This article is devoted to the issues of remote sensing of natural surfaces in order to determine their temperatures by their own radiation in the infrared (IR) region of the spectrum. The basics of the radiometric method are briefly described, the factors influencing the result of remote measurements are analyzed. A formula is obtained by which the influence of ambient radiation (background) reflected from the studied surface on the result of thermodynamic temperature measurement is calculated. The calculation takes into account the emissivity of the reference black body, according to which the IR radiometer was calibrated, the background radiation temperature during calibration of the device and is performed for two spectral ranges located in the transparency window of the atmosphere. The calculation results are relevant for improving the accuracy of remote sensing of temperature fields of natural objects.

Keywords: remote sensing, IR radiation, IR radiometer, temperature field, energy brightness, background radiation, blackbody, optical flux, radiation temperature, emissivity

In this paper, we propose the option of constructing a multi-channel system of quantum key distribution with frequency coding, based on an electro-optical scheme of a system of quantum key distribution (hereinafter QKD) with pairs of amplitude modulator and phase modulator on the Alice side, and pairs of phase modulator and amplitude modulator on the Bob side ( hereinafter referred to as AMPM-PMAM), using a Comb generator, a multiplexer and a demultiplexer to form multiple parallel quantum subchannels.

Keywords: quantum cryptography, quantum key distribution; frequency coding, electro-optical photon modulation, amplitude-phase tandem modulation

In this paper, we propose a method for expanding the functional range of image pre-processing systems (LUTs) and increasing sensitivity by reducing processing time. The main advantage of the implementation of preprocessing at FPSS is the implementation of spatio-temporal discrete-analog processing simultaneously with image formation. A disadvantage of the known methods for implementing image pre-processing systems is the low performance of the LDPE due to the fact that the processing is carried out step by step and the number of cycles is always the maximum regardless of the observation conditions. The purpose of the work is to expand the functional range of software and increase sensitivity, by reducing processing time. This goal was achieved by combining processing for the symmetric coefficients of the impulse response of a non-recursive filter. To assess the possibilities of improving the speed of the proposed processing method, noise suppression modeling on an X-ray image was simulated using low-pass filters with masks of size,,. Based on the difference between the original and processed images, it was concluded that the use of a mask is advisable. The use of a new processing method with a mask of dimension will allow to increase the performance by 2.778 times and, accordingly, the sensitivity of the software with 1.339 times.

Keywords: pre-processing, spatio-temporal, images, charge-coupled photosensitive devices, non-recursive filter

The paper presents an approach to the complex measurement of temperatureand mechanical strain for . Using a polyharmonic signal of a given shape allowed two sensors to be simultaneously polled. Temperature and mechanical strain sensors are made in the form of fiber Bragg gratings with special spectral characteristics.

Keywords: Bragg fiber grating, sensor, mechanical strain temperature, construction, photodetector, polyharmonic method, optical fiber, special form of the spectrum, light

An optical sensor for measuring small displacements and rotation angles is described. Based on a non-contact principle of operation, which can be used to control small movements in installations to determine internal friction by the type of torsion pendulum. The main characteristics of the device are shown and the installation and connection diagram is shown by means of the ADC to the computer

Keywords: optical sensor, angle of rotation, displacement, internal friction, microcontroller, torsional pendulum, photoresistor, signal filtering, signal transmission, non-contact, ADC

The article presents the implementation results of the methods of linear contrasting, image histogram equalization, adaptive histogram equalization (AHE) and contrast limited adaptive histogram equalization (CLAHE) as test software for thermal image processing. It also proposes some ways of enhancement of the CLAHE method that eliminate the necessity to manually select the parameters to be changed.

