Photoelectron spectra resulting from sequential or simultaneous absorption of two or three photons have been studied for ZnTe(110), ZnSe(110), and GaP(110) surfaces, with time resolution of the relaxation of carriers between the first and subsequent steps of excitation. Under 2.95 eV excitation and probing with 5.9 eV photons on ZnTe(110), we were able to follow the thermalization of conduction electrons, the subsequent trapping of electrons by surface defect states in the band gap, and the gradual relaxation toward defect states closer to the Fermi level. On GaP(110), the relaxation of photoexcited electrons and holes was studied by means of two-photon and three-photon photoelectron emission under 3.16 eV photon excitation.

Localized states manifest themselves by light absorption at the optical gap of a glass and by luminescence excited there with Stoke's shift. They are created by the minority structural motifs of one or many structural modifications in which a material can exist, and which can provide electronic states absorption at the optical gap. Their wavefunctions overlapping determine the luminescence intensity dependence on the temperature [I(T)on the order of magnitude exp(- T/T₀)] and power law (t^-1) of luminescence decay kinetics, which include intra-center processes due to triplet-singlet transitions and recombination processes due to a tunnel and overbarrier transitions, as well as a fast component of luminescence decay (some ns) due to singlet-singlet transitions.

Multiplication of electronic excitations caused by hot photoelectrons has been examined for luminescent materials on the basis of metal halides and oxides. The results of the elaboration of luminophors with a quantum yield greater than one on the excitation by Ne (16.7 eV) or He (21.2 eV) gas discharge line sources, obtained by physicists and chemists of the Institute of Physics (Tartu, Estonia), have been generalized. The possibility to reduce the near-surface energy losses by using materials with self-trapping excitons (Y₂O₃, Zn₂SiO₄, etc.) in gas discharge devices has been revealed.

The present work summarizes the results of absorption and luminescence spectra investigation of natural and synthetic magnesium aluminum spinels (MgO*nAl₂O₃) containing chromium and manganese ions. The spectra have been analyzed with an aim to determine the effect of stoichiometry 'n' on distribution of emitting ions. The Mn²⁺ is observed in both tetrahedral and octahedral coordinations providing green or orange emission. Absorption bands have been explained in terms of the Mn²⁺ configuration model. Laser excitation of chromium-comprising magnesium aluminum spinel crystals has been carried out at 7 K with the purpose to detect the nearest neighbors of Cr³⁺ ions. Luminescence emission spectra have been obtained for natural sample and three synthetic samples (MgO*nAl₂O₃, n equals 1, 2, 2.8). Decay time has been measured at different wavelengths and compared for crystals of different stoichiometry. In case n equals 2 or 2.8, computer simulation has been used to decompose smeared luminescence spectra in the 680 - 700 nm region. Gaussian curves corresponding to R- and N-lines of natural spinel spectrum have been applied as components in the calculations of nonstoichiometric spinel spectra. This suggests that there aren't normally arranged Cr-occupied octahedral positions in nonstoichiometric spinel (n equals 2.8, e.g.).

A novel high optical quality phosphate glass allowing doping with nanocrystals of CdS, CdSe, CdS_xSe_1-x solid solutions, CdTe and PbSe has been synthesized and studied. Thermal processing of the glass gives a possibility to vary both size and size distribution of the nanocrystals. High concentration of the semiconductors in the design glass provides observation of optical absorption peaks corresponding to nucleation of crystalline grains. Complicated structure of optical absorption spectra and multiple peaks related to different quantum transitions are also demonstrated for all doped glasses.

Near-to-bandgap luminescence has been studied in bulk-like CdS nanocrystals as a function of the average radii ranging above the exciton Bohr radius (from 3.3 nm to 100 nm). The surface recombination was shown to be the main recombination route under experimental conditions. Comparing the size dependences of the luminescence under high and low excitation, a striking increase in the luminescence intensity of nanocrystals with one excited electron-hole pair was discovered for average radii below 10 nm. The small-volume enhanced bimolecular recombination was shown to account for the observed data.

The specificity of mechanism of energy transport in BeO over the temperature region of self-trapped exciton transformation is considered in the framework of the model of a field fluctuation process (FFP). The paper discusses the results of the computer simulation of a perturbing effect of FPP on kinetics and parameters of thermally stimulated luminescence in comparison with the appropriate experimental data gained for beryllium oxide crystals. It was shown that the observed peculiarities of recombination processes in BeO over the temperature region between 150 and 180 K are due to the self-trapped exciton transformation.

