Editing Corner reflector (section)

==In optics==
[[File:Corner Cube Reflector CCR.jpg|thumb|Corner cube reflector]]
[[Image:ALSEP AS15-85-11468.jpg|thumb|Apollo 15 Lunar Laser Ranging RetroReflector (LRRR) installed on the Moon]]

In [[optics]], corner reflectors typically consist of three [[mirror]]s or reflective [[prism (optics)|prism]] faces which return an incident [[light beam]] in the opposite direction. In [[surveying]], [[retroreflector]] prisms are commonly used as targets for long-range electronic distance measurement using a [[total station]].

Five arrays of optical corner reflectors have been placed on the [[Moon]] for use by [[Lunar Laser Ranging experiment]]s observing a [[laser]]'s [[time-of-flight]] to measure the Moon's orbit more precisely than was possible before.  The three largest were placed by [[NASA]] as part of the [[Apollo program]], and the [[Soviet Union]] built two smaller ones into the [[Lunokhod programme|Lunokhod rovers]].

[[Automobile]] and [[bicycle]] tail lights are molded with arrays of small corner reflectors, with different sections oriented for viewing from different angles.  Reflective [[paint]] for visibility at night usually contains [[retroreflector|retroreflective spherical beads]].
Thin plastic with microscopic corner reflector structures can be used as [[Flagging (tape)|tape]], on signs, or sewn or molded onto [[clothing]].