Keywords: image processing, computer processing, histogram processing, histogram equalization

Development of technical lighting capabilities maked it possible for lighting designers to implement any ideas. Although the structure of the human eye as a biological receiver of radiation is still the same despite lighting equipment progression. Many urban lighting design solutions implemented in various cities all over the world leads to promptly considering the issue of lighting quality assessment. A comprehensive study of an urban environment supported by town planning analysis allows to draw conclusions about the rationality of expended energy resources and the quality of realized objects. The relevance of luminance distribution analysis in a night city environment increases every year, especially for cities with lighting strategies aimed at a quantitative increasing of illuminated objects without hierarchy of priorities. By the example of the central part of Tula city an integrated approach to the analysis of evening image of the city has been considered, the luminance ratios were estimated for the facades located on 11 central city streets. This quantitative luminance levels analysis allows to draw objectively conclusions about the quality of existing light environment of the city and to understand possible steps for its further development in a new way.

Keywords: urban lighting, lighting environment, architectural lighting, luminance distribution, luminance measurements, qualitative analysis

The paper considers an optical laser-free system for express analysis of vibration state, which includes a dedicated backlight and a videocamera of vision system, which is a displacement sensor. The problem of determining the degree of mutual influence of the reflecting properties of the surface and the spectral composition of the radiation of the light source on the noise level of the CCD matrix is ​​solved. Using dispersion analysis of the results of a field experiment, it was determined that the spectral composition of the backlight is the most significant factor; the best combinations of parameters were identified. Comparison of the noise level with the real vibration signal showed the crucial role of the selection of combinations of the backlight and the type of the reflecting surface.

Keywords: noise CCD, dispersion analysis, vision system, vibration control, optical measurement, reflective properties, spectral composition, backlight, vibration

The paper describes the implementation of a fiber-optic single-channel vibration sensor built on the basis of two fiber Bragg gratings, a broadband source, a photodetector and a sound card of a computer used as an ADC

Keywords: vibration, fiber optic sensor, fiber Bragg grating, Fourier transform

The paper presents an approach to the complex measurement of temperature, humidity and electric arc for shields of complete switchgears. Using a polyharmonic signal of a given shape allowed two sensors to be simultaneously polled. Temperature and humidity sensors are made in the form of fiber Bragg gratings with special spectral characteristics.

Keywords: Bragg fiber grating, sensor, humidity, temperature, electric arc, complete cabinet, power distribution system, optical fiber, lens, light

Radio-photon sensor systems represent a wide range of measurement information systems that use today's standardized parallel and sequential type optical analog chains with filtering, which allows to functionally display information received in the optical range in the radio frequency. One of the main, most widely used elements in the RPSS, which solves the problems of forming, filtering and measuring the conversion of optical radiation, including for the stage of further generation of radio-frequency carriers, is the fiber Bragg grating. The cumulative analysis made it possible to propose for the design of RFSSS a new class of sensors - address fiber Bragg structures (AFBS) constructed on the basis of FBG with two symmetrical discrete phase shifts or two identical FBGs potentially having improved metrological and technical and economic characteristics, as well as enhanced functionality compared with existing, widely used resonance sensors, based on the effects of Bragg and Fabry-Perot in fiber optics. AFBS, by its designation, should become a multifunctional element of the RPSS that act as sensors, formers of two-frequency optical radiation, the basis for generating in each of them a unique difference radio frequency carrying measurement information, which is also the address for their multiplexing. This made it possible to propose a new, separate class of the RPSS, which was named "Radiophotonic sensor systems on adressed fiber Bragg structures", the hierarchical classifier for the creation of which was the main subject of this article.

Keywords: radio-photon sensor system, addressed fiber Bragg structure, integrated fiber-optic sensor, interrogation, multiplexing, hierarchical classifier of construction problems, system approach

The article deals with the theoretical substantiation and computer modeling of an optical vector spectrum analyzer based on asymmetric optical two-band modulation using a parallel two-channel Maha-Zehnder modulator. The proposed method and device make it possible to achieve twice the measurement range in comparison with the classical optical vector analyzer based on single-band modulation and to realize a simpler and more reliable configuration in comparison with the previously presented amplitude asymmetric optical vector analyzer with two sidebands. It can be possible to measure the frequency characteristics of a fiber Bragg grating with a width of up to 0.5 nm (60 GHz) with a resolution of up to 1 MHz (about 5-10 fm) using electrooptical modulators with a bandwidth of up to 30 GHz.

