| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a photosensor capable of reducing the manufacturing cost compared to the case plural kinds of photosensors are used and enhancing the design feature of an electric apparatus mounted therewith. <P>SOLUTION: The photosensor 1 includes: light receiving elements 2v and 2i each having different spectral sensitivity; amplifier circuits 3v and 3i for each amplifying the signals detected by the light receiving elements 2v and 2i; an arithmetic circuit 4 that calculates a sum of/difference between the detected signals each amplified by the amplifier circuits 3v and 3i. The amplification ratio of the amplifier circuits 3v and 3i is adjustable, and the calculation of the arithmetic circuit 4 is changeable. By adjusting the amplification ratio and by changing the calculation, the wavelength region of a beam of light to be detected can be switched between two wavelength regions. Accordingly, compared to the case two or more photosensors are used, the number of the photosensors can be reduced and various component parts can be commonly used. As a result, the manufacturing cost can be reduced and a smaller area is required for mounting the same to an apparatus resulting in a well design feature of the apparatus. <P>COPYRIGHT: (C)2013,JPO&INPIT |
