| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide printed matter reading method and device which can precisely judge the authenticity of printed matter without depending on the eyes. SOLUTION: The read area of printed matter obtained by printing by using hue change ink whose hue changes by a visual angle is irradiated from a constant direction. That a measured value obtained by measuring the chromaticity of light reflected at a prescribed reflection angle is a value peculiar to hue change ink is identified. Thus, normal printed matter is verified, reflected light is measured at more than two observation points different in the reflection angles. Then, that the strength of two kinds of designated monochromatic light in reflected light is inverted at two observation points is recognized. Thus, the printed matter read method normally verifies printed matter. The printed matter reader consists of an illumination device irradiating a read area, a light- measuring means consisting of the light-measuring device of two kinds of monochromatic light in reflected light reflected at different angles, a correction means correcting measured light, a comparison/judgement means which compares the strength of a correction value and judges the authenticity of printed matter, a judgement means and a display means displaying a judged result.</p> |
