Different techniques are applied in order to obtain information about ultrafast molecular and reaction dynamics. Femtosecond time-resolved pump-probe spectroscopy is used to investigate the dissociation reaction of NAI molecules. Starting from free NaI molecules, the environment is changed to solution-like conditions adding rare gas with different pressures. Femtosecond time-resolved degenerate four-wave mixing (DFWM) spectroscopy is performed in order to investigate molecular dynamics in iodine molecules in the gas phase. Depending on the timing of the laser pulses different dynamics are reflected in the DFWM transient signal. By the use of time evolution diagrams, the varying contribution of ground and excited-state dynamics can be explained conclusively. Supersonic jet-cooled potassium dimers are investigated in their electronic ground state by a femtosecond pump-probe experiment. The ground state vibrational wave packets are created by a stimulated Raman pumping process and selectively interrogated by resonance enhanced three photon ionization.

Extrinsic and intrinsic nonlinear magneto-optics are introduced through the use of layered structures. Longitudinal magneto-optic configurations are selected to promote the maximum coupling of field components. In the extrinsic calculations, linear magneto-optic layers are deployed with varying degrees of complexity in structures that have components that can become optically nonlinear. The properties of spatial solutions are investigated theoretically using a Lagrangian variational procedure. Interesting arrangements are discussed for general polarization interaction based on a magnetic field distribution that varies both along and transversely t the propagation direction. Finally, intrinsic nonlinear magneto- optics is briefly discussed, which uses a photoinduced nonlinear Faraday effect.

Ultrathin magnetic cobalt-based Au/Co/Au trilayers have been studied by the optical second harmonic generation (SHG) and by the linear magneto-optical Kerr effect (MOKE). We show that SHG has a selective interface and surface sensitivity, whereas MOKE is bulk-sensitive. SHG was used to probe the surface plasmon resonance in Au/Co/Au films. The resonant coupling of surface plasmons with SHG, results in an enhancement and sign reversal of nonlinear magneto-optical effects. Model calculations of the observed phenomena are given on the basis of a nonlocal field theory, which permits to distinguish the different interface contributions to SHG.

The new theoretical and experimental studies of magnetochiral optical effects in anisotropic crystals in external magnetic fields and of related magneto-optical effects are reviewed. Magnetochiral effects arise when temporal and parity symmetries are simultaneously violated. The most interesting of magnetochiral effects is magneto- optical nonreciprocal linear birefringence, which is the difference of refractive indices for counterrunning eigenwaves proportional to external magnetic field. New highly sensitive methods for experimental study of nonreciprocal linear birefringence independent of optical losses in sample crystals. To measure the anisotropy of nonreceiprocal linear birefringence the two-pass optical scheme, in which the sample crystal is placed between two quarterwave plates is developed. With this scheme, the anistropy of nonreciprocal linear birefringence in LiIO₃ is measured at Ar-Kr laser lines. Also, the new accurate method for measurement of Faraday effect in anisotropic crystals in proposed, which is based on spatial segregation of eigenwaves in wedge-shaped samples. In this method, parasitic effects of natural linear anisotropy do not affect the measurements.

The application of the CARS technique with the spatial separation of the exciting and probe beams allows the elimination of the background, which appears in the signal of CARS from polaritons due to four-photon processes. The propagation length 1_p of coherently excited polaritons and the ratio of direct four-photon and two-step three- photon contributions (which are determined by rho(omega)equals(chi) ⁽³)/[(chi) ⁽²)((omega) ) ]²) to the resultant CARS signal can be determined by measuring the intensity of CARS signal, as a function of spacing between the excitation and probe regions. For A₁(z) polaritons in BeO, at frequency around 372cm^-1, we obtained the following results: l_pequals(0.3_-⁺0.05)mm and (rho) approximately equals 2.5x10².

Experimental investigations of the object image reconstruction by stimulated scatterings (SS) and SS energetical properties have been realized in this layers of different nonlinear materials in picosecond and nanosecond range as a function of thickness. Sharp SS wave intensity enhancement has been found.

