Photoelectric sensors are sensors used to detect an object’s colour and distance. These sensors are location sensors that use diodes that emit light as the source of light. The sensor operates on the theory that light is transmitted to an object from the sensor, after which the light is again reflected back to the photoelectric sensor. The sensor is able to measure the distance the target is away from it based on the time it took for the light beam to reach the object and be reflected back.
Article source: https://www.bharatbook.com/report/884084/photoelectric-sensor-market-outlook-industry-insights-opportunity-evaluation