Low temperature (T equals 5...80 K) reflection spectra at fundamental absorption edge and luminescence spectra have been measured for CsPbCl_3xBr_3(1-x) (x equals 0...1) and CsPbCl₂J crystals. Some exciton parameters were estimated. Namely, the exciton binding energy for the crystal row varies from 71 to 31 meV and the ground exciton radius does in range 10.4 - 15.7 angstrom. It was found that disordering effects were insignificant for the above mentioned solid solutions. The exciton nature change condition is not satisfied in case of halide replacing. Relaxation of the intrinsic electron excitation for the investigated crystals excited in range of fundamental absorption occurs through the following ways. It is the free and trapped exciton emission and also their scattering on LO-phonons for CsPbX₃ (X equals Cl,Br) single crystals, the trapped exciton emission for the CsPbCl_3xBr_{3(1- x}) (x equals 0...1) solid solutions and the trapped and self-trapped exciton emission for CsPbCl₂J crystals.

Radiation-induced effects in doped alkali halides, mainly in KBr:In, are studied by the luminescence technique. The activator luminescence during a 10 s under UV-light or electron irradiation and, after it, the pulsed photostimulated luminescence on a phosphorescence background were investigated. The obtained results allow us to conclude that the main host lattice excitation relevant to both the luminescence processes mentioned above is a very mobile excitonic excitation including a photon phase and the self- trapped exciton in its composition. The photon phase, as we suppose, represents a free exciton luminescence at room temperature. In this phase, via multiple reabsorption in the low-energy exciton absorption band, the excitonic excitation can overcome large distances. In the phase of the self- trapped exciton, the induced decay within a perturbed region around the activator hole center takes place. As a result, the pairs of F-type electron and activator hole centers, contributing to the photostimulated luminescence under stimulation with light in the F absorption band, are formed. The above-mentioned defect formation process is dominant over the excitation of activator ion at low activator concentration. At high activator concentration, when strong competition between reabsorption in the exciton absorption band and absorption in the local center band connected with the activator takes place, the activator luminescence prevails. The activator luminescence spectrum is found to be sensitive to the F or F-aggregate centers formation in the region near the activator hole center.

Photoreflective, photo and cathodoluminescence investigations of the electron energy levels distribution in tetragonal cadmium and zinc diphosphide crystals at 4.2, 80 and 300 K temperatures and light polarizations parallel and perpendicular to optical axis were carried out. The obtained results confirm the calculated data of the band structure of these crystals, that indicate the presence of the complicated energy spectra states and majority different type of two-quantum transitions, provides of high efficiency of non-linear processes.

Electron relaxation have been studied by means of luminescent methods in nonstoichiometric J- and Br- sodalites. The processes of 'intrinsic' electron-hole trapping were investigated at low temperatures. Electron- hole and ionic processes at elevated temperatures and the role of strong molecular coupling between halogens are discussed.

In the present work we have investigated luminescence properties of the fine, well-crystallized undoped YAG polycrystalline powders and thermochemically treated YAG polycrystalline powders. Presented work give evidence of significant role of 'antisite' defects (AD), i.e., where some portion of one type of cations (Y³⁺) occupy another cations (Al³⁺_Oh) sites and vice versa in YAG structure, on the creation and structure of luminescence centers in complex multi-component oxides.

By calibrating the photostimulated luminescence (PSL) response with the known intensity of a standard light source, efficiency of the KBr:In powder material to the x- ray bremsstrahlung exposure at room temperature is estimated. At 44 and 85 kV voltages on the x-ray tube, the values of (8 plus or minus 2) multiplied by 10⁵ and (18 plus or minus 4) multiplied by 10⁵ photons from 1 mm² area of the 1 mm thick material are obtained as PSL responses on a 1 mR x-ray exposure, respectively. Under an assumption of the uniform x-ray excitation within the material, the maximum values for the x-ray irradiation dose and the PSL response both corresponding to the upper limit of linearity range are tentatively appraised, using the data for PSL response saturation under UV-irradiation.

