The HOA1879 series consists of an infrared emitting diode facing an NPN silicon phototransistor encased in a black IR transmissive thermoplastic housing. Detector switching takes place whenever an opaque object passes through the slot between emitter and detector. The HOA1879 series employs an IR transmissive housing which features smooth optical faces without external aperture openings; this feature is desirable when aperture blockage from airborne contaminants is a possibility. The HOA1879-011 and -012 have a 0.060 in (1.52 mm) dia. detector aperture, while the HOA1879-015 has a 0.010 in (0.25 mm) x 0.040 in (1.02 mm) vertical aperture in front of the detector. This feature is ideal for use in applications where maximum position resolution is desired. The HOA1879 series employs plastic molded components. For additional component information see SEP8506 and SDP8406.
Housing material is IR transmissive polysulfone. Housings are soluble in chlorinated hydrocarbons and ketones. Recommended cleaning agents are methanol and isopropanol.