Fabry-Perot interferometer with a new focal plane detection technique and its application in ground-based measurement of NIR OH emissions

Fabry-Perot interferometer (FPI) is an important instrument to study the composition and dynamics of the mesosphere and thermosphere. Despite the inherent large throughput of FPI, its sensitivity and applications has been largely limited by the use of low quantum efficiency and limited spectral range photomultiplier tubes. The high quantum efficiency CCD has gained wide acceptance in recent years. CCD is almost an ideal detector, it has high quantum efficiency and wide spectral range from UV to NIR, but its square format is not compatible with the circular fringe pattern generated by the FPI. In this paper we will show a new focal plane detection technique called the circle to line interferometer optical (CLIO) system. CLIO converts the circular FPI fringes into linear fringes and makes the CCD more applicable to Fabry-Perot interferometer. The design of an advanced FPI based on CLIO and modern back- thinned, AR-coated high quantum efficiency CCD operating in the MPP mode will also be presented.