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Focusing Fresnel lenses are used in many fields of applied optics. These devices are used in optical sensor systems for imaging and optoelectronic integration. The traditional Fresnel lens concentrates the light intensity on the center of the formed image. We present a microprismatic Fresnel lens that transforms a circular incident parallel light beam into a homogeneous light circle with the necessary diameter at a certain distance from the lens. These transforming Fresnel concentrators can be successfully used, for example, in monitoring devices to automatically adjust the output signal from four-quadrant photodetectors. Traditional focusing Fresnel structures are manufactured by photolithographic methods or adjustable direct laser recording with photoresists. These methods enable the formation of stepped optical structures, which have inherent surface defects, resulting in the formation of images that are not high in quality. The proposed specialized Fresnel concentrators can be easily fabricated via the diamond cutting method, which enables the manufacturing of flat working surfaces with exceedingly high optical quality. We also develop a method for simulating the Fresnel transforming lenses with flat conical working facets and calculate the geometric parameters of the circular concentrators. We then apply the simulation results to the diamond cutting method and fabricate the microprismatic light transforming lens samples. These samples are then investigated experimentally with a collimated laser beam. The obtained data agree with the theoretical predictions.

Now, in many fields of applied optics, the focusing Fresnel lenses are used. Mostly, such devices are created for tracking different objects; they are used also for forming the precise visual images, even with a changing focal distance, for solar concentrators, and for many other applications. Different methods have been proposed for designing such optics. The flat focusing Fresnel structures were manufactured by the photolithography methods or by the adjustable direct laser recording with photoresists. Such methods allow the formation of known stepped structures [10–15] but the optical quality of images obtained with such aspherical surfaces is not very good. The high-quality images are not practically realized due to the defects of created aspherical surfacesHowever, for some light signal processing systems it is necessary to convert a parallel circular light beam into a uniformly illuminated light circle instead of focusing. Such transforming Fresnel lenses are often used in the optical sensor systems for imaging and optoelectronic integration or in the monitoring devices for automatically adjusting the output signal from the four-quadrant photodetectors. These structures can be easily made by a diamond cutting method [16–17]. This method provides a manufacture of Fresnel optics with refractive surfaces having minimum of optical defects due to the almost mirror-like quality of the working surfaces of the diamond cutting tools. The quality of formed images, in turn, is also very high.However, the refractive angles for sequential microprisms in the lens made but a diamond cutting can be changed only discretely, and only the discrete images can be formed. The value of above discreteness is determined by the width of the circular focusing zones, so the size of such zones should not be too large. It is proposed the method for simulating microrelief structures with the flat conical working faces for creating transforming Fresnel devices that form an almost uniformly illuminated light circle in the focal plane. The geometrical parameters of the relief for circular light beam concentrators are calculated. Some samples of such focusing microprismatic devices having been manufactured according to our simulation results were investigated experimentally. Fig.: 13. Refs: 8 titles.

Flat Fresnel lenses are known to form a point image in the focal plane. However, several practical applications require transforming lens to concentrate a parallel light beam into a uniformly illuminated light circle. We previously proposed a novel algorithm for simulating such a transforming Fresnel concentrator. In this study, we applied this method to the diamond-cutting technique to create prismatic refractive surfaces of high optical quality. To reduce the discreteness of formed images, each refractive lens zone was fabricated from several small identical microprisms in the simulation. The new fabricated circular light beam concentrators were investigated by computer modelling and experimentally with a collimated laser beam.

A method for determining resolution of images through prisms using test patterns is proposed. This technique is more precise than the traditional method for measuring visual acuity, which involve ophthalmologic test charts and questioning patients. An experimental setup allowing the measurement of image resolution was developed. Comparative characteristics were obtained for “Gulden Ophthalmics“ (USA) monoprisms, for “3M™Press-On™” (USA) elastic films with microrelief and for new rigid protected Fresnel microprisms developed at the Institute for Information Recording (Ukraine). The reasons for the decrease in image resolution and visual acuity are discussed for all of the investigated ophthalmic monoprisms and microprisms.

