Photoacoustic Spectroscopy is a sensitive technique for measuring small absorptions that is mainly applied when minute concentrations of molecular species have to be detected in the presence of other components at higher pressure. It has become a powerful technique to study concentrations of gases at the part per billion or even part per trillion levels. It is based on the photoacoustic effect. The absorbed energy from the sunlight is transformed into kinetic energy of the sample by energy exchange processes.
Photoelectric Control is an industrial device composed of a light transmitter and light receiver. The transmitter directs light towards the object and the receiver is pointed towards the object and detects the pressure or absence of reflected light originating from the transmitter. These have a wide variety of methods to detect an object. They are used where physical contact is not needed or desired. They cover a broad spectrum of controls.
Photoelectric sensors are designed to provide specific process tracking, position information, and part quality solutions in all areas of the automation process. The parts of photoelectric sensor include a light emitting diode (LED), a light sensitive phototransistor (photo cell), and a slotted disc called a light beam interrupter. These are especially suited for applications in robotics, assembly, and material handling.