| 摘要 |
<p>PURPOSE:To provide a reflection type optical sensor which can accurately detect even an object having a mirror characteristic as metal has and an object with a high reflection factor, for example, white paper by lights different in wavelength projecting onto a reflector, reflector having a characteristic of reflecting light with some wavelength intensely, and detecting changes in the quantity of the light received as caused when the object intercepts the reflected light to judge the object. CONSTITUTION:Lights different in wavelength from each other are emitted separately from light emitting elements 1a and 1b and the outgoing lights are combined to be projected to a reflector 3 or an object 8. The reflector 8 has a characteristic with the reflection factor thereof different for each of the outgoing lights with the different wavelengths from the light emitting elements and thus, when the object 8 intercepts the reflected light in the optical path of the light projected and reflected, the quantity of reflected light with the respective wavelengths changes as received with a photodetecting part 2b.</p> |
