Transmissive-type photo-interruptor with molded housing and crosstalk shielding

Abstract

An apparatus for detecting the passing state of a passing object to be detected by using a two-phase output signal has at least two light receiving elements (12a, 12b) and at least two light emitting elements (13a, 13b) which are disposed in such a manner that one light receiving element confronts one light emitting element and the other light receiving element confronts the other light emitting element, in order that even when the thickness of the object of detection is larger than the slit width thereof, light can pass through the maximum of the slit width to maximize quantities of light incident upon the light receiving elements (12a, 12b). In addition, light shielding pieces (22, 23) are provided at the front surfaces of a light receiving side transparent resin block (14) and a light emitting side transparent resin block (15) to prevent cross talk between not-confronting light receiving and emitting elements (12a, 13b) as well as between not-confronting light receiving and emitting elements (12b, 13a).

Dependencies are inferred from the claim text.