| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an optical position detection apparatus efficiently using a region outside a display screen and detecting stains of an optical retroreflector and/or dust on the optical retroreflector or in its vicinity, and also to provide a recording medium in which its operating program is recorded. <P>SOLUTION: The position of a light shielding object S is detected not only in the display screen 21 but also in the region outside the display screen 21. A position detection function outside the display screen 21 is used to set virtual buttons in the region and detect duct in the periphery of the optical retroreflector 4. On the basis of the levels of light reception signals of optical units 10a and 10b, stains of the optical retroreflector 4 are detected. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
