| 摘要 |
<p>PURPOSE:To improve the apparent resolution of an optical touch input device by distributing light emitting and photodetecting element trains in multiple stages to magnify the position information detected by the light emitting and photodetecting elements of the front stage while centering on the positions of these elements and repeating the same processing also at the next stage. CONSTITUTION:The light emitting element trains emits light successively by a drive circuit 10 which is controlled by a timing generating circuit 11. The photodetecting element trains 4, 5, 8 and 9 detect the light of their corresponding light emitting elements synchronously with the light emission of said light emitting element trains. A primary deciding circuit 12 decides whether the light is cut off by a touch. Based on the result of this decision, a secondary deciding circuit 13 gives an indication for magnification of the information on a display tube surface in n/m times and n.n/m.m times while centering on the X and Y coordinates which are detected by each element train according to the cut-off information given from the primary light emitting element trains 6 and 7 and the primary photodetecting element trains 4 and 5 or the cut-off information given from the secondary light emitting element trains 6 and 7 and the secondary photodetecting element trains 8 and 9. A display controller 14 magnifies the display tube surface by its information.</p> |
