| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a coordinate input system capable of reducing the degree of tailing or fading regardless of machines. <P>SOLUTION: The coordinate input system includes light sources within two optical units 2, installed in different positions on a touch panel for emitting light in the form of a fan approximately parallel to the face 1 of the touch panel and about each position of installation; a reflecting part 3 installed on the touch panel for reflecting the light from each light source back to each light source; and light receiving parts installed within the optical units 2 for receiving the light reflected from the reflecting part 3. When the light is blocked by a blocking object, the coordinate input system detects the coordinates of the blocked position. When a value that varies depending on the blocked position is to be set as the threshold of a signal level for detecting dips in the signals detected by the light receiving parts, the amount of dips which serves as the basis for calculating the threshold is sampled in advance for each machine and a threshold characteristic of each machine is set using the amount of dips. <P>COPYRIGHT: (C)2004,JPO</p> |
