retrorefleks

Retrorefleksjon is an optical phenomenon where light is returned in the direction from which it originated. This occurs due to the reflective properties of a surface or a material. Unlike a simple mirror which reflects light at an equal angle to the incident ray, a retroreflector returns light directly back to the source, regardless of the angle of incidence.

The most common form of retroreflector is the corner-cube reflector, often called a trihedral retroreflector. This consists of three mutually perpendicular reflective surfaces. Light entering the corner is reflected by each of the three surfaces in turn, exiting parallel to its original path. Another type of retroreflector is a cat's eye reflector, which uses a lens to focus light onto a reflective surface and then re-collimates it back towards the source.

Retrorefleksjon has numerous practical applications. It is widely used in traffic signs, road markings, and vehicle reflectors to improve visibility at night or in poor weather conditions, enhancing safety. In surveying and geodesy, retroreflectors are used with lasers for precise distance measurements. They are also employed in applications such as optical communication, target designation, and in some types of sensors. The efficiency of retrorefleksjon is a key factor in its effectiveness in these various fields.