Performance characteristics of a doped alkali halide (KBr:In)-based imaging plate (IP) and dosemeter (D) both the devices utilizing optically stimulated luminescence (OSL) and suitable for UV-light and x-ray energy recording are described. By exploiting (silicon) photodiode array as a photodetector, the detective quantum efficiency of 0.1 for IP (KBr:In) can be achieved. A very wide dynamic range, 10¹⁰:1 for UV (6.35 eV) and 10¹¹:1 for x-ray (44 kV tube voltage) OSL recording at the spatial resolution of 1 mm², is favorable for digital imaging and considerably improves image quality. These possibilities are illustrated by presenting available information capacities, energy consumption per bit as a function of the spatial resolution, and signal contrast ratio as a function of the input energy if using the KBr:In material with optimum characteristics (the activator concentration of 10¹⁷ cm^-3, the 245 nm UV-light sensitization of UV detecting, minimum concentration of Ca⁺² ions, etc.). Both the radiation dose storage is stable only up to 18 degrees Celsius and 200 s after an x-bremsstrahlung write at this temperature. When used for dose measuring, KBr-In monocrystals can be exploited for low-intensity x-ray detection and provide a possibility of the space background measuring in a second time interval.

Spectral properties of oxygen-related defects are studied in AIN ceramics at room temperatures. Original results concerning the photoluminescence under ultraviolet irradiation are obtained; they include the excitation spectrum and irradiation dose effects. The ultraviolet light energy storage and its release under irradiation with visible or infrared light in the form of the photostimulated luminescence has been observed in AIN ceramics. The properties of the photostimulated luminescence such as creation, emission and stimulation spectra are reported. For the explanation of the experimental results the mechanism of the recombination luminescence involving the oxygen-related defect is proposed.

Intrinsic two-photon excitation and absorption processes have been studied in Al₂O₃, YAP and YAG crystals in the temperature interval 80 - 300 K. The comparison with the one-photon processes in the same region of energies of electron excitations has shown, that different electron excitations are responsible for the absorption in both these cases. Specific relaxation features of electron excitations are discussed in the frame of model taking into account non- bonding states of oxygen.

The radiation-induced electrical conductivity (RIC) of single crystals MgO, Al₂ O₃ and Gd₃Ga₅O₁₂ (GGG) has been measured during gamma-neutron irradiation at dose rates between 10² and 10⁶ Gy/h and temperature from 20 to 400 degrees Celsius. The RIC for these crystals varied in a linear manner with dose rate in temperature region 60 - 300 degrees Celsius. The activation energy of conductivity before irradiation above 230 degrees Celsius is 1.4 eV for MgO, 0.75 eV for Al₂O₃ and 0.57 eV for GGG. The activation energy decrease during irradiation and at high dose rates (greater than 10⁵ Gy/h) electrical conductivity does not depend on temperature. Single crystal MgO irradiation at 320 degrees Celsius and dose rate 500 kGy/h in electrical field 10 kV/m shows no noticeable radiation-induced electrical degradation (RIED).

This investigation is dedicated to studying of peculiarities of luminescent properties of the single crystalline films (SCF) of Al₂O₃-Y₂O₃-R₂O₃ oxide system with alpha-Al₂O₃ and garnet structure, which are used as various types of ionizing radiation luminescent detectors. These peculiarities define the number of nontrivial advantages over their volume analogues. It is shown that SCF are characterized by the low concentrations of vacancy type defects and substituent defects, and the high concentration of Pb ion as dopant. This allows us to substantially increase the spatial resolution and selectivity of cathodoluminophores on the base of these compounds.

The correlations between parameters of slow component in PbWO₄ (PWO) scintillation afterglow and presence of different traps centers has been investigated. Obtained correlations are based on the comparison of scintillation and termo stimulated luminescence (TSL) data obtained from crystals grown from the different raw materials with variation of growth conditions.

The photostimulated luminescence is studied for CsI-Tl crystal after irradiation with ultraviolet light in the 80 - 300 K temperature range. The PSL creation spectrum coincides with the D absorption band at 80 K. Three bands are observed in the stimulation spectra at 80 K: 1400, 950, and 600 nm. The 1400 and 950 nm stimulation bands are presumably explained as optical transitions in the Tl⁰ and V_k centers situated in the spatial correlated pairs. The stimulation at 600 nm band is ascribed to the unperturbed Tl⁰ centers.