Influence of relation between scattering matrix elements responsible for Stokes and anti-Stokes pulse amplification on efficiency of the energy exchange and character of self- induced amplitude-phase modulation is analyzed in the essentially transient regime.

For the first time, stimulated Raman scattering (SRS) in multimode silica fibers pumped with long XeC1 laser pulses (70 ns) has been observed. The spectral and temporal development of SRS, both experimentally and theoretically, have been studied. Two orders of SRS have been obtained in the 311 divided by 317 nm spectral region. The experimental results are in good agreement with computer simulations of SRS, in which effects of self- and cross-phase modulation and group velocity dispersion are negligible. Experimentally measured spectra of the Raman gain curve and the pump laser spectra are included in the numerical model.

Stokes field demonstrated unusually narrow-spectrum and non- Gaussian statistics for SBS in 300m single-mode optical fiber with enhanced Rayleigh losses. We show that SBS lasing takes place withing the fiber. The effect is explained by dynamic distributed feedback, due to double Rayleigh scattering of the Stokes field. Results of numerical simulation of the cooperative SBS-RS process in fiber are in agreement with experimental results.

The possibility of phase conjugation (PhC) of multifrequency radiation of a cw HF chemical laser (HF-CCL) is analyzed. The PhC is based on Bragg scattering from a spatial phase hologram, which is recorded in a resonantly absorbing medium by radiation with a frequency different from any of the conjugated signal frequencies. The mechanism of formation of a spatial phase hologram and the features of optical Bragg scattering on such structures are analyzed. The analysis indicates that the proposed system does not exhibit frequency selectivity and is basically suitable for PhC of radiation with a broad line spectrum. The choice of working components for PhC, Hbr and Xe, is analyzed at length. Numerical calculations are performed, employing a mathematical model present in this paper. The reflectivity is plotted as a function of the component concentration ratio, the intensities of waves determining the volume hologram in PhC-cell, and the angle of the laser beam's convergence. We consider the problem of cooling the medium by mixture circulation.

The phenomenon of stimulated Raman scattering (SRS) has attracted the attention of researchers by the possibility of excitation of the stimulated radiation on discreet lines in a wide spectral range. The huge number of Raman-active media are found at the present time. The most distinctive features of backward SRS were studied, both experimentally and theoretically, by M. Maier et al. The effect of transient, backward stimulated Raman scattering (BSRS) under the picosecond excitation, can be used for the generation of the ultrashort pulses with significant peak power and spectral characteristic, which are acceptable for a wide range of applications, such as spectroscopy, characterization of optical properties of the condensed media, etc. S. Arrivo et al used BSRS as a pumping source for the generation of femtosecond pulses in a short cavity dye laser. Being in the framework of a kinetic method, M. Maier et al demonstrated that forward and backward SRS propagate in considerable different conditions. The SRS pulses in the forward direction satisfy the equation of gaining saturation. The backward SRS (BSRS) pulses are amplified by the excitation radiation, moving toward the pumping pulses. The temporal profiles of SRS pulses are considerably different in both these cases. As was predicted in a work of M. Maier et al and experimentally studied by S.W. Arrivo et al, the BSRS pulses may have a duration that is significantly shorter than can be expected, based on the spectral width of spontaneous Raman scattering.

We present the experimental result of the optical diffraction observation for the light propagation perpendicular to the twist axis in the chiral Sm-C* liquid crystal. We study the polarization features of the diffracted field in the intermediate diffraction regime and present the experimental results of three-times enhancement of femtosecond second harmonic generation observation under the conditions of diffraction in the structure.

Thermo-optical distortions are considered with the account of elasto-optical effect at second-harmonic generation (SHG) for crystalline samples, which are in the form of circular cylinders and have a steady-state parabolic temperature field. For crystals ADP, LiNbO₃, and KDP, the numerical calculations for wave mismatch and efficiency of SHG with account of elasto-optical distortions are carried out.

