Rustam Itekov

What is Retroreflector and what is it used for?

A retroreflector is a device that reflects light back along the incident path, irrespective of the angle of incidence. The light is reflected parallel to the direction it came from, but in the completely opposite direction. Retroreflection is used on road surfaces, road signs, vehicles and clothing. When the headlights of a car illuminate a retroflective surface, the reflected light is directed towards the car and its driver, and not wasted by going in all directions as with diffuse reflection.

Who invented the device and when was it invented?

They were invented in 1933 by Percy Shaw of Yorkshire in England.


  • Larger bandwidth
  • Low probability of intercept
  • Immunity from interference or jamming
  • Frequency spectrum allocation issue relief
  • Smaller, lighter, lower power


  • power use
  • speed
  • modulation range
  • compactness
  • retroreflection divergence
  • cost

What kind of retroreflectors are there?

Common types include the corner cube retroreflector, which can send light back long distances and is useful on highways. Other common types are mirrors, paints, tapes, and retroreflective rows, such as those that have been placed on the moon or satellites.


What is Retroreflection? (2012, June 25). Retrieved March 12, 2015, from

Kirmayer, A., & Lingo, A. (n.d.). What is retroreflector? Retrieved March 12, 2015, from

Lunar Retroreflectors. (n.d.). Retrieved March 12, 2015, from