phototransistor
The Toshiba TLP521-1 consists of a photo-transistor optically coupled to a gallium arsenide infrared emitter diode.
EL4N35 Optocoupler IC
EL4N35 Phototransistor Optocoupler IC comes as a dual inline package and has 6 pins.
EL817C Optocoupler/Phototransistor IC
EL817C IC is a popular optocoupler IC. The IC like any other optocoupler consists of an infrared emitting diode which is optically coupled to a phototransistor detector.