| 摘要 |
PURPOSE:To obtain a solar radiation sensor which can obtain the excellent light receiving sensitivity for the light from the oblique direction even if the sensor is provided on a flat surface by forming knurling parts for irregular reflection on the inner surface of a filter that is provided at the upper surface part of the case, and setting the light receiving surface of a photodetector at the inclination of the specified angle. CONSTITUTION:A photodetector 4 of a solar radiation sensor is inclined so as to face the forward direction of a vehicle. Therefore, even if the altitude of the sun if not only high but also low, the incident solar radiation through a filter 3 can readily strike on the light receiving surface. At this time, one end of the photodetector 4 is far from the filter 3 than the other end. Therefore, the light receiving sensitivity might be impaired. Since a knurling parts 6 are arranged on the inner surface of a filter 3, however, the light passing through the filter 3 is scattered with the knurling parts 6 and strikes the light receiving surface. Thus, the excellent light receiving state is obtained. Therefore, the solar radiation sensor, characterized by the directivity for the direction other than the directly overhead direction and high light receiving sensitivity when the sensor is provided on a flat surface, is realized. |