Keywords: optical spectrum analyzer, two-frequency modulation, frequency asymmetry, measurement range, fiber Bragg grating

The article considers a method of increasing the resolution of images in holographic systems based on subpixel shift algorithms. Methods of solving systems of equations of large dimension by reducing to block form are considered. The simplest solution is obtained when a set of matrices with an increased resolution is formed from a set of matrices with a shift in one direction, and then the resultant matrix is formed from the resulting set.

Keywords: super resolution, subpixel shift, holography, solution of systems of equations, holographic interferometry, aperture

Modern distributed temperature control systems are used today everywhere, in particular, in the telemetry of oil and gas wells. Thus, when creating a distributed fiber-optic temperature sensor based on Raman scattering (DTS) for these purposes, the problem of improving its metrological characteristics always remains urgent. They are in turn determined by the known SNR (signal-to-noise ratio, SNR from English Signal-to-Noise Ratio). To achieve this goal, it is proposed to use a promising method of increasing the SNR in the DTS based on encoding the probing sensor signal by the Hadamard code sequences (simplex coding). For this purpose, a numerical experiment is carried out to implement this coding method using the DTS model and taking into account the noise of the photodetector device. The article presents the simulation results, confirms the effectiveness of the coding method, and summarizes the results of the simulation.

Keywords: distributed fiber optic temperature sensor, Raman scattering, photodetector device, noise, signal-to-noise ratio, optical pulse encoding, Hadamard code, simplex coding

The multi-advantageous fiber Bragg gratings (FBG) have attracted considerable interest from developers of various optical systems, including communication systems with spectral and code multiplexing, as well as fiber-optic and radio-photon sensor systems. The complexity and high cost of multiplexing and interrogation of complex fiber-optic sensors (CFOS) is still the main limitation for the widespread introduction of sensory systems, both distributed and quasi-distributed, and point-type.This article proposes a new multiplexing method that takes advantage of both broadband fiber-optic and dual-frequency or polyharmonic radio-photon sensor systems. The simplest broadband radiator is taken from the first, but a complex and expensive system of spectrometry is not used to determine the central wavelength of the FBG. From the second, a recording system is used at the beat frequency between two components, but an expensive system for generating two- or polyharmonic sounding systems is not used. The multiplexing parameter is determined by the frequency of separation between two identical over-narrow-band FBGs, which differs by a certain amount from each of the CFOS and, in fact, generates its address. At the same time, FBG-based structures remain a sensitive element of the systems. Thus, a new class of sensitive elements is formed - address fiber Bragg structures (AFBS).

Keywords: radio-photon sensor system, address fiber Bragg structure, integrated fiber-optic sensor, interrogation, multiplexing, two identical over-narrow-band fiber Bragg gratings, frequency spacing, address

In this paper, it is shown that the noise of the photodetector device (PD) is the dominant factor limiting the metrological characteristics in real distributed fiber-optic temperature sensors based on Raman scattering (RDTS), which contribute significantly to the process of signal noise using the example of the RDTS taking into account the noise of the PD, which was chosen as the avalanche photodiode (APD). The analysis of the main types of noise in the model of an APD in the model, including both basic PD noise, and characteristic for APDs, for example, their influence on the signal-to-noise ratio (SNR). The graphs of the dependence of the influence of noise on the RDTS, derived from the SNR ratio, are given and conclusions are drawn about the predominance of some noise over others under different conditions, based on their.