The photo-induced conversion of the primary F, H center pairs into self-trapped excitons have been proposed and studied in alkali iodides.

This paper presents the results of study of the radiation stability of LiB₃O₅ (LBO) crystals with regard to optical properties. LBO crystals of the high optical quality were studied under action of an electron beam with energy of 0.2 - 10 MeV, x-rays, and polarized synchrotron radiation of a high intensity. Both the trapped electron (B²) and hole (O^-) centers were revealed and their optical manifestations were studied in detail. In particular, the strong radiation-induced optical absorption band at lambda equals 306 nm, extending up to the spectral region of the second harmonic (at about 532 nm), was attributed to the optical transitions inside the O^- center. The accumulation of defects over the dose region between 10¹⁰ and 5 multiplied by 10¹⁶ electrons per cm² was measured. The accumulation curve at 77 K exhibits two well-defined flux regions: 10¹⁰-10¹⁴ and 10¹⁴- 10¹⁶ electrons per cm². The paper discusses the origin of radiation degradation of LiB₃O₅ optical properties.

Solid state bonding of metal with oxide at room temperature have been studied. The properties of Al/SiO₂, Al/glass, Al/MgO, Mg/SiO₂, In/glass interfaces as well as to ascertain the mechanism of formation of interfaces. Structure, composition and mechanical properties were investigated using auger-spectroscopy (AES), secondary-ion mass-spectrometry (SIMS), electron microscopy and precision microindentation. The results showed marked adhesion not all over contact area but only at zones of the maximum shear stress. The effect of mechanoactivation is considered from the viewpoints of both structure formation and physico- chemical interaction of nonequilibrium systems. As a result of relaxation, formation of a narrow metal/O reaction zone spreading in the metal and being characterized by oxygen concentration gradient occurred. The reaction zone exhibits high hardness and brittleness in comparison with those of pure metals.

This paper describes computational simulations of some atomic and electronic defects in MgO and alpha-Al₂O₃, using ab initio, semi-empirical, and pair-potential methods.

The strain response of lead zirconate titanate piezoelectric multilayer actuators have been measured up to 10⁷ N/m² stress and the 3.10⁶ V/m periodic unipolar driving voltage. An additional nonstationary strain component is detected. This effect is explained in terms of a simple solution of polarization kinetics specific for unipolar driving voltage. Preliminary experimentally assertions are given for space charge effects which manifest itself in the strain as well as charge plot after removing the mechanical load. It demonstrates that the static load free equilibrium of the actuator is not complete and the charge recently supported by the piezo voltage and then trapped forms a nonuniform space charge field confining the strain relaxation.

As a first step in modeling the electronic structure of Perovskite-type ferroelectric mixed crystals K(Nb,Ta)O₃, semiempirical calculations for pure KNbO₃ and KTaO₃ are performed with the intermediate neglect of the differential overlap (INDO) quantum chemical method. The calculations are mostly done for 40-atom supercells. The choice of the INDO parameters based on the comparison of results with ab initio and experimental data is discussed. INDO results for the equilibrium geometry and the (Gamma) -TO phonon frequencies are given. The results show that the accuracy of the INDO method is sufficient for reliably reproducing the energy differences on the order of 1 mRy (per formula unit) scale which are typical when dealing with ferroelectric instabilities.

Semi-empirical method of the intermediate neglect of the differential overlap (INDO) combined with the supercell model is applied to the calculations of the F center optical properties in ferroelectric KNbO₃ perovskite crystals. It is shown that two electrons of the defect are weakly localized inside the O vacancy, unlike similar defects in ionic alkali halides, but are considerably spread over two nearest Nb atoms. For the orthorhombic phase stable at room temperatures three absorption bands are predicted to be at 2.72 eV, 3.04 eV and 3.11 eV, respectively. The first energy is close to the band at 2.7 eV observed in electron- irradiated crystals. In the high temperature, cubic phase only two bands, 2.67 eV and 3.04 eV, are expected to arise due to higher local symmetry of the defect.

The semi-empirical INDO method has been applied to the calculations of the bound hole small-radius polarons in corundum. Results for optimized atomic and electronic structure using two different approaches (molecular cluster and periodic, supercell model) are critically compared. Both models find that two-site configurations of bound hole polarons have the lowest energy (which does not exclude existence of one-site polarons also characterized by essential relaxation energies). Experimental ENDOR data on V_Mg defects are discussed in the light of the calculations.

