Newly installed visibility sensor (VS20K) for one of our major customer to deal with the wide variety of road and transport conditions. We have used  Campbell Scientific make CR350 datalogger along with Lufft make VS20k Visibility sensor to provide real-time visibility up to 20000meter.<br>

Visibility is determined by measuring reflectance in accordance with the 42° forward scattering principle. The particles in the field of measurement (e.g. fog droplets) scatter the infrared light emitted by the transmitter. The receiver measures the rate of scattered light from which the reflectance is calculated. Visibility is then computed taking account of the set border contrast.