Keywords: distributed fiber optic temperature sensor, avalanche photodiode, shot noise, dark noise, thermal noise, amplitude noise, signal-noise ratio, random number distribution law

In this paper proposed a statistical model of the optoacoustic transformation in the moving liquid medium using nanoparticles for a noninvasive blood analysis system. Since to increase the accuracy of measurements should take into account the probabilistic nature of the distribution of nanoscale objects as contrast agents in the blood stream in the human cardiovascular system. To determine the statistical characteristics of the component of the sound signal formed by a conglomerate of nanoscale objects using Monte Carlo simulation. Main static characteristics were calculated and the density distribution of the probability of the normalized amplitude of the sound signal was determined for a series of numerical experiments.

Keywords: optoacoustics, optoacoustic effect, flow cytometry, acoustic signal, carbon nanotubes, laser sound excitation, statistical analysis

The analysis of a two-dimensional scanner lens based on a triple lens system for a laser with a wavelength of 1.06 μm is performed. The first chapter indicates the scope and features of f-theta lenses. In the second chapter the initial conditions for the design of f-theta lens are given. In the third part, the simulation results, showing the parameters and efficiency of the system for 2 types of construction are given. The parameters and efficiency of the system are demonstrated. For each system, the optimal parameters are calculated, and the technical criteria for the possible application are outlined. The geometrical characteristics of the systems are shown, lens materials are described. A variant with a distortion of 0.0035% with a maximum focal spot of 24.9 μm was obtained.

Keywords: scanning system, f-theta lens, optical design, laser engraving, galvo

The manuscript describes the design of a simple LED illuminator for fluorescence microscopy of biological objects. As the light source, high-brightness semiconductor diodes were chosen that provide stable low-noise light. This distinguishes them from traditional light sources, such as mercury lamps. The presented light source can be used to record low-amplitude fluorescent signals in studies of excitable cells performed using calcium or potential-sensitive dyes. The illuminator is made of inexpensive, easily accessible components.

Keywords: high-brightness LEDs, illuminator, fluorescence, microscopy

In optical-electronic systems (OES) of visual observation, the non-uniformity of the output signal is compensated quite well. At the same time, the non-uniformity of the sensitivity of the photodetector (NUSP) degrades the threshold sensitivity of the photodetector devices. At the same time, compensation does not lead to an increase in the characteristics of the OES. Thus, assessing the impact of NUSP on the characteristics of detection of the OES is an urgent task. The calculation of the estimation of the mathematical expectation of the signal shows that it is biased and the displacement is proportional to the sensitivity of the corresponding element. Compensation for NUSP eliminates this bias, but the effectiveness of the assessment changes and the NUSP is transferred from the mathematical expectation to the variance. The presence of NUSP results in a corresponding the non-uniformity of the probability of correct detection and a threshold signal. Performing compensation does not change the probability of correct detection and the threshold signal. It is shown that for each element of the photodetector the detection range is determined by its sensitivity. The ratio of the maximum range to the minimum is related to the ratio of the maximum sensitivity of the photodetector element to the minimum. The presence of NUSP leads to a corresponding uneven detection range. It is shown that the compensation of NUSP does not change the value of the detection limit. At NUSP of 40%, the minimum detection range will be 1.5 times less than the maximum detection range.

Keywords: optoelectronic system, non-uniformity of sensitivity of the detector, detection range

A variant of the solution of the problem of characterization of a resonant Fano contour in optical biosensors of refractometric type based on ring fiber Bragg gratings with pi-shift is presented. The use of biosensors of this type makes it possible to increase the sensitivity of detecting changes in the refractive index of the medium under investigation to the level (1-2) x10-9 RIU. These sensitivity values are achieved due to the formation in the lattice of a high-quality Fano resonance with a loop width at half-height equal to 1-5 pm. However, the possibility of obtaining a significant gain in metrological characteristics on the one hand, poses the problem of characterizing such narrow-band resonances on the other, since the existing optical spectrum analyzers do not have the appropriate resolution. To solve this problem, we propose a radio-photon method of three-frequency probing of a high-band and an asymmetric Fano contour by symmetric amplitude-modulated radiation with side-amplitude components unbalanced in amplitude. In contrast to the previously used for solving similar problems of two-frequency symmetric sounding with equal amplitudes of side components and a suppressed carrier, we have uniquely determined the central frequency, the maximum amplitude and Q of the Fano circuits, as well as the possibility of greatly simplifying the technique of collecting information on their parameters. The article consists of two parts, which consistently reflect the posing of modeling problems and discussing its results with confirmation of the results of physical experiments.

