| 摘要 |
<p>PURPOSE:To provide the titled device with both functions of a tablet device and a graphic display device by forming a tablet structure by a conductive material consisting of horizontal and vertical straight lines and arranging light emitting and photodetecting devices at positions surrounded by intersected points. CONSTITUTION:The tablet structure is formed by linear conductors Lya, L'ya... Lxa, L'xa and light emitting and photodetecting devices are arranged at the positions surrounded by picture elements on these intersected points to constitute the display device. Demultiplexers MP-X, MP-Y supply current successively through resistances and diodes D1x-Dpx, D1y-Dpy of the tablet lines, so that the tablet lines are scanned. When the scanning operation reaches the tablet on the X and Y axes inducing AC to a carsor, AC outputs are obtained from output terminals M1, M2. Since the AC output is detected by 2-3 adjacent lines, the cursor position is calculated from the distribution status of the AC output. Namely, the X axis is scanned and calculated at first and then the Y axis is also processed simularly to fix the coordinates of the cursor.</p> |
