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AbstractA new method of laser-thermal imaging spectroscopy is presented and the results of studying samples with different absorption coefficients are reported. The times required for heating the surface of these samples by laser radiation with a wavelength of 0.634 µm to a temperature exceeding the initial value by 0.3°C are calculated and compared with the experimental data. The depths of laser-radiation penetration into the surface layer of the material under the condition of external and internal reflection are calculated. The depth determines the transition region in which the energy of absorbed laser radiation transforms into the thermal energy of the substance. It is shown that the method allows the surface of materials to be studied and zones with different optical and physical-chemical properties to be studied. The method can be used to solve problems in the field of medicine, surface restoration, forensic examination and others.

The metrological characteristics of an automated interferometric system for measuring the surface shape of diffusely reflecting objects have been experimentally studied. Changes in the amplitude of the output signal during modulation of the optical path difference were studied and visualization of the effect of introduced interference on the measurement error was made. It is established that as the angle of incidence of optical radiation increases, the duration of the interference signal increases and, correspondingly, the measurement error of the automated interferometric system. The dependence of the measurement range on the scanning frequency of the reference mirror is obtained. The measurement error of an automated interferometric system under normal illumination does not exceed 0.67 μm.

The paper presents the possibility of using an optoelectronic computer system as an optical scanner. Subsurface layers of human skin were scanned in vivo at different depths of light penetration. The obtained results showed detection of a foreign body (metal shavings) in subsurface skin layers of the elbow joint.

The metrological parameters of a phase-monitoring system were studied. The ability of this system for monitoring the state of biological objects (dental tissue) was demonstrated. The shift vector was used to test the accuracy of the specklegram processing method. Dental tissue under load was experimentally studied. Projections of the shift vector in loaded dental tissue along OX and OY were measured.

A limited-coherence interferometer system for examination of biological materials has been developed. The microrelief profile of human skin was probed in vivo. It was found that the limited-coherence interferometer system can be used as an optical tomograph. Oil penetration into wrist skin subsurface layer was measured using this system.

Results are presented of experimental spectropolarimetric investigations of multimode fiber-optic waveguides with core diameters between 65 and 404 μm in the infrared (0.8, 1.3, and 1.55 μm). A theoretical explanation is proposed for the results.

The paper deals with the application of spectrophotometric method and the sensor for determination of contaminating hydrocarbon impurity presence in waste water. The sensor is designed on the basis of modern element base. For measurement accuracy increase it has computer processing of analysis results for the absorption spectra of liquid (water) media in the ultraviolet wavelength range. The proposed sensor and computer program enabled the study of hydrocarbon impurity presence in the water that is an important factor for continuous monitoring of the environment. The absorption spectra of gasoline, diesel fuel, synthetic motor oil, fuel oil, natural oil are given as the most frequently present as impurities in the water, measured on an automated spectrophotometric sensor model. The use of modern small-sized elements makes it possible to design a small-sized highly sensitive sensor for express analysis of the water quality.

The paper considers the possibility of a flat light field creation (light raster) of a large size by laser scanning at a distance of several tens of meters with angular sizes equal to 20º×4º. It is shown that the filling of such size raster by light is possible with the use of a single laser. The uniformity of light raster illumination is achieved by choice of parameters for collimating and scanning optical systems, the speed of light spot movement on the line and frame, turnover frequency of frames, spot light overlap factor. We present findings that give the possibility to obtain relatively uniform raster illumination at laser scanning and the filling of large size raster with low power laser light from the radiation source.

Subject of Research.We propose a solution for amber identification problem (succinite) as an example of natural polymeric material of organic origin. The solution is based on obtaining its infrared absorption spectra by infrared spectroscopy. The advanced method makes it possible to obtain both real and elemental compositions. In the conditions of growing demand for the use of such composite (complexly composed) materials on an industrial scale and the lack of existing methods for determination of their composition, the proposed method can become a new solution to the identification problem. Method. The basis of the proposed method for succinite study by infrared spectroscopy is transmission spectroscopy with the measurement of specular and diffuse reflection. We used the infrared Fourier spectrometer VERTEX 70 (BRUKER), the RockSolid ™ interferometer with the HYPERION 1000V microscope for the study. Amber samples from the Palmniken deposit, obtained in the city of Kaliningrad, Russian Federation, were used as the researched objects. Samples of various degrees of transparency and heat treatment were selected. Main Results. We have obtained and comparedthe data of infrared succinite spectra by the proposed infrared spectroscopy method. The distinctive characteristics are shown in the four main spectra groups: 1700–1735 cm–1, 1640 cm–1, 2800–3000 cm–1, 3400–3480 cm–1, regardless of material transparency characteristics. Five main links on the obtained IR spectra have been experimentally identified, which can be used as characteristic features for the identification and diagnosis of the succinite from the Palmniken deposit in terms of material composition. The influence of amber thermal processing on the differentiation of its structure, in particular, the restructuring of the C-O group makes it difficult to identify in heat-treated materials and requires further investigation of this phenomenon. Practical Relevance. The proposed method may be of interest in the field of the theory of knowledge of materials science, research related to identification processes, processing and manufacturing of products from amber. The carried out studies can find application at synthesis of high-molecular compounds, in issues connected with the development and distribution of various cases of application of organic nature materials, succinite, in particular.

The paper deals with the application of spectrophotometric method and the sensor for determination of contaminating hydrocarbon impurity presence in waste water. The sensor is designed on the basis of modern element base. For measurement accuracy increase it has computer processing of analysis results for the absorption spectra of liquid (water) media in the ultraviolet wavelength range. The proposed sensor and computer program enabled the study of hydrocarbon impurity presence in the water that is an important factor for continuous monitoring of the environment. The absorption spectra of gasoline, diesel fuel, synthetic motor oil, fuel oil, natural oil are given as the most frequently present as impurities in the water, measured on an automated spectrophotometric sensor model. The use of modern small-sized elements makes it possible to design a small-sized highly sensitive sensor for express analysis of the water quality.