This paper is devoted to creation of mathematical model that describes light propagation processes in arbitrary shape scintillators. Created software was used to evaluate light collection coefficient for different scintillators on the basis of PbWO₄ (PWO), Y₃AlO₁₂ (YAG) and Bi₄Ge₃O₁₂ (BGO).

The new family of ferroelectric oxides presented and some of its properties including nonlinear optical properties of LaBGeO₅ (LBGO) are considered. It is shown that these oxides have high Curie temperatures, symmetry change P3₁21 yields P3₁ and the mixed displacive and order- disorder type of the phase transitions. All second harmonic generation (SHG) tensor components are determined for LBGO crystals and the magnitude of the spontaneous polarization is evaluated from the vector part of SHG tensor as 2.4 plus or minus 0.8 (mu) C/cm². The phase transitions in PrBGeO₅ and LaBSiO₅ crystals are considered taking into account SHG data for powder samples.

Semiconductive n-BaTiO₃ film on Si single crystal (100) was studied on the electrical optical properties by solar beam and its simulator. The film was spin-coated on the Si with a buffer layer in which Pt or Ceramace G (commercial name -- SnO and Sb₂O₃ as the base materials) was employed. The electrode Pt or Ceramace G was put on the film as the top one and Ag for the lower one. The temperature for joining of the film and Si were 700, 800 and 1000 degrees Celsius. The solar beam irradiated on the film to measure the photovoltage and photocurrent and also transmittance of the film on the glass was investigated. Furthermore, the interfaces between n-BaTiO₃ film and Si were discussed by the results of electron probe microanalyzer and the microstructures were also reported.

Ion beam modified layer on x- and z-cuts of LiNbO₃ single crystal has been produced by 100 keV He ions implantation with doses from 1.10¹⁶ to 1.10¹⁷ at/cm^-2. Using ellipsometry, the complex refractive index [n-i.(lambda) .k/(4(pi) )] was measured for ordinary and extraordinary rays. The effect of ion beam modification depends on the ion beam orientation with respect to the crystal axes. Bombarding along the z-axis conserves the optical anisotropy of the material, both of the refractive index and the absorption coefficient.

Radiation of different types ((gamma) -rays, electrons, neutrons) and fluence has been used to study the defect processes as well as the change of physical parameters in PLZT X/65/35 (X equals 4.5 - 11 at.%) and PbSc_0.5Nb_0.5O₃ (PSN) ceramics and to evaluate critical irradiation conditions. Effects on optical (extinction) spectra and dielectric characteristics (polarization, thermal and frequency dependences of dielectric permittivity (epsilon) and losses), dependent on composition and state of phase and polarization have been analyzed by means of annealing in isochronic and prolonged time regimes. A gradual shift of extinction edge to longer wavelengths, reduction of polarization and (epsilon) values, and a progressive diffusion of the phase transition including a defect-stimulated phase transformation from the rhombohedral to quasicubic structure in PLZT 6.5-8.5/65/36 compositions with the increase of irradiation fluence are observed in neutron irradiated ceramics. First radiation-induced electrical conductivity studies in PLZT ceramics are presented.

Due to multifunctionality the transparent ferroelectric ceramics is attractive to solid state chemistry and physics as a promising material for active electro-optic elements. To study doping effects on the technological processing and properties, ceramic samples of Pb_1-xZ_xSc_1/2Nb_1/2O₃, have been prepared, where Z: (1) Ba (0 less than or equal to x less than or equal to 1), (2) rare-earth elements: Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu (x equals 0.1), (3) PbSc_1/2Nb_1/2O₃ doped with 5 wt.% of rare-earth oxides. Ceramic characteristics, dielectric and electro-optical parameters have been measured. Differential thermal analysis (DTA), and x-ray diffraction are used to study the influence of doping on the solid state reactions and to determine the sequence of phases formed during the processes in oxide mixtures in the 500 degree to 950 degree Celsius interval. The pervoskite structure of PbSc_1/2Nb_1/2O₃ (PSN) is found to be formed in a complicated multistage process with several intermediate products during the reaction.

