| 摘要 |
PURPOSE:To certainly detect the moving direction and the moving amount of an object to be detected with high accuracy, by providing at least three light detectors to treat respective detection signals. CONSTITUTION:A plurality of slits 1a are formed at a pitch 3l1 to a disc 1 being an object to be detected secured to one end of the rotor of a reversible motor while light detectors 2-4 each consisting of a light emitting element and a light receiving element are provided at pitches l1 in opposed relation to the slits 1a and detection signals SS1-SS3 form the detectors 2-4 are applied to a control circuit 15. Subsequently, the moving direction of the object to be detected is detected on the basis of the input order of the detection signals inputted to the control circuit 15 while the moving amount thereof is operated on the basis of the number of the inputted detection signals. By this method, the moving direction and the moving amount of the object to be detected can be certainly detected with high accuracy. |