Keywords: optical biosensor, refractometry, Bragg fiber grating, phase pi-shift, Bragg annular fiber grating with phase pi-shift, Fano resonance, refractive index change, sensitivity, resolving power, radiophoton measurement methods, two-frequency symmetric balance

A variant of the solution of the problem of characterization of a resonant Fano contour in optical biosensors of refractometric type based on ring fiber Bragg gratings with pi-shift is presented. To solve this problem, the first part of the article proposes a radio-photon method of three-frequency probing of the upper-band and asymmetric Fano contours by symmetric amplitude-modulated radiation with amplitude components unbalanced in amplitude. To characterize the central wavelength, a functional analogous to the modulation coefficient of the beat envelope between the components of the probing radiation is introduced. The requirements for the selection of the frequencies of the side components at which the uniqueness of the functional is preserved and the maximum sensitivity in the measurement range determined by the bandwidth of the Fano contour at half-height are justified. The possibility of extending the range of lateral frequencies and increasing the sensitivity of measurements with the use of two-frequency sounding with a frequency reduced by half and amplitude unbalanced side components with a suppressed carrier is shown. An example is given of a comparison with the two-frequency symmetric probing, previously used by us for solving similar problems, with equal amps of side components and a suppressed carrier. Based on the results of characterizing the Fano contour with fixed probing, it is possible to unambiguously determine the central frequency, the maximum amplitude, and its Q-factor.

Keywords: optical biosensor, refractometry, Bragg fiber grating, phase pi-shift, Bragg annular fiber grating with phase pi-shift, Fano resonance, radio-photon measurement methods, amplitude-balanced three-frequency symmetric probing, two-frequency disbalanced and a

The new polarization integrated-optic scheme based on weak-guided waveguide in glass is proposed - the passive 90-degree convertor of linear polarization. The converter has the evoulution type of it working principle. Converter consists of four-layer waveguide, which includes ion-exchange waveguide in glass with high-index cladding film, having tapered thickness or (in another variant of converter) tapered width. The working principle of converter has been explained with mode analysis techniques. The calculations showed that in the small range of thickness (or width) of nano-scaled cladding film the second and third waveguide modes have nearly equal effective indices and hybrid structure of fields, and out of this range the same modes have the field structure of modes TM0 and TE1. The smooth (adiabatic) increase of waveguide cladding film thickness (or width) along it longitudional geometric axis means that such waveguide is a polarization converter, which transforms mode TM0 to mode TE1.

Keywords: Integrated optics, polarization converter, optical waveguide, guided-wave mode

An overview of the basic schemes, characteristics, and directions of development of microwave photonics systems is presented in this paper in terms of requirements defining the parameters of external amplitude-phase modulation of laser radiation as a key process for the formation of radio frequency signals in the optical range for systems with polarization multiplexing of polyharmonic signals.

Keywords: microwave photonics; external amplitude and phase modulation, optical generation of radio frequency signals; generation of poly-harmonic optical signals with microwave frequency components

microwave photonics; external amplitude and phase modulation, optical generation of radio frequency signals; generation of poly-harmonic optical signals with microwave frequency components

Keywords: microwave photonics; external amplitude and phase modulation, optical generation of radio frequency signals; generation of poly-harmonic optical signals with microwave frequency components