What is the sensing principle of an Autonics Photoelectric Sensor?
The sensing principle of an Autonics Photoelectric Sensor is based on detecting light changes caused by the presence or absence of an object. These sensors work by emitting a beam of light, usually from a visible red LED or infrared LED, and monitoring how that light behaves when an object passes through or reflects it. When the light beam is interrupted or reflected differently, the sensor converts this optical change into an electrical signal, which is then sent to a control system or PLC. This process allows the sensor to detect objects quickly and accurately without physical contact, making it ideal for use in automation, packaging, and material handling systems.
The through-beam type is one of the most precise sensing methods. In this setup, the emitter and receiver are installed opposite each other. Detection occurs when an object passes between them and blocks the light beam. This method provides the longest sensing distance and the highest detection reliability, even in dusty or oily environments. It is commonly used for long-range detection tasks such as conveyor belt monitoring and product counting in production lines.
In the retro-reflective type, both the emitter and receiver are housed in the same sensor unit, and a reflector is placed opposite it. The light emitted from the sensor bounces off the reflector and returns to the receiver. When an object interrupts this reflected beam, the sensor detects it. This type is easy to install and works well for medium-distance detection, particularly in packaging, logistics, and assembly applications.
The diffuse reflective type detects objects based on light reflected directly from the target’s surface. It doesn’t require a reflector, which simplifies installation and saves space. The sensor emits light toward the object, and when the light bounces back to the receiver, detection occurs. This type is ideal for short-distance applications such as detecting labels, parts, or products on moving belts. Together, these three sensing methods form the core of how Autonics Photoelectric Sensors deliver precise, fast, and reliable detection across industrial automation systems.