A field-widened Michelson interferometer designed to measure upper atmospheric winds at three altitudes near the mesopause by using airglow emissions from O1S, OH, and O2 is described. A very large path difference (11 cm) is used to suppress the fringes from the hot F-region emission of O1S and to facilitate accurate measurements. Field widening and thermal compensation are achieved over the large spectral range (557.7–866.0 nm) by the use of three types of glass in the interferometer’s arms. The instrument was installed at Resolute Bay, Canada (74.3 N, 94.5 W), in November 1992 and has been operated remotely from Toronto for four winter seasons. Some examples of data are shown to illustrate ERWIN’s performance.
© 1996 Optical Society of America
Original Manuscript: September 5, 1995
Revised Manuscript: December 18, 1995
Published: June 1, 1996
W. A. Gault, S. Brown, A. Moise, D. Liang, G. Sellar, G. G. Shepherd, and J. Wimperis, "ERWIN: an E-region wind interferometer," Appl. Opt. 35, 2913-2922 (1996)