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Results of investigating dynamics of a precision frequency divider by 3 based on a selfphase-locked doubly resonant optical parametric oscillator and triply resonant oscillator are described. It is shown that in the two cases, manifestations of self-phase locking are a dip of intensity and resonator eigenmode broadening.

A laser Doppler tomography method is proposed for investigating scattering noises, shrinkage, modulation amplitudes of refractive index and absorption coefficient, and other characteristics of volume or thick recording media. The method is based on acoustooptical scanning of a test volume grating recorded earlier in the medium and on layer-by-layer collinear heterodyne detection of the scattered field. The optoelectronic scheme of the system intended for experimental validation of the method is considered. Formulas for estimating the spatial resolution of the method, the optimal test grating period, the maximal number of detected layers are obtained. Their dependence on the optical system grating parameters is shown. An example is reconstructed values of the amplitude and phase of scattered light in deep layers of a volume grating written in a photopolymer 130 m thick.

Distortions of reconstructed data page images in a holographic memory under the Bragg deviation effect are experimentally investigated and modeled. It is found that not only the diffraction efficiency of the reconstructed image is reduced, but also the intensity distribution of information elements over the image field is nonuniform. For inhomogeneous volume holograms, distortions of the reconstructed data page image are more complex. As a result of blurring contour of the angular selectivity characteristic, the level of mutual interferences of neighboring holograms grows, but the intensity nonuniformity of information elements over the data page image field decreases.

A modified integer interferometry method is proposed for eliminating the interference fringe profile distortions caused by errors in interferogram recording and processing.

The profile is calculated for photogenerated nonequilibrium electron concentration in thickness of a three-layer film -MCT structure in crossed electric and magnetic fields, in which the band gap of the central region is constant, but increases in adjacent variband regions. It is shown that a three-layer structure with variband regions can be replaced by a homogeneous film via introducing effective surface generation and surface recombination velocities at boundaries of central and variband regions.

A gradient autonomous object movement control algorithm is proposed. The algorithm ensures search and tracing of a scalar field isoline for a vehicle with one sensor. A substantial limitation is the possibility of obtaining only local gradient estimates at discrete times. The algorithm is based on input of an additional test signal to the control system. This enables the vehicle with one sensor to calculate the total gradient value.

Principles of conversion of single time intervals into a digital code with the use of interpolation of the reference period for reducing the sampling error are reviewed. Interpolating converters are based on integrated digital delay lines and phase interpolation elements, which allow the resolution lower than the propagation delay of a single logical gate to be reached.

A non-quadratic regularization algorithm modification is proposed. It ensures identifying and filtering angular spectrum false components by choosing regularizing functional parameters. The algorithm efficiency was proved by modeling while solving the problem of multibeam wavefield division using one input data realization.

Amplitude-phase representation of spatial group point objects given as quaternion signals is considered. The problem of estimating the rotation parameters and sequencing the point marks incorporated in a group object is solved. The obtained results allow using the matched filtering algorithm to solve the problem of recognizing spatial group point objects with unknown parameters of rotation and numbering of points in the object.

Methods for estimating the integral characteristics of electron microscope image periodograms, based on Hartley transform, Q-transform, and cosine transform, are proposed. It is shown that the cosine transform is more appropriate for filtering and improvement of psychophysical image perception on its basis. Various approaches to implementing matched filtering via cosine transform are considered. A procedure of electron microscope image decomposition with the use of various orthogonal transforms and filters based on Fourier patterns of Gauss and Morle wavelets is proposed and studied. It is shown that electron microscope image structure analysis using scalograms of orthogonal image transforms is promising