| 摘要 |
<p>PURPOSE:To obtain an angle detection apparatus in which a detection part to detect light from a light source is installed, in which the relative angle of a light-emitting part to the detection part can be detected and which can be utilized for an input device. CONSTITUTION:A photodetector 23 which has four-split light-receiving parts 23a to 23d is installed in a detection part 20. Beams of light from two light sources which can be discriminated mutually are emitted from a light-emitting part. The beams of light from the respective light sources are narrowed down in a diaphragm port, and a light-receiving face on the photodetector 23 is irradiated with separate beams of rectangular spot light S16, S17. When the difference in a light-receiving output between the individual four-split light-receiving parts 23a to 23d is computed, the center I1 of the beam of rectangular spot light S16 and the center I2 of the beam of rectangular spot light S17 can be found. When an angle of inclination alpha on the X-Y orthogonal coordinates of a line (x) connecting both centers I1, I2 is computed, it is possible to know the angle of rotation with reference to the Z-axis of the light-emitting part and the detection part 20.</p> |