The Fresnel-prism technique has become an important medical option for the diagnostics and treatment of strabismus in children. However, the application of prisms in ophthalmology generally involves chromaticity problems: the formed optical images are distorted due to the dispersion of white light at the microrelief and the applied microprisms reduce the contrast of the images of the test charts, and in turn, the accuracy of eye diagnostics drops. In this study, a novel method was developed for the total chromatism compensation using a special microprismatic refractive–diffractive structure with double microrelief: the first refractive microrelief was used for light beam deflection, whereas the second diffractive one was used for compensating the chromatism of the first microprism. The dispersion chromatism of the first refractive prism and the diffraction chromatism of the second microprism grating are oppositely directed. Thereby, dispersion chromatism can be completely compensated by diffraction grating. The optimal characteristics of these achromatic refractive–diffractive structures were calculated, and the necessary angles and optimal relief pitches of the ophthalmic microprisms were obtained. Achromatic structures were manufactured according to the calculated parameters, and their optical characteristics were experimentally investigated. The main advantage of such optical devices is that they are flat and very thin. The findings indicate the possibility of designing effective achromatic microprisms.

The improved scheme of data recording process on an optical disc based on a substrate made of high-stable materials has been proposed. Information layer with depth of 115nm and width of 600nm has been obtained on sapphire substrate by ion-beam etching using improved scheme. These experimental results allow to create the sapphire optical discs for long-term data storage.

The possibility of using semiconductor laser interferometers to measure displacements at the nanometer scale was demonstrated. The creation principles of miniature digital Michelson interferometers based on semiconductor lasers were proposed. The advanced processing algorithm for the interferometer quadrature signals was designed. It enabled to reduce restrictions on speed of measured movements. A miniature semiconductor digital Michelson interferometer was developed. Designing of the precision temperature stability system for miniature low-cost semiconductor laser with 0.01oС accuracy enabled to use it for creation of compact interferometer rather than a helium-neon one. Proper firmware and software was designed for the interferometer signals real-time processing and conversion in to respective shifts. In the result the relative displacement between 0-500 mm was measured with a resolution of better than 1 nm. Advantages and disadvantages of practical use of the compact semiconductor digital interferometer in seismometers for the measurement of shifts were shown.

Potentialities of the methods of information processing, distribution, and storage are analyzed. Directions are defined in which optical information media characteristics can be improved. Possibility of using optical media for a long-term storage of digital information is considered.

Results of numerical simulation of near-field optical data storage using microstrip probe are presented. Simulation is carried out on the basis of the finite-difference time-domain method. Features of the information reading process from the ROM and RW (based on the phase transmissions of Ge2Sb2Te5 film) formats of optical discs under illumination and illumination-collection mode are analyzed and considered. Mathematical modeling has shown that the signal from the ROM-format disc under illumination mode, despite the fact that the probe has a significant far-field transmission coefficient, has a large crosstalk and small spatial resolution (significantly worse than a size of probe aperture). Unlike illumination mode, signal under illumination-collection mode (pure near-field method) has a resolution close to the size of the aperture, good amplitude and contrast, as well as relatively low crosstalk. However, information reading under illumination-collection mode from RW-format disc is not able to get the same good quality signal. Therefore the further optimization of the method is required to improve the signal quality of RW format.

Results of implementation of technical solution for long term data storage technology on the basis of single crystal sapphire are presented. The effect of birefringence on the distribution of the focused laser beam through a uniaxial birefringent medium having a vertical orientation of the optical axis is analyzed. An expression for the calculation of the geometric aberrations of the focused laser beam in single-crystal substrate of the optical disc has been presented. It is shown that the problem of data reading through a substrate of negative single crystal sapphire can be solved by using for reading a special optical system with a plate of positive single crystal materials. The experimental results confirm the efficiency of the proposed technical solution.

