| 摘要 |
PURPOSE:To minimize the size of the titled device and to realize the random selection scan, by controlling the timing of generation for the pulse so that the surface acoustic wave pulses energized from the 1st and 2nd electrodes are superposed on each other only at a certain optional electrode within the 3rd electrode group. CONSTITUTION:When an MOS transistor array 52 is turned on, simultaneous arrival to an electrode 22 is required between the surface acoustic wave pulse which is energized by an electrode 201 and propagates on a piezoelectric substrate 1 and the surface accustic wave pulse which is energized by an electrode 202 and propagates on the substrate 1. The timing of generation is controlled by a pulse generation timing control circuit 7 for the pulse voltage produced from pulse generating circuits 41 and 42 in order to secure the simultaneous arrival of both above-mentioned surface acoustic wave pulses to the electrode 22. In such way, a miniature surface acoustic wave scanner which is capable of a low-speed scan with an optional selection of the row or the column. |
