retroreflector
Beam-bouncing prism array
A retroreflector is a surface or device that reflects light back toward its source, regardless of the angle at which the light strikes it.
Corner cubes and glass beads are common retroreflector designs.
Retroreflectors appear on road signs, bicycle reflectors, safety vests, and survey equipment.
Astronauts left retroreflectors on the moon to enable precise distance measurements from Earth using laser ranging.
Sleeveless upper-body garment
- jacketSleeved upper-body covering
- armbandFabric loop worn above elbow
- cyclingRiding on two wheels
- pedestrianOne traveling afoot
jogger · motorcycle · roadside · highway · conspicuity · nighttime · visibility · warning
Light-splitting optical element
- specularMirror-surfaced, image-returning
- diffuseSpread thinly throughout
- beamStructural support member
- laserConcentrated light device
light · incidence · angle · mirror · lens · coating · glass · photometry
Earth measurement science
- targetObject of pursuit
- benchmarkStandard for comparison
- alignmentCorrect relative positioning
- calibrationAdjusting for measurement accuracy
precision · measurement · satellite · Apollo · spacecraft · tracking · navigation
vest
Sleeveless upper-body garment
pedestrian · jogger · motorcycle · roadside · highway · conspicuity · nighttime · visibility · warning · hazard
prism
Light-splitting optical element
- specularMirror-surfaced, image-returning
- diffuseSpread thinly throughout
- beamStructural support member
laser · light · incidence · angle · mirror · lens · coating · glass · photometry · luminous
geodesy
Earth measurement science
calibration · precision · measurement · satellite · Apollo · spacecraft · tracking · navigation
cat-eye
Upswept eyeglass frame shape
sheeting · delineator · panel · strip · patch · decal · film · embedded · molded · array
guardrail
Roadside safety barrier
- barrierObstruction preventing passage
- crosswalkMarked street-crossing zone
- chevronV-shaped line or symbol
milepost · signalization · beacon · bollard
- reflectorsmirror, flat mirror, parabolic mirror, concave mirror, convex mirror
- opticslens, lenses, mirror, mirrors, prism
- Apollo hardwarecommand module, lunar module, Saturn V, service module, lunar rover
- safety gearhard hat, hi-vis vest, safety helmet, safety vest, safety goggles
- cat's eye thingswinged liner, winged eyeliner, flick, liquid liner, kohl
- optical alignmentcollimator, boresight, laser level, theodolite, reticle
retroreflectorplane mirror
Flat reflective surface
mirror · flat mirror · curved mirror · concave mirror · parabolic reflector
retroreflectorabsorber
Thing that takes in
blackbody · light trap · diffuser · transmitter · matte surface