Presented are the results of a study of resonance-enhanced third-harmonic generation and multiphoton ionization in dense zenon under excitation by the Bessel beams. Bessel beams with inclination angles from 10 degree(s) to 90 degree(s) are shown to produce ionization spectra with significant differences, as compared with the case of the ordinary Gaussian. Several features of ionization spectra are considered and discussed. Results of numerical simulation of third-harmonic generation in Bessel beams are presented and compared with experimental observations.

Cascade third-harmonic generation proves to be a versatile tool to access (chi) ⁽²) tensor components. Wherever cascade third-harmonic generation allows an interference between two second order processes, it will be able to determine ratios of tensor components. We give a full account for orthorhombic class mm2. Given is a discussion of trigonal classes. Polarization-resolved signal of cascade third-harmonic generation in LBO crystal has been recorded and analyzed.

The influence of self-and cross-phase modulation on third- harmonic generation in a hollow fiber is investigated. Analytic solutions to the coupled equations for slowly varying envelopes of the pumping pulse and the third harmonic in a gas-filled hollow fiber are derived with allowance for self- and cross-phase modulation and first- order dispersion. The possibility to control the nonlinear phase shift of the third harmonic due to cross-phase modulation is demonstrated.

It is shown that the coefficient of parametric mode interaction in the anisotropic waveguide depends on efficiency of interaction between partial waves of these modes. The dependence of the increment on frequency and the structure of field of parametric amplified modes are found for parametric amplification of the wave on the way with the pumping one for the strong pump intensity.

We have measured the temporal behavior of the phase shift induced by cascaded frequency mixing effect on femtosecond pulses. We demonstrate that the associated chirp is nonlinear and is, therefore, difficult to compensate.

Experiments on resonant four-wave mixing demonstrated high- efficiency CW down-conversion of frequency in gas (up to 25%). Meanwhile, the high intensities make the perturbation theory invalid to understand the behavior of output power measured as a function of input powers. The nonlinear susceptibility of optically thin medium is found for difference-sum scheme (omega) ₄ equals (omega) ₁ - (omega) ₂ + (omega) ₃, where fields one and three are strong and two and four are weak. In symmetric case (kappa) ₂ equals (kappa) ₄, the integral over velocity can be calculated analytically for Doppler limits in collinear geometry. The compact explicit formula obtained yields the intensity and frequency dependence. The peak of mixing coefficient as a function of intensity is found around equal Rabi frequencies of fields one and three. The effect is shown to base on resonance between two closed cycles via sublevels of dressed states. The number of peaks in a spectrum varies from three to eight. Explicit formula allows interpreting the measurements and predicting the optimal relation between parameters for high conversion efficiency in gas with large Doppler broadening.

The steady-state bright spatial solitons have been realized in a planar photorefractive strontium-barium niobate waveguide for visible light, ranging from 514.5 to 780 nm. The build-up time of the steady-state condition was about 1 s. For the wavelength of 1047 nm, the strong self-focusing of a light beam was observed. In the time scale of several tens of milliseconds the transient self-trapping of red light was observed, which corresponds to the regime of quasi-steady-state solitons. The interaction of the steady- state spatial solitons has also been demonstrated at He-Ne laser wavelengths.

New class of stable multicomponent self-consistent light field distributions is presented by the example of a problem of nonlinear wave propagation through a photorefractive crystal with drift nonlinear response. Exact analytical expressions for light field distributions of the components of such periodical solutions, which include up to three mutually incoherent light field components, have been obtained. It has been shown that such cnoidal waves are stable and their spatial structure is robust to collisions with the same cnoidal waves and to stochastic perturbations of the intensity.

An important question relevant to any technology, which utilizes the photorefractive effect concerns the response time of the photorefractive medium. For example, it is well- established that barium titanate is very slow to respond to any changes to the pump or signal beam (on the order of 0.1 - 10 a), whereas bismuth silicon oxide (BSO) is faster (on the order of ms), and gallium arsenide (GaAs) is even faster (on the order of microsecond(s) or less). Thus, any technology in which fast response is desirable would preferably utilize GaAs. On the other hand, barium titanate has demonstrated usefulness for use in such technologies as the novelty filter, in which a slow response is preferable. It is, therefore, important that the temporal response of photorefractive materials in a two-beam coupling geometry be analyzed. We have investigated the temporal response of barium titanate to sinusoidal signals, and have characterized that response as a function of oscillation frequency.

