The following figure shows a detection system that uses a 2-part photodiode. Sensing is based on the principle of triangulation, which states that where the beam is concentrated depends on the distance to the sensing object. The light reflected from the sensing object is concentrated on the Receiver. The Receiver in the Sensor is either a 2-part photodiode or a position detector. Positioning the beam on an object is simple with models that emit visible light because the beam is visible. This property can be used to detect colors.

The rate at which an object reflects or absorbs light depends on both the wavelength of the emitted light and the color of the object. There is little chance of damaging sensing objects or Sensors because objects can be detected without physical contact. These developments enable detecting very small objects, as well as precise position detection. The incredibly high resolution achieved with these Sensors derives from advanced design technologies that yielded a very small spot beam and a unique optical system for receiving light. The response time is extremely fast because light travels at high speed and the Sensor performs no mechanical operations because all circuits are comprised of electronic components. This means they can be used to detect virtually any object, including glass, plastic, wood, and liquid. These Sensors operate on the principle that an object interrupts or reflects light, so they are not limited like Proximity Sensors to detecting metal objects. This is impossible with magnetic, ultrasonic, or other sensing methods.Ģ. A Through-beam Sensor, for example, can detect objects more than 10 m away.

Laser beem 3 wide at 100 feet