The infralow frequency dielectric response of SBN single crystals with different electrical prehistory has been investigated. The data on the temporal dependencies of (epsilon) '(lgt) and (epsilon) '(lgt), and field dependencies of (epsilon) '(E) and (epsilon) '(E) after long time aging determined by dc field allow us to propose some conclusions about kinetics of the glasslike state of a material in the relaxor phase.

The surface morphology is studied by use of optical and electron microscopes with respect to production regime (rate and temperature of crystallization) of the 50 - 125 micrometer thick doped YBa₂Cu₃O₇ films obtained by Stokes sedimentation on SrTiO₃ ceramic substrate (size 20 mm by 5 mm by 0.5 mm) and firing in air or oxygen following the MTG procedure, performed in the gradient tube furnace. Evolution of thick film structure with regard to temperature and cooling rate is studied.

The influence of electron-irradiation on the dielectric properties of transparent PSN ferroelectric ceramics is studied by low (LF) and infralow (ILF) frequency spectrum analysis. Redistribution of relaxation frequencies caused by electron-irradiation has been discovered and is related to pinning impacts of the radiation-induced defects.

The possibility is demonstrated to manufacture by the recrystallization of initial powders in different molten fluxes different A2B6 powders with the qualities acceptable for monograin layer construction. Several technologies of formation of monograin layers and optoelectronic devices were developed and studied. It is shown, that insufficient electronic parameters of semiconductor sensors and solar cells designed as monograin layers are connected with the insufficient cleaning of surfaces of crystals in the monograin layer.

Significant acceleration of a photorefractive response has been obtained in a thin and long Bi₁₂TiO₂₀ waveguide-like crystals using the nonlinear self-channeling of a laser beam. Total internal reflections of strong fanning beams and their coupling with the pump beam result in the light intensity redistribution inside the crystal and in the generation of the photorefractive surface wave of high intensity, which speeds up the photorefractive response by enhancing both the beam intensity and the interaction length. The exceptionally fast photorefractive response as well as its anomalous acceleration with the increasing amplitude of ac electric field applied to the crystal were experimentally demonstrated. The photorefractive surface wave can be used as the energy source for the amplification of weak signals in two-wave mixing experiments. This fact may lead to a fabrication of fast photorefractive devices operating with low power laser-diodes.

A method has been developed to determine the temperature distribution of ferroelectric surfaces and volumes. Based on the nonlinear optical effect of second harmonic generation (SHG) in highly nonlinear ferroelectric coating, demonstration of 2D thermosensing has been performed in the wide temperature range (77 K - 600 K). Physical concept of SHG thermal imaging, design of thermosensitive coating and experimental verification of the method has been discussed.

Side-emitting optical fiber designs and main parameters have been studied. A simplified model to describe emission of the 'glowing' fiber is developed. Basic expressions for the emission parameters as functions of the input radiation intensity, distance along the fiber axis and scattering efficiency longitudinal distribution are given for several design modifications. The model assumptions have been checked experimentally by testing silica core side-glowing optical fiber samples.

The MgF₂ layers were vacuum evaporated on fused silica substrates using a crystalline and a pressed sintered evaporation materials. The transition spectra of the specimens were recorded in the wavelength range 240 - 830 nm and changes in it monitored during storage of the specimens in atmosphere. The results were analyzed using an envelope method and a fitting of Lorentzian dispersion model with various number of parameters. A rise of the computed indices of refraction and absorption during storing in the air was seen. A heating in vacuum resulted in the temporal descending of refraction and rise of absorption indices. Fitting of the dispersion equation showed a drop of the absorption index moving from 4 to 7 fitting parameters in the red side of the spectra. On the blue side (UV) both indices rose moving from 4 to 5 parameters and descended again at 7 parameters. This shows a need of proper selection of the dispersion model for describing the real coatings. The negative values for the indices of absorption obtained by envelope method displayed the inhomogeneity of the refractive index in the fresh coatings.

The method of optical surface antireflection and protection of CsJ single crystals has been elaborated. The material and methods of coating covering on the cesium iodide laser windows for IR-range of spectrum were proposed. The analysis of the reflected ray interactions from the optical surface and of the coated transparent film which have different refraction indexes shows that it is possible to change of the reflection coefficient of light from that system. The necessary material and its thickness was chosen. The sodium fluorine film with refraction index n₁ equals 1.32 was covered on the optical cesium iodide surface with refraction index n₂ equals 1.71 (the film thickness is about 20 micrometers). That's why the reflection coefficient decreased in IR-range (to 16 micrometer). Owing to this transparent of cesium iodide surface increases in that wavelength range. The microstructure of covered film and connected with its transparency and adhesion depend on covering conditions: crystal's temperature and film covering speed. The parameters of the covered coating processes are chosen. The offered methods permits us to produce monocrystalline cesium iodide windows which are transparent in visible and average IR-range of the spectrum.

