Data Processing of the Middle and Upper Atmospheric Wind Retrieval Based on the Fabry-Perot Interferometer

Herein, a processing method is proposed for accurate microdisplacement measurements from a 2D Fabry–Perot (F-P) fringe pattern. The core of the processing algorithm uses the F-P interference imaging concentric ring pattern to accurately calculate the centre coordinates of the concentric ring. The influencing factors of measurement were analysed, and the basic idea of data processing was provided. In particular, the coordinate rotation by the 45-degree method (CR) was improved; consequently, the virtual pixel interval was reduced by half, and the calculation accuracy of the circle centre coordinate was improved. Experiments were conducted to analyse the influence of the subdivision and circle fitting methods. The results show that the proposed secondary coordinate rotation (SCR) by 45 degrees method can obtain higher accuracy of the centre coordinate than the CR method, and that the multichord averaging method (MCAM) is more suitable for calculation of the centre coordinate than the circular regression method (CRM). Displacement measurement experiments were performed. The results show that the standard experimental deviation of the centre of the circle is approximately 0.009 µm, and the extended uncertainty of the displacement measurement in the range of 5 mm is approximately 0.03 μm. The data processing method studied in this study can be widely used in the field of F-P interferometry.

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The O.A.O. Spectronebulagraph and the Kyoto 3D Spectrograph

International Astronomical Union Colloquium ◽

10.1017/s0252921100022946 ◽

1995 ◽

Vol 149 ◽

pp. 195-202

Author(s):

Hiroshi Ohtani

Keyword(s):

Data Processing ◽

Ccd Camera ◽

Microlens Array ◽

Local Area ◽

Observation System ◽

Atmospheric Transmission ◽

Fabry Perot ◽

Automated Observation ◽

Prototype Instrument ◽

Mode A

AbstractSpectronebulagraph, an automated observation system of tridimensional spectroscopy with a long slit spectrograph, is now in operation at the 188 cm telescope of the Okayama Astrophysical Observatory. This system is based on the local area net work of personal computers which control the telescope, the autoguider, the Cassegrain spectrograph and its CCD camera. Effects of variable atmospheric transmission during scans of target objects are removed by performing a set of two orthogonal scans and the data processing.A new spectrograph is now under development for the telescope. This instrument has multiple modes for tridimensional spectroscopy, i.e., the filter imagery mode, the imaging Fabry-Perot interferometer mode, a slit spectrograph mode for Spectronebulagraph, and the microlens array spectrograph (TIGER) mode. For the last mode, a dual preoptics to get simultaneously the sky background is introduced and achromatization of the microlenses is tried. This project is a part of development of a prototype instrument for the SUBARU telescope.

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