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 ∼0.3  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.

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.

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Modern acousto-optic (AO) tunable filters have reached the values of spectral resolution exceeding 104 and operate with acoustic frequencies up to a few gigahertzes. At such high frequencies and such narrow bandwidths, there appear effects so far neglected. Among them there is non-reciprocity of AO interaction. It consists in the fact that acoustic frequency of light diffraction by ultrasound is different when optic beams propagate in directions opposite to each other. In the present research, the new effect has been studied theoretically and experimentally for the example of collinear AO diffraction. Theoretical analysis and calculations related to particular AO materials have shown that the effect is essential at acoustic frequencies about 1 GHz and higher. The value of the non-reciprocal shift of acoustic frequency can be as high as the frequency bandwidth of the filter. The effect has also been registered and investigated experimentally in a sample of lithium niobate crystal. The experimental data has totally confirmed the theoretical analysis. Therefore, it has been proved that the non-reciprocal effect influences the parameters of AO diffraction and, consequently, operation of AO filters at high frequencies. On the other hand, one can design devices, e.g. directional couples, exactly based on the non-reciprocity.