The possibilities of the in situ real-time Brewster-angle interferometric reflectance probe to follow cycle-dependent film-quality changes during the atomic layer deposition (ALD) are investigated. Experiments are centered around the growth of amorphous TiO₂ thin films on fused quartz substrates in a traveling-wave reactor using TiCl₄ and H₂O as reactants. It is concluded that ALD has prospects for the preparation of microstructurally homogeneous low- optical-loss TiO₂ films in case the precise thickness control is needed. The main problem is the microporosity of the films and as a result their moderate refractive index.

In₂O₃(Sn) film CO senors in the Kretschmann configuration were investigated using a rotating analyzer spectrometer. From the experimental surface plasmon resonance (SPR) angular dependencies, applying the best fit method complex dielectric permitivity of In₂O₃(Sn) films ((epsilon) equals 2.4-i0.2) were obtained. Under exposition of sensor by CO gas at 134 degrees Celsius temperature, SPR shifted to higher angles and sufficiently broadened. Most significant change possesses an imaginary part of dielectric permitivity -- after 0.8% CO exposition it becomes 4.1, whereas a real part equals to 1.2.

The measurement results of transmission spectra through super-conducting films are given. Used were: YBCO(123) - T_c equals 77 K; BSCCO(2212) - T_c equals 80 K; TBCCO - T_c equals 87 K, in a light energy range E equals 1.4 divided by 3.2 eV and T equals 5 divided by 300 K. The YBCO transmission spectra present an anomaly at T less than 70 K, E equals 1.9 eV. All HTSC films have a maximum of the absorption band at E approximately equals 2 eV. The photochromatic effect (light-induced photo-absorption) was observed in all films. The quantity of this effect depends on the type of the sample and critical temperatures (T_c). Remnant optic radiation was detected after film light irradiation.

Here we report on the first, to our knowledge, direct experimental observation of giant thermo-optical mirror effect on the free surface of ferrofluid under He-Ne laser excitation. In our experiment a slightly focused laser beam of power in mW range is incident nearly normally to the surface, and a characteristic diffraction ring pattern has been observed in reflection mode. Concave surface deformation has been clearly observed at laser irradiated spot and has been explained in terms of lubrication theory approach for laser driven thermocapillary motion in thin layer of light absorbing fluid.

The report contains information about laboratory made radiofrequency powered electrodeless discharge sources (lamps) of resonance atomic spectra radiation for various elements (e.g. Hg, Cd, Zn, O, S, Se, Te, As, Sb, Bi, J, Br, Kr, Xe, H) having main spectral lines in UV and VUV region. There are known, and can be found a lot of new specific applications of such sources in laboratory made or commercial optical devices.

The eye movement monitor measures both vertical and horizontal eye movements by employing an optoelectronic noncontact technique with a high updates rate. The monitor is controlled by an IBM AT or compatible computer and basically consists of a sensor assembly and two cards, connected to the PC bus: an amplifier and synchronous detection unit and a 12 bit AD/DA converter. The sensor assembly is mounted to spectacle frames and connected with the computer by a flexible cable. All the measurement data are stored in the hard disk and can be represented as vertical and horizontal coordinates of the gaze at selected time moments. The monitor does not interfere with the subject's head movements nor does it obstruct significantly his view of vision. The pulsed bias and synchronous detection make the device insensitive to the background illumination artifacts.

Attenuation intensity dependences of 1064 nm and 532 nm picosecond pulses in multimode optical fibers produced for medical purposes by 'Anda' factory in Livani, Latvia are experimentally studied. A strong linear growth of inverse transmittance with intensity is found. The possible mechanism of nonlinear losses are analyzed and the conclusion is made that the observed effect is mainly due to the two-photon absorption involving defects levels. Strong attenuation intensity dependence can be used to make such fiber optical devices as light power limiters, optically driven light modulators and dynamic holographic frequency filters.