[OPTICAL REVIEW Vol. 2, No. 4 (1995) 319-322]

Measurement of Dihedral Angle Errors of a Large-Aperture Space Retroreflector: Separation of the Effect of Sag Due to Gravity

Atsushi MINATO,1 Nobuo SUGIMOTO,1 Zvi BLEIER,2 George C. HUNTER3 and James PAUL3

1National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki, 305 Japan, 2PLX, Inc., 40 West Jefryn Blvd. Deer Park, NY 11729, USA, 3Zygo Corporation, Laurel Brook Road P.O. Box 448, Middlefield, Connecticut 06455-0448, USA

(Received January 20, 1995; Accepted May 16, 1995)

A 50-cm diameter hollow cube-corner retroreflector for a space application was tested with a 60-cm interferometer. To separate the effect of sag due to gravity, the interferograms were taken at six rotational positions, with the retroreflector mounted horizontally. The zero-gravity dihedral angles and the effect of sag were estimated from the interferograms.

Key words : cube-corner retroreflector, optical test, interferometer, space retroreflector, zero gravity