Development of Fabry-Perot interferometers for airglow observations

We are developing an all-sky and a scanning Fabry-Perot interferometer for studying the dynamics of the thermosphere and the mesosphere in the polar region. Our instruments have three unique features useful for airglow observation; (1) Each instrument can obtain interference fringes at two different wavelengths at a time using a dichroic mirror, (2) The instruments can observe very weak airglow with the aid of a photon counting imager, (3) When operated simultaneously, the all-sky and the scanning Fabry-Perot interferometer can observe vertical winds in addition to two-dimensional atmospheric motions. We have made two test observations at the Zao observatory, Tohoku University in 1994,and at the Shigaraki observatory, Kyoto University in 1995