Through-beam photoelectric sensors are a type of optoelectronic device widely used in industrial automation for precise object detection. These sensors consist of a separate emitter and receiver, where the emitter projects a light beam to the receiver. When an object interrupts the beam, the sensor triggers a signal. Known for their long sensing range, high accuracy, and reliability, they are ideal for applications like conveyor belt systems, packaging machinery, and safety barriers. Common variants include visible red light, infrared, and laser-based sensors, with options for different output types (e.g., NPN, PNP, relay). Key features often include rugged housings for harsh environments, adjustable sensitivity, and fast response times.