| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a differential detection type photoelectric sensor in which a worst value of a detection target having a lowest light-shielding rate can be determined from among a plurality of detection targets and threshold value setting is facilitated as a result. <P>SOLUTION: A change amount calculation unit 3 calculates a change amount per unit time for the quantity of received light, and a maximum change amount determination unit 5 determines a maximum change amount per detection target. A worst value determination unit 6 determines a minimum value from among the maximum change amounts of a plurality of detection targets. This value is a worst case of a lowest light-shielding rate among the plurality of detection targets, namely, is a minimum value of the maximum change amounts, thereby being useful for setting a threshold value for detection of a detection target. <P>COPYRIGHT: (C)2012,JPO&INPIT |
