plate 18 is turned to a position indicated by the dotted line to supply the reflected light from the object 16 to the photodetector. A photometry device body calculates a reflection factor of the object 16 from an output of the photo detector in the case of the reflected light from the object 16, an output of the photodetector in the case of the reflected light from the reference plate 18 and a predetermined constant to determine color of the object 16. |
