De scrip tion The OP950 device consists of a PIN silicon photodiode molded in a clear epoxy package which allows spectral response from visible to infrared light wavelengths. The wide receiving angle provides relatively even reception over a large area. The side-looking package is designed for easy PC board mounting. This photodiode is mechanically and spectrally matched to Optek’s GaAs and GaAlAs series of infrared emitting diodes.