| 摘要 |
<p>PROBLEM TO BE SOLVED: To achieve a higher accuracy of height calculation by a method wherein a photodetecting surface for reflected light is reduced using slits and a pinhole and reguarly reflected light alone can be received to accurately determine the position of the slit rotating. SOLUTION: By the adjustment of the overall height of a scanning mechanism 13, a light shielding zone 10 is rotated by a rotation mechanism 12 to irradiate a laser light 2A to that positioned at a reference height so that the reflected laser light 2B passes almost at the center of a lens 3. Thereafter, the two laser lights are moved on wires 20 by a scanning mechanism 13 to the direction in which a plane containing the optical axes of the two laser lights 2A and 2B is vertical to the wire 20. As a result, the reflected laser light 2B reaches a photodetector 4 in a state where the position of slits 11 differs with respect to the lens 3 according to the height of the wires 20. Receiving an output signal from the photodetector 4, an arithmetic processing mechanism 14 reads an output signal of the rotation mechanism 12 at the moment to determine the position of the slits individually. Thus, the height of the individual wires 20 can be calculated from the position of the slits 11.</p> |
