| 摘要 |
<p>PROBLEM TO BE SOLVED: To simplify the circuit of an optical touch switch device, by decreasing the number of signal lines connected to a light emitting element group and a light receiving element group. SOLUTION: The optical touch switch device is equipped with a 1st pulse generating circuit 4 which generates 1st pulses having an ON time T1 repeatedly in order and a 2nd pulse generating circuit 5 which generate 2nd pulses having an ON time T1/N (N: natural number) in synchronism with the 1st pulses. The light emitting element group 2 and light receiving element group 3 are driven with a combination of the 1st and 2nd pulses generated by the 1st and 2nd pulse generating circuits 4 and 5 to scan a touch operation surface 1 with a light beam.</p> |