Main ion-beam etching techniques for creation of nanostructures on the surface of high-stable materials have been considered. Methods of information recording in the form of nanostructure on the metallic substrate surface have been analyzed. Application of glass substrate for creation long-term data carrier was proposed. Microrelief information record on the glass substrate surface was obtained using the ion- beam etching.

Optical discs are widely used for storage of archival data represented in a digital form. Long-term storage of information recorded on standard CDs is provided by periodical rewriting (once in 3-5 years) on the new carriers. High-stable lightsensitive materials and special reflective metal coatings are proposed to use for increasing the information storage terms of the optical discs. The conducted researches have showed that the application of vitreous chalcogenide semiconductors in optical WORM discs assures the data storage terms up to 30 years. Substantially larger terms of data storage can be realized on the optical ROM carriers. Attainment of the guaranteed data storage terms within several hundreds years is provided in such carriers by applying high-stable materials substrates and information should be represented in the form of a micro-relief structure on the substrate surface. Sapphire, quartz, silicon, glass-ceramics and other materials can be utilized for manufacturing substrates of optical BD discs (and other subsequent high-density disc formats). These materials allow creating substrates characterized with increased melting temperature, chemical and mechanical resistance. Furthermore, using the mentioned materials for substrates production permits applying high temperature materials, such as chrome and nickel, to creation of high-stable refractive layers and demonstrating the sufficient mechanical adhesion between the refractive layer and the substrate. Modern methods of thermo-lithography offers creating of nano-size images on photo-resist layer deposited on the substrates. Those images can be transformed to the nano-size relief structures on the surface of the high-stable materials substrates by techniques of reactive ion-beam etching.

In present report the methods of the identification marks creation on the surface which are intended for the determination of licensability of CD production are considered. The main attention is devoted to the methods of the identification marks recording on master disks during the process of CD fabrication.

Results of researches of processes for forming visually observable identification elements on CD substrates are given. The opportunity of forming identification elements in an area of information block recording without data distortion is shown. The results of experimental researches on recording holographic identification elements on CD substrates are presented.

The results of experimental and theoretical investigations aimed at applying non-organic photoresists for mastering optoelectronic devices are represented. Samples for investigations were prepared using thermal evaporation of the glass with different As-S-Se compositions in vacuum onto a glass substrate. When exposing photoresist to obtain interference 2D/3D patterns, we used He-Cd laser irradiation with the wavelength 440 nm. The exposure was chosen from 20 to 150 mJ/cm 2 , and spatial frequencies of obtained gratings were from 600 to 3600 mm -1 . The resist samples were processed using a waterless organic selective etchant based on amines. Results of investigations showed that As 40 S 60-x Se x (x=0-20) photoresist is characterized by higher holographic sensitivity (i.e. energetic expose necessary for providing given value of the diffraction efficiency). This enables us to create various combined optical-digital protective elements and master-copies for all types of optical disks (CD, DVD).

The present work contains results of the investigations of the master disks manufacturing process and the following stamp plating process for compact disk duplication. The salient feature of the process under consideration is the use in a master disks as a photosensitive material of the vacuum deposited organic dye layer, the relief image on which is formed directly in the irradiation-recording process. In the work are considered the master disks manufacturing process. An organic dye is deposited by the thermal vacuum evaporation method. This provides the thickness test of a coating directly during the manufacturing process, the high purity of a photosensitive layer and its very high uniformity in thickness.

Production of high quality master discs used in CD manufacturing process is possible only at light-sensitive material exposure process optic control carrying out and relief image production. High precision of relief image production process control on the master disc surface is provided in case of relief formation in the process of data recording. The results of optical discs mastering using direct reading technology (recording quality control) in the process of recording are considered below. The high- sensitive material composition selection effect upon pit form is given. The conditions in which the light-sensitive layer material is practically completely removed from master disc surface are defined. The after-record direct reading method comparison to the method of image production using photoresists is given.

