| 摘要 |
PROBLEM TO BE SOLVED: To provide a photoelectric sensor for distance measurement for measuring the distance of an object in a monitoring area.SOLUTION: A sensor 1 includes: a beam emitting device 6 for emitting an origination beam; a beam receiving device 8 for generating a reception signal 18 from the original beam reflected by an object in a monitoring area; an A/D converter 10 for sampling the reception signal; and an estimation unit 12 for evaluating the reception signal. The origination beam is periodically transmitted, and the reception signal is periodically sampled. A storage part 14 is provided for storing the reception signal, and a reference reception signal 20 is stored therein. The evaluation unit compares the reception signal with the reference reception signal, and outputs an object confirmation signal to a signal output part 16. The object confirmation signal shows whether an object is an acceptable object 22 or an unacceptable object 24 depending on whether the reference reception signal coincides with the reception signal. The evaluation unit confirms a length of the object using a preliminary scan reception signal 26 in a first step, and then, newly scans the length of the object, and confirms the reference reception signal of a contour of the object.SELECTED DRAWING: Figure 2 |
