ABSTRACT
A new compact satellite spectrometer dedicated to monitoring terrestrial atmospheric ozone (ozonometer) is in preparation for the Russian Geophysics Program. Four instruments at four satellites (Ionosphere) are intended to monitor the total ozone content by measuring spectra of scattered solar radiation in nadir. The spectrometer is based on the Rowland scheme with a concave holographic diffraction grating. It covers the near UV and visible range of the spectrum, 300-500 nm, with a spectral resolution of â¼0.3 nm. At present, a qualification model has been manufactured and tested. We introduce the description of the instrument and the results of laboratory and ground-based atmospheric calibrations. The ozone amount retrieved from atmospheric measurements using the differential optical absorption spectroscopy (DOAS) method is in good agreement with that measured by the collocated Brewer spectrophotometer and ozone monitoring instrument on board the Aura satellite.
ABSTRACT
The investigation of a nonreciprocal effect for the example of collinear acousto-optic interaction is presented. It is shown that this effect influences the parameters of diffraction and the operation of modern acousto-optic devices, particularly acousto-optic tunable filters (AOTFs), at the frequencies of ultrasound of about 1 GHz and higher. The analytical expressions are obtained, and the calculations of the nonreciprocal effect for different acousto-optic materials are carried out. The effect is registered experimentally at the optic wavelengths of 633 and 532 with the help of a collinear AOTF on the base of a lithium niobate crystal.
