RL and QD retroreflectometer measurements
DELTA’s successful line of handheld retroreflectometers for pavement stripes includes the LTL-XL model supporting not only night visibility (RL), but also daytime visibility (QD). Where RL is a measure of retroreflected light, the QD is a measure of diffuse illumination during daytime. No adjustments are called upon when measuring white and yellow markings. In addition, the retroreflectometer shows and stores day, time, humidity and temperature, as well as road ID, marking type and user ID.
The instrument comes with maintenance-free LED light. RL and QD can be measured under “dry” and “wet” conditions.