| 摘要 |
<p>PROBLEM TO BE SOLVED: To enable the cost to be reduced and discrimination time to be shortened for discerning the authenticity paper sheets. SOLUTION: A light receiving part 3 consists of a linear image sensor, which is placed in the direction vertical to the transportation direction, and an image formation lens, which forms an image of an output light 2a from the light source 2 that transmits paper sheets 1 on the linear image sensor. A surface pattern sensor 4 is composed of the light source 2 and the light receiving part 3. A pattern detection means 5, according to the transportation of paper sheets 1, scans the linear image sensor in the light receiving part 3 at a fixed time interval and intermittently detects the surface pattern of paper sheets 1. Then, an approach detection means 6 obtains output differences between each pixel within the specified range of the linear image sensor, the absolute value or square total value of each output difference. Based on this total value, it is detected that a leading part 1a of paper sheets 1 approaches a scanning line of the surface pattern sensor 4.</p> |
