The HOA1886 series consists of an infrared emitting diode facing an NPN silicon phototransistor (HOA1886- 011, - 012) or photodarlington (HOA1886- 013) encased in a black thermoplastic housing with IR transmissive inserts which form the optical windows. This arrangement provides excellent protection against ambient light while eliminating aperture openings which could be clogged by airborne contaminants. Detector switching takes place whenever an opaque object passes through the slot between emitter and detector. The HOA1886 series employs plastic molded components and has a 0.050 in.(1.27 mm) x 0.060 in.(1.52 mm) vertical aperture in front of the detector. For additional component information see SEP8506/8706, SDP8406, and SDP8106.