Ground-based airglow imaging interferometer Part 1: instrument and observation

Abstract

A ground-based airglow imaging interferometer (GBAII) is proposed to measure simultaneously the temperature and wind in the mesopause region by using airglow emissions of the O₂(0-1) band. Since it employs a wide angle Michelson interferometer with a large air gap, combined with the rotational temperature measurement, both the phase and spectral information can be obtained from the imaging results. Based on the optimization and calibrations for the optical system in the laboratory, we developed and assembled a prototype of a GBAII, and carried out one observation at the observatory of Xi'an University of Technology on 12 June 2012. The observed temperatures fall mainly on the range of 167-196 K, while both the zonal and meridional winds faintly show the feature of half-day oscillation. The consistent trends between the observation results and the standard atmospheric models suggest that the GBAII has achieved our basic design goals.

Study on the Imaging Interference of a Vortex-Light-Modulated Gaussian Beam

“…Airglow is often used as a source for passive sensing of the upper atmospheric winds. Such as WINDII [12], Waves Michelson Interferometer (WAMI) [21], GBAII [14,15] and other passive sensing instruments all use the different airglow wavelength. In previous research, GBAII also used the Gaussian profile airglow to observe the atmospheric wind, temperature, etc., parameters at the altitude of 90-100 km atmosphere.…”

“…The light field of the general Gauss profile is shown in Figure 1a, and the results of the Gauss profile vortex light are shown in Figure 1b,c. The simulated light was selected as 1 of the 12 of O 2 (0-1) airglows [14], and the wavelength was 867.7 nm. There are some novel results: The hollowing degree of image intensity increases with the increase of TC of l, i.e., the extincted part at the center increases with the increase of l shown in Figure 1b.…”

“…An optical wave with such characteristics is called 'Optical Vortices' (OVs). When our GBAII (ground-based airglow imaging interferometer) was used to capture the Gaussian profile airglow of the O 2 (0-1) band of 865.2-867.9 nm with a peak altitude of 94 km and the O ( 1 S) band of 557.7 nm with a peak altitude of 98 km over the Earth, and obtained the atmospheric wind velocity, temperature, VER, number density, and other parameters [14,15] of 90-100 km above the Earth, some vortex light characteristics were found. In the present paper, we use a LCoS to replace a mirror of the MI (Michelson interferometer) arm in the GBAII [16] system to form a GBAII-LCoS interference system.…”

Beyond the partial light intensity imager: Eliminating Moiré patterns

“…Both the PLII and PLCI use the arrangement of two key devices, the LCD and the CCD, which may randomly cause Moiré patterns. Furthermore, we employ a liquid crystal on silicon (LCoS), as there is no moving mirror for imaging system [14][15][16][17], which may also result in the Moiré patterns. We attribute these phenomena to both of the spatially discrete liquid crystal (LC) and the CCD sampling devices, which can be seen as two gratings.…”

A comparative study of three methods to detect the upper atmospheric wind speed by DASH

“…中 国科学院西安光学精密机械研究所的陈洁婧等 [10] 分析了DASH傅里叶变换法测风中窗函数的选取 对测风精度的影响, 中国科学院光电技术研究所的 彭翔等 [11] 对DSAH测风的复合光程差相移解算方 法的前提也是由傅里叶变换法从干涉图中提取位 相差. 宁通 [12] 将DASH的干涉图用傅里叶级数拟 合而提取风速, 测风精度为12.6 m/s. 所以目前从 DASH干涉条纹中提取风速有傅里叶级数法 [12] 和 流行的傅里叶变换法 [7] .…”