Spherical retroreflectors are customarily constructed of cemented hemispheres made from conventional glasses. With the recent availability of glass with a refractive index close to 2 the possibility exists of making such a reflector out of a simple sphere. A refractive index of exactly 2.0 is optimum for reflecting a beam of zero width. For finite beam widths, better overall performance is obtained with an index slightly less than 2.0.
Nakamura, O., Goto, M., Toyoda, K., Takai, N., Kurosawa, T., and Nakamota, T.1994. 'A laser tracking robot-performance calibration system using ball-seated bearing mechanisms and a spherically shaped cat's-eye retroreflector ', Rev of Sci Instruments, 65(4), April, 1006- 1011.
5.
Sugimoto, N., and Minato, A.1994. 'Retroreflector with acute dihedral angles', Optical Letters, 19(20), October, 1660-1662.
6.
Tank, T.1989. 'Pathlength alteration in an interferometer by rotation of a retroreflector', Optical Engineering, 28(2), February, 76-80.
