| 摘要 |
<p>PURPOSE:To apply the optical touch switch device for inputting information through the presence/absence of light shielding to a display device with a large screen by effectively utilizing beams radiated from a light emitting element. CONSTITUTION:The plural pairs of infrared light emitting elements 1 and light receiving elements 2, which are faced each other, are mounted on a printed circuit board 3 provided with a rectangular window 4 at the almost center. In this case, the respective pairs of light emitting elements 1 and light receiving elements 2 are arranged so that an optical axis AB can be longitudinally and laterally passed on the window 4. Further, peripheral light flux out of the optical axis AB is condensed to the light receiving elements 2 by arranging a rectangular infrared filter board 5, which cross section is formed in the shape of a convex lens, around the window 4 so as to be positioned on the front panel side adjacent to all the light emitting elements 1 and light receiving elements 2. Moreover, even back light flux is utilized as well by arranging the concave plane part of a concave reflection board 6 on the back side of all the light emitting elements 1.</p> |
