MULTI-OPTICAL AXIS PHOTOELECTRIC SENSOR

摘要

PURPOSE: To allow the sensor to confirm presence of a thin flat object and abnormity in which number of optical axes is increased without increasing number of light emitting elements and light receiving elements by conducting optical sensing between a light receiving section and a light emitting section opposite to each other of a same stage at first scanning and conducting optical sensing in an oblique way between a succeeding light receiving section and a light emitting section of the same stage at second scanning. CONSTITUTION: A light emitting device 1 has plural light emitting sections 1a-1n each comprising a light emitting diode or the like. Alight receiving device 2 is provided with plural light receiving sections 2a-2n each comprising a photodiode or the like opposite to each of the light emitting sections 1a-1n. Then a light emitting timing of the light emitting section 1a is synchronously with the light receiving section 2a and the sensing by the sections 1b to 1n and 2b to 2n opposite to each other is sequentially conducted. Then the sensing by means of oblique position relation where the light receiving section 2b receives a light from the light emitting section 1a is sequentially conducted and one period of this oblique sensing is finished when the light receiving section 2n senses the light emitted by the light emitting section 1n-1 and then the processing above is repeated.