Retroreflection, also called night visibility, is a specific type of light reflection when the light rays goes on a surface and comes back to the...

Retroreflection, also called night visibility, is a specific type of light reflection when the light rays goes on a surface and comes back to the source of light. This principle is a pillar in road safety. Indeed, the vehicles lamps during the night enable to see the road markings, road signs and conspicuity tapes. A retroreflectometer is used to measure the retroreflection performance of the surface. The retroreflection (often written “R”) is measured in cd. m^-2. lx^-1.