| 摘要 |
<p>PURPOSE:To improve the position read precision by placing a transparent resistance thin film on the display screen of a display device and preventing the noise due to a picture display driving signal from being mixed with an input signal at the time of input of a designated position on the thin film. CONSTITUTION:A position read means reads a depressed position as an electric signal in response to detection of a depression detecting means based on the period synchronized with a clock signal PHIsf for display driving of a display part. Especially, the read period is so set that the noise component due to the signal for driving of the display part is prevented from being mixed with the read electric signal. That is, since the noise is mixed with a position detection signal by the fall of the clock signal PHIf, which is stably supplied to drive the display device, in this device, the position is detected at sampling points P1 to P3... synchronized with the rise of the clock signal PHIf to prevent the noise from being mixed with the position detection signal.</p> |
