| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To materialize a signal detecting circuit and a signal detection method for detecting, by the same circuit, an electric signal output by a photo-sensor and an electric signal indicating an ON/OFF state of a mechanical switch which is ON/OFF switchable, and to materialize a state detecting circuit for detecting, by the same circuit, a state of the electric signal output by the photo-sensor and the ON/OFF state of the mechanical switch. <P>SOLUTION: A signal detecting circuit 1 comprises: a driving power source 11 for driving a photo-sensor 21 including a light-emitting element D and a light-receiving element Tr which outputs an electric signal corresponding to the quantity of light received from the light-emitting element D and for applying a voltage to a mechanical switch 22 which is ON/OFF switchable and is connected in parallel between a terminal for power supply to the photo-sensor 21 and a signal output terminal of the photo-sensor 21; and a detection means 12 which is connected to the signal output terminal of the photo-sensor 21 and detects an electric signal output by the photo-sensor 21 and an electric signal indicating an ON/OFF state of the mechanical switch 22. <P>COPYRIGHT: (C)2009,JPO&INPIT</p> |
