| 摘要 |
<p>PURPOSE:To reduce a detection range and improve resolving power, by providing a package part covering a light receiving surface with a recessed part, making its recessed bottom narrower than the light receiving surface of a photodetector, and making an aperture of the recessed part wider than the recessed bottom. CONSTITUTION:A recessed part 15 is formed on the light receiving side of a package 13 in which a light emitting element 11 and a photodetector 12 are sealed and unified in a body with light permeating resin. The recessed part 15 is formed in the manner in which the recessed bottom 16 is narrower than the light receiving surface of the light receiving element 12, and the aperture 17 of the recessed part is wider than the recessed bottom 16. In an interrupter constituted in such a manner, the light generated from the light emitting element 11 enters the photodetector 12 side through a detection space 14 of an object. In the light receiving element 12 side, the light which enters the bottom surface 16 of the recessed part 15 formed smaller than the light receiving surface permeates to the light receiving surface, and the other light which enters side surfaces 18 of the recessed part 15 is refracted by the inclination of the side surfaces 18 and does not enter the light receiving surface. Accordingly, a detection range for an object to be detected existing in the detection space 14 is reduced, and excellent resolving power can be obtained.</p> |