Photoluminescent spectra of CaO, MgO oxides, doped with rare-earth ions have been studied. The stimulated by IR- light photoluminescence in these materials has discovered at room temperature for the first time. Optically stimulated luminescence in Ca(Mg)O: Eu, Sm for different concentrations of dopants after exposure to UV-radiation ((lambda) equals 250 nm) and radiation with (lambda) equals 488 nm has been investigated. The physical model to explain luminescence and stimulated luminescence mechanism is proposed. Materials on the base of alkaline-earth oxides activated by rare-earth ions are suitable for multiple rewrite of information.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The optical memory on materials having the properties of electron trapping is a new direction at development of information storage and rewrite. Currently are pursued investigations directed on creation of a new type recording medium with the opportunity of information rewrite by optical methods as well as a medium for heteroassociative memory in optical neural systems. Primarily as such medium are used alkaline-earth metal sulphides activated by two rare-earth elements. When creating the memory on materials with electron trapping on the basis of alkaline-earth sulphides there arises a number of difficulties: (1) these materials are chemically unstable, especially they are subject to the action of water vapors; (2) films prepared by electron-beam evaporation technique have a polycrystalline structure with grain sizes in the order of 20 nm what has an essential influence on the signal-to-noise ratio at information reading. The main objective which is pursued by us consists in investigating the optical properties of new synthesized materials having the electron trapping properties which are characterized by chemical stability and are easy manufacture at preparation of amorphous structures. We have also recommended to use CaO (MgO) doped with Eu, Sm. It has known, that the optical stimulated luminescence (OSL) obtains in CaO. But OSL appears in the special prepared structures with defects. For this aim there are some methods: thermochemical reduction or radiation processing by electron beam. Besides that the OSL obtains only by nitrogen temperature (77 K).© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A work by a computer with input analog signals like a sound and graphics has some features in contrast to work with other forms of information. And one of the very essential differences is a data transfer continuity. Pauses when being transferred a sound or stoppages of frames take place owing to warm backup in up-to-date compact hard disk drives (HDD). HDD suspends its work and gives read-write heads an opportunity to adjust themselves to changed thermal conditions. Every time this procedure breaks a data transfer continuity in a computer. It is known, that the famous manufacturer such as 'MICROPOLIS' (from 1993) and 'SEAGATE' (from 1994) produce some specialized (with cache memory) HDD with capacity up to 9 Gb to audio and video applications. As one of such problem solutions there is proposed a new volume memory mechanism based on using of the energy thin structure in organic molecular crystals such as anthracene, tetracene, and pentacene. These crystals are solid state systems and have more complicated structural organization than inorganic, covalent andion crystals. The modern level of organic chemistry development give almost unlimited opportunities of such crystals synthesis.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

On the basis of the opticorefractometric regularity (OR) the possibility of a computer design of an acousto-optical Q- factor (AOR) data bank is shown. Taken as an example the novel complex halogenides the investigations have been carried out. The obtained results in comparison with well- known from world scientific works are given. It is shown that such approach is very important for producing IR- and UV-deflectors.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

At present there exist many methods of preparing film structures on an inner surface of cylindrical elements by vacuum technology. They are designed for evaporation of metallic, oxide and other surface layers mainly and cannot practically be used for the formation of optical layers using multi-component, strong dissociative materials. Therefore we have developed the flash evaporation method using fiber as a film-forming material. This method allows us to obtain defect-free, x-ray amorphous, uniform over the thickness recording layers from multi-component strong dissociative materials.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The changes in optical properties of thin films of vitreous chalcogenide semiconductors in the pro cess of long-duration storage are studied. The feature of films composition influence and their preparation on the long-duration process are established.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

To overcome the limitation of the current memories some authors developed method for storing data throughout a volume of memory material using