| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a transmission photosensor which can be used easily and whose performance can be enhanced by a method wherein the bottom face of a groove part is formed to be an uneven shape with reference to the direction of an optical axis which connects a light-emitting element to a light-receiving element. SOLUTION: A light-emitting element 2 and a light-receiving element 3 are arranged so as to be faced inside a case 1, and a slit 4 and a slit 5 are formed at the case 1 in the front part of its light-emitting part 2a and in the front part of its light-receiving part 3a. The terminal 6 of the light-emitting element 2 and the terminal 7 of the light-receiving element 3 are installed at the outside of the case 1 through respective holes in a read lid 8. The shape of the groove-part bottom face part 1b of a case groove part 1a used to arrange a shielding member 9 in which an opening part is formed is formed to be fine uneven parts whose cross section is mountain-shaped in a direction perpendicular to an optical axis. The uneven parts prevent the reflection in the direction of the light-receiving element 3 of diffused light received by the groove-part bottom face part 1b from the light-emitting element 2. Thereby, a photosensor is electrified, the light of the light-emitting element 2 is cut off/opened with reference to the light-receiving element 3 by the shielding member 9, and an output having a level difference is fetched from the light-receiving element 3. In this case, the light is cut off surely by the shielding member 9.</p> |
