A safety light curtain (also known as a safety grid) is a device that uses photoelectric sensing to provide safety protection. Its core operating principle is as follows:
1. Basic Structure
Transmitter: Consists of multiple infrared emitting diodes arranged at equal distances, continuously emitting invisible infrared light beams.
Receiver: Arranged in parallel with the transmitter, accurately receives each infrared light signal.
Control System: Monitors the beam status in real time and triggers safety responses.
2. Workflow
Beam Formation
The transmitter generates parallel infrared beams, forming a dense “light curtain barrier” within the hazardous area.
The beam spacing is adjustable (typically 5-20mm) to meet varying safety requirements.
Light Blockage Detection
When an object (such as a person or tool) enters the light curtain area, the beam is partially blocked.
The receiver immediately detects the signal interruption, responding with millisecond-level accuracy.
Safety Response
The control system receives the light blockage signal and triggers an emergency stop or alarm.
Typical applications include press shutdown and elevator door pinch protection.
3. Technical Features
Infrared Technology: Utilizes 850nm or 940nm invisible light to avoid interference.
Multi-beam Collaboration: Triggers when a single beam is blocked, ensuring comprehensive protection.
Anti-interference Design: Uses modulation frequency to detect ambient light interference.
4. Typical Application Scenarios
Industrial Machinery: Punching machines, injection molding machines, and robot workspace protection.
Public Facilities: Elevator door anti-pinch, automatic door safety monitoring.
Logistics Systems: Conveyor Belt Foreign Object Detection.
This technology achieves rapid response through non-contact detection, making it a key protection measure in industrial safety.
