Hollow Retro-Reflector

Hollow Retro-reflectors are hollow corner cube retroreflectors which use 3 Plano (flat) surfaces to form the corner cube geometry.  Hollow Retro-Reflectors eliminate the effects of the index of refraction and also the entrance surface of a traditional corner cube.  This makes them very useful over wide wavelength ranges and wide wavelength ranges.  They are also much lighter weight than a comparable size solid corner cube prism.