A sequence of quasi-equally spaced spectral lines, ranging from the IR to the UV was obtained, when 1.06-micrometers linearly polarized pulses of duration 30 ps and energy of up to 40 mJ were focused into a cell filled with hydrogen at pressures of up to 120 atm and formed there is a self-focusing channel. The average frequency interval between spectral lines was approximately equal to the frequency of rotational transition in hydrogen 587 cm^-1. These lines exhibited a substructure made up by components produced in hydrogen by stimulated rotational and vibrational Raman scattering and cascaded four-wave parametric processes. In the visible, the energy of each spectral line was around 10(mu) J.

We have characterized the transverse spatial dependence of the real and imaginary parts of the complex nonlinear refractive index of a semiconductor doped glass filter, which exhibits absorptive bistability. Using the Z-scan technique, combined with an interferometric measurement of the integrated optical thickness, we are able to fit the observed experimental data assuming a quadratically varying transverse temperature profile in the sample. The transverse variations in the nonlinear refractive index do not scale directly with the size of the incident beam, but exhibit marked asymmetries depending on whether the incident beam is converging or diverging.

A theoretical investigation into the dynamics of Fabry-Perot interferometer (FPI) with multilevel resonant medium has been conducted. The origin conditions and characteristics of complex dynamic operating modes of FPI have been analyzed at constant intensity of the input light beam. The mechanisms of switching from regular intensity oscillations to the chaotic ones through the sequence of period-doubling bifurcations or multiple pass Shilnikov's attractor have been demonstrated.

Pattern formation processes in passive nonlinear ring resonator were studied theoretically and numerically. The formation of not only 'classical' spatial patterns, such as roll, hexagon, and dodecagon, but more complicated flower- like patterns were analyzed. We found and described new dynamic regime in the cavity-spatial localized structure formation.

A class of models for 2-D optical systems with nonlocal transforms of spatial arguments in a feedback loop is considered. We propose applying optimal control technique and theory of distribution to controlled irreversible transforms of spatial arguments. The gradient descent method is used for the formation of localized and periodic patterns. It is proved numerically that 'optimal' transforms which produce these patterns should be of irreversible types.

A nonlinear self-action of spherically symmetric structural resonances in a homogeneous isotropic medium with a cubic nonlinearity is considered. Conditions of a self- localization of a 3-D spherically symmetric soliton are analyzed.

We have studied the effects of the external laser seeding and external mirrors on stimulated emission in powder lasers. The possibility of remove controlling of the powder laser emission has been demonstrated.

The results of theoretical analysis of multifrequency optical harmonics generation in the nonlinear crystals with regular domain structure for all types of interaction (approximately 4000 combinations) are represented. The different variants of quasiphase matching for OPO with multiple frequencies are considered.

The problem of Gaussian coherent light beam propagation in active waveguide solved by composed self-consistent model, taking into account space redistribution of gain, refractive index and heat. The transient and sin-like optical and current modulation characteristics of planar optical semiconductor amplifier obtained in quasistationary noncoherent approximation. Frequency dependent nonlinear response to the optical signal modulation is observed. The physical interpretation of the observed phenomena is given. The main parameters, which determine the device regimes are developed.

An effect of an SBS feedback mirror started by initial laser radiation is analyzed for loop and ring SBS-mirror schemes. It has been shown experimentally that the laser output power can be increased considerably by using both feedback schemes for stimulated scattering excitation as compared to SBS mirrors without feedback. The observed distinctions in the action of two lasers with these schemes are explained by different nonlinear mechanisms of SBS-amplification in these cases.

In this paper, a possibility of precise correction of phase distortions due to inhomogeneities of turbulent atmosphere at a near ground surface path 2 km long is experimentally proved. Highly efficient transmission of laser radiation pulses of 20 nsec duration with energy up to 20 J through the path with nearly diffraction limited quality is achieved.

