What is a Measuring Light Curtain and how does it work in industrial automation?
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- Issue Time
- Jul 2,2026
A measuring light curtain is an array of parallel infrared light beams emitted from a transmitter to a receiver. When an object enters the beam field, the system instantly detects which beams are blocked and calculates the object's size, position, and profile with high precision.
How It Works
The system operates on a through-beam photoelectric principle. The emitter contains multiple infrared LEDs arranged at fixed intervals (beam spacing), each projecting a beam to a corresponding phototransistor on the receiver side. When all beams reach the receiver uninterrupted, the system registers "no object." When an object interrupts specific beams, the controller processes the beam pattern to determine:
- Object width and height — calculated from which beams are blocked
- Object position — determined by the location of interrupted beams along the array
- Object profile — mapped by scanning the beam interruption pattern over time
Key Specifications
DADISICK DK-QL Series
DADISICK DK-QL series measuring light curtains offer beam spacing options of 2.5mm, 10mm, and 20mm, with detection distances up to 6 meters and protection heights from 77.5mm to 2740mm. All models feature RS485/RS232 communication, 4-20mA analog output, and 1-10V voltage output options, with TUV, UL, CE, RoSH, and GB certifications.
View DK-QL Series Products