Background Luminance Sensor LM21

Intelligent, stand-alone Background Luminance Sensor (An Ambient Light Sensor) for Runway Visual Range (RVR) and ICAO airport visibility systems. Easy to integrate with Vaisala LT31 and FS11 sensors.

Intelligent, stand-alone sensor
Verified accuracy and photopic response
Extensive self-diagnostics
Window contamination measurement and compensation
Optical path blockage detection
High power heaters to prevent snow accumulation
Calibration traceable to measurement standards
Field calibration device available
Easy to calibrate
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Key Benefits

Easy to calibrate
The calibration of LM21 is traceable to international measurement standards for luminous intensity. Calibration starts automatically when Vaisala Field calibrator LMA21 is connected to LM21.
Resembles Human Eye
LM21 is a precision photometer with a verified photopic spectral response. It measures the total amount of light coming in from an angle of 6 degrees, and converts the measured data to cd/m2.
Comprehensive Self-Diagnostics
LM21 is an intelligent, standalone sensor. To ensure reliable and uninterrupted operation, it has extensive self-monitoring functions with high power heating features.