A global cosmic system may be used for solutions to the problems of earth energy in the near future. The present paper deals with prospects for using the various gas lenses for cosmic power systems. A reflection coefficient n dependence of the inert gases from pressure is used in the gas lenses. The refractive index n of a gas is a function of pressure and temperature. The gas lenses with general diameters 5-15 m with focal distances which are equal to the cosmic orbit heights, are discussed. For the constant laser beams the lens covers can be coated with long-lasting polymeric and no fragile materials. The gas lenses without any covers can be used for the impulse laser beams. In this case a Joule-Thomson law must be taken into account. The gas lenses can be a good concurrent for thin film mirrors in some cases, which are being considered, as analyses have shown.

A broadband, tunable, scanning IR-range etlon for FEL applications was designed, developed and tested. The design details and the results of the experimental tests are described and discussed.

Experimental results of scale modeling have crossed flute cavities developed for applications in high-power free electron lasers, are described for the eight-millimeter wave range. Intense optical cavity modes were excited having ring distribution on the cavity mirrors and focused distribution in the center of the cavity between the mirrors.

Physical reasons for the development of spatial and temporal instabilities realizing in optical bistability (OB) cavity- free systems are analyzed. It is shown that there are certain types of instability. We describe diffraction instability of light beams due to its propagation through a boundary on a high absorption domain. We consider instability generated by nonlinear dependence of a relaxation time of excited states of atoms (molecules) on vibration temperature or on room temperature under the condition of presence (or absence) of nonlinear absorption. We investigate instability due to an influence of laser- induced electric field and instability caused by the delay in a scheme with additional lateral feedback and instability in a scheme with mirror having a hole at its axis caused by dynamical lenses.

Propagation and interaction of electromagnetic waves in nonuniform Bragg grating structures with space-modulated coupling coefficient and phase shifts are investigated theoretically on the base of coupled-wave model. For gratings with antisymmetically-modulated coupling coefficient the simple analytical expression for reflectivity and transmitivity are obtained. They involve the infinite set of Born approximations and are valid not only for 'shallow' gratings with (kappa) L<<1 (kappa is coupling strength, L is grating length), but also for 'deep' gratings with appaL>=1. One the base of these expressions the method for designing the shape of Bragg grating structures, which possess the required transmission spectra, is proposed. The gratings with space- modulated amplitude and phase shifts, possessing the nearly rectangular transmission spectrum, are designed with their potential application for channel separation in high-bit- rate optical fiber communication networks.

Adiabatically perturbed picosecond solitons are considered as the lock-on signal carriers being distributed through an optical fiber-sync network. Interferometric technique of measuring time intervals with the help of train-average field strength correlation functions to a subpicosecond accuracy is developed in the event of arriving the optical soliton-like pulses at a high repetition rate. Such an advantage of this technique as the ability of operating on the trains of low-power picosecond optical pulses, in particular adiabatically perturbed picosecond solitons in single-mode fibers, is revealed. Results of trial experiments with the mock-up, implemented as optical part of the sync network for a short base radiointerferometer, are present.

A pulse laser-based holographic video system combined with a multichannel AOM has several advantages and disadvantages, compared with other holographic video systems. It combines components like a multichannel AOM, a still polygon mirror and an AO deflector to eliminate a moving optical element for horizontal image scanning. The system's structure and performances are analyzed and its perspective as a future 3- D imaging media is discussed.

New (two-stage) method of writing information in 3-D optical memory devices, using second harmonic generation (SHG) of femtosecond laser pulses in thin nonlinear films, and new informative (two-component) media consisted of nonlinear optical and photochromic materials, was realized. As a result for this two-component media, the 32x increasing of writing efficiency was obtained. It was shown, that the best photochromic substances (without additional requirement for two-photon absorption cross sections) can be used in 3-D optical memory devices.

The optical system for high-speed #-D data recording in the volume media is considered. The increase of speed and density recording by more than one order is reached through the usage of: The radial deflection of the light beam on the basis of the scanner with the accompaniment of 'a traveling acousto- optical lens' Multilayer recording of microgratings and multilevel phase data coding. The heterodyne phase-sensitive method of reading. The evaluation of speed and bit density is given.

