LUMINANCE ADJUSTING METHOD, IMAGE READING DEVICE, LUMINANCE CALIBRATING SEAL FOR USE IN THE IMAGE READING DEVICE, COLOR DISCRIMINATING METHOD AND COLOR DISCRIMINATING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide: a luminance adjusting method, which discriminates colors by digitization of colors using an image reading device equipped with image pickup elements having an automatic luminance adjusting function, and in which the image pickup elements adjust and calibrate luminance values measured according to brightness of the images (colors) of the measured object differently from their intrinsic values; an image reading device having a luminance adjusting function; a luminance calibrating seal for use by the image reading device; and a color discriminating method and a color discriminating device both using the image reading device.SOLUTION: In the luminance adjusting method, on the side where an image reading device comes into contact with the measured object, a plane having a white-and-black pattern with white and black parts having different area ratios and whose boundary between the white and black parts so decenters as not to become point-symmetric with reference to the center of the measured image when the image reading device is rotated, and a transparent part or an aperture part for designating a desired color part of the measured object and measuring it as an image is provided at a part on the same plane not including the center of the measured image.SELECTED DRAWING: Figure 1