The opposite photoelectric switch consists of a transmitter and a receiver, which are placed on two sides and installed oppositely. The light beam emitted by the transmitter is aimed directly at the receiver. When an object blocks the light beam, the signal of the receiver changes, thus detecting the object. It has long detection distance, high precision and good stability.

Application: conveyor belt object detection, such as package counting in logistics industry; In the automatic production line, it is used to detect whether the workpiece passes through the designated position; It is also used for perimeter protection in security field, such as fence intrusion detection.

The transmitter and receiver of reflective photoelectric switch are on the same side. The transmitter sends out a light beam, which is received by the receiver after being reflected by an object. When the intensity of reflected light changes, it is judged whether the object exists. It is convenient to install and occupies little space.

Application: in the vending machine, detect whether the goods fall; In the elevator door system, whether there are obstacles between the doors is detected; It is also applied to the detection of vehicles in and out of parking lots and the identification of vehicle positions.