Constructive method for the formation and filtering Fraunhofer diffraction patterns and images of volumetric objects has been developed applied to 3-D measuring technologies for noncontact dimensional inspection. This method is simple, physically obvious and at the same time, sufficiently strict for engineering applications. It is based on the model of equivalent diaphragms, according to which the problem of light diffraction on volumetric bodies is reduced to the analysis of diffraction phenomena on the plane diaphragms using the Kirchhoff-Fresnel approximation. Dependencies between the characteristic parameters of the diffraction patterns and geometric dimensions of 3-D typical objects were found. Suggested efficient algorithms allow by corresponding processing of diffraction patterns to determine transverse and longitudinal sizes of extended objects with the errors 0.1 percent and 1 percent, respectively. Peculiarities of coherent optical processing the 3-D objects are investigated by the example of high- frequency filtering (contouring) of volumetric edges with perfectly absorbing and reflecting inner surfaces. Results of the investigations showed a satisfactory agreement of the theoretical and experimental data.

With the goal to establish the mechanisms of the effect we investigated spatial characteristics of the spot of laserlike radiation from the powders and the degree of coherence (DC) of this radiation. It was shown that minimum spot dimensions are 20-30micrometers (particle dimensions approximately 4-20micrometers ). The spot can change its form from one generation shot to another, as a result of particles displacement under the action of pumping pulses. The DC was evaluated using the contrast of speckle-structure. It appears that the DC is considerable lower than usual lasers with mirrors, although it has noticeable value. In some cases DC is near to its value to a dye laser. The possibility of using the laserlike effect in powders for creation of cathode screens with narrow band (approximately 0.1 nm) and short (approximately 1 ns) luminescence is discussed. Preliminary experiments were performed. As a more distant perspective, the possibility of using this effect for creation of optical memory cells is also discussed.

Construction of algebra of fuzzy numbers by Fourier holography techniques is presented. Implementation of arithmetic operations on both conventional and VSOP fuzzy numbers by both with plane reference wave and joint- transform setups is discussed. Realization of both addition and subtraction operations is presented.

The process of holographic recording in liquid photopolymer compositions (PPC), which contain a photopolymerizable component, an initiating system and a neutral component, is described in the frame of the phase separation of the original mixture performance. The value of amplitude of the refractive index modulation of holographic gratings in PPC has been studied in dependence on the thermodynamical compatibility of system polymer-neutral component, kinetic parameters of the polymerization process and the diffusion mass-transport, supported the formation of holograms. The kinetic of holographic recording in photopolymer compositions is considered in the terms of Avrami-Erofeev equation. It has been shown for composition with polymerization-diffusion mechanism of recording that it is possible to realize the conditions, at which the kinetic of recording and consequently, light-sensitivity of a material and efficiency of recording will be determined by the parameters of the polymerization process.

Associative properties of a thin quadratic off-axis hologram and a hologram of mutually conjugated waves are theoretically investigated, on the basis of phenomenological analysis of informative structure of correlation responses. Mechanisms of reconstruction of information in a system, composed of a thin linear off-axis hologram and a phase- conjugate mirror are investigated, including the mechanism of transformation of 'noise components of field into informative ones.

We continue to study the arrays of nonlinear coupled oscillators. The networks of associative memory based on limit-cycle oscillators connected via complex-valued Hermnian matrices were previously designed. Another class of networks consisting of locally connected nonlinear oscillators, closely related to so-called cellular neural networks, is the subject of study in the present paper. Within spatially continual limitations, these oscillatory networks can be considered as oscillatory media governed by the system of reaction-diffusion equations. Formation of spatio-temporal dissipative structures (wave trains, standing waves, targets and shock structures, spiral waves, stripe patterns, cluster states) in various nonlinear active media is widely used for modeling of complicated nonlinear phenomena in physics, chemistry, biology, neurophysiology. Here the results of analytical study of 1D oscillatory media corresponding to closed and unclosed chains of limit-cycle oscillators are presented. Conditions of existence of some spatio-temporal regimes inherent to nonlinear active media (diffusion instability caused by coupling, formation of wave trains and standing waves) have been clarified.

