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A method has been developed to determine the shrinkage parameters of holographic photopolymer materials (including changes in the mean refractive index and thickness of the recording layer) during hologram recording with a measurement error acceptable for practical applications of these materials. Experimental verification of the method has proved its efficiency.

It has been shown that the problem of optimal actuator placement for adaptive square mirrors can be reduced to the analytical solution using elements of the theory of unbiased designs for the natural vibrations of a square plate with free edges. A stochastic model for the wavefront has been developed using regression analysis. Formulas are given for calculating the bias in working-out the desired optical surface geometry of an adaptive mirror.

A simple positioner, which allows one to ensure the position of a focused light beam on an object with nanometer precision and reproducibility, is proposed and studied. It can be used for positioning of focused beams (in particular, laser beams) on surfaces of optical fibers, biological objects, optical disks, thin film modulators, and holographic memory systems in the micrometer and nanometer ranges.

A simple method is proposed to determine the quality of antirelaxation coatings of the walls of vacuum optical cells containing alkali metal vapors. The method involves recording the time dependence of the fluorescence intensity of alkali atoms during exposure of the cell by resonant radiation pulses. Theory predicts that to determine the coating quality, it is sufficient to know the fluorescence decay rate and the ratio of the fluorescence intensities at the beginning and end of the pulse laser.

This paper considers a thin plane nanosystem consisting of molecular chains of dye J-aggregates forming bundles elongated in one direction and spherical gold nanoparticles located near them. Expressions are derived for the polarization of the exciton transition in the external field under the mutual influence of the dipole fields of the monomers constituting the dye J-aggregates and for the induced dipole of the nanoparticle. It is shown that in this system, mirrorless optical bistability of the fluorescence spectral density of the dye J-aggregates is possible, depending on the pump field intensity. The parameters of this dependence are critically determined by the distance between the molecular bundles and nanoparticles and by the angle between the field polarization direction and the axis of the bundle of J-aggregates. The use of the nanosystem as a sensor is discussed.

A new approach to constructing the thermal element of a multi-element array on the basis of thin pyroelectric films is developed: the element is neither thermally insulated from the substrate nor separated by a gap from the substrate surface; instead, it operates owing to accumulation of the charge generated by infrared radiation during the frame. A new principle of high-speed modulation of radiation is described. Experimental results for the behavior of the pyroelectric coefficient in barium-strontium niobate films (Ba_xSr_1-xNb₂O₆), whose values reach up to (1-2)·10^-3 C/m², are presented. It is demonstrated that the specific detectivity of sensitive elements 12 × 12 μm in size in the charge accumulation mode is greater than 10⁹ cm × Hz^0.5 ×·W^-1.

A method is proposed to shape the edges of chips in order to reduce the gap between chips in infrared-sensitive mosaic photodetectors modules. The method involves laser scribing of asymmetric grooves, splitting-off of the edge of the chip surface going under the chip, and the subsequent vertical alignment of the edges using laser radiation. The width of the gap between chips is 1-3 μm.

This paper describes the structure, operation algorithm, and circuitry of the recording channel of a multi-channel coordinate X-ray detector with a microsecond time resolution for studying the dynamics of density distribution in objects under pulsed loading. A method for fast automatic real-time control of the channel sensitivity is proposed.

The article discusses an important function, performed by mythological creativity in the modern world, - communication between different spheres of differentiated knowledge. The philosophical reconstruction of historical relation between philosophy and religion through the epoch’s mode of thought and the mythological constructions is given on the basis of research on history and philosophy of science, made in the twentieth century.

There is a belief that Kolmogorov's condition about the closeness of event probability with frequency characteristics of an event is a conclusion of Bernoulli’s theorem and that if Cournot’s principle is taken into account, the conclusion is true on any typical sampling. The article shows that this assertion is correct within the subjectivistic interpretation of the probability theory. The author proves that in the objectivistic interpretation the closeness of probability and frequencies is understood as the stability of frequencies, i.e. their grouping in a narrow field. He demonstrates that in this interpretation the frequencies stability is a precondition of an application of Bernoulli’s theorem and it depends neither on the theorem nor on the principle.