The methods are discussed of the parallel optoelectronic realization of the compositional fuzzy inference rule and the multiple-valued logic data processing scheme. Original optoelectronic design gates are proposed for MAXIMUM, MINIMUM, LITERAL logic operators, as well as for parametrical T-operators. Optoelectronic fuzzy controller set-up is being realized on the basis of these logical gates.

Influence of photorefractive effect in KD*P crystals on solid state CW and pulse laser characteristics are investigated experimentally and for the first time. It is concluded that holographic gratings change the spectral, spatial and temporal characteristics of laser radiation, which points to the novel possibilities of using KD*P crystals for control by the parameters of laser operation.

Characteristics of optical Kerr effect in spiropyran solution are investigated. Optical Kerr effect is demonstrated to be a promising technique for nondestructive data reading in 3-D optical memory systems, based on photochromic media.

Computer-generated holograms are limited by conventional lithographic fabrication capabilities, which rely on accurate deposition, exposure, and developing of photosensitive chemicals. We present alternate fabrication technologies, which use a focused laser beam to write submicron patterns by inducing changes in a metal or silicon film and LDW glass. Circular laser writing systems built at IA&E are described. This paper has reviewed some techniques and equipment for the fabrication of binary, multilevel and continuous-relief DOEs developed at IA&E.

The method is presented to get the new tert-butil-replaced polymetilen dye with a big IR absorbing at 780-810 nm. On its base, it is elaborated the thin amorphous film for optical disk memory WORM. The experiments are shown to write energy as 34 mJ/sm², signal contrast at the reading is 70 percent and the signal to noise ratio is 45dB.

Peculiarities of dynamic phase hologram recording in photorefractive media having high optical non-linearity are discussed. Shifting and deformation of Bragg angle during recording of phase holograms was observed. These effects were explained by titling and curving of the dynamic hologram during their recording and by variation of the photoinduced refractive index versus the hologram depth.

The acousto-optical (AO) methods of laser beams control in the technologies of information recording, storage, and displays are considered. The operating regimes and achieved parameters of the appropriate AO components based on paratellurite (TeO₂) crystals are analyzed. It is shown that a significant advance of the diffraction efficiency and frequency band of AO cells can be achieved by acoustic wavefront control.

The main parameters of defining the characteristics of a reflection-type holographic optical element, such as diffraction efficiency, the wavelength of the maximum reflection, spectral and angular selectivity, and grating vector directions are measured with a wide angle diverging beam incident normal to the element. Dark ring patterns in the intensity distribution of the beam transmitted through the element allow visual determination of the parameter values. The features of the rings, such as size, shape, thickness, intensity distribution and direction of deviation relative to the center of the distribution are analyzed to determine the parameter values. The results are closely matched with those predicted theoretically.

A new method of achromatic wavefront reconstruction by geometric-optical reflection of the reconstructing radiation from surfaces with constant phase difference between the object and reference waves is theoretically described and experimentally realized. Method's distinction from holographic one is discussed. Femtosecond laser pulses are used for recording in the experiment.

A version of a multi-image stereographic method is proposed and studied experimentally. Our version is relatively simple in implementation, and can be used in a wide range of applications. The synthesized 3-D image has two-dimensional motion parallax. The angular selection is performed by the lens array, combined with the flat transmission mask. A displayed object is represented in the mask as a set of arranged partial projections. The mask calculated by the special program is printed on the transparency. In the experiments, we made B/W testing stereograms that included 14 * 14 projections 64 * 64 pixels in each. Opportunities for displaying the gray-scale and color 3-D images are also discussed.

The outcomes of experimental investigations of shadow conical refraction, when the optical harmonics are generated, are represented in the paper for a biaxial crystal of lithium formiate. A technique allowing visual observation of conical refraction 'rings' is described. The contribution of different types of light wave interactions to a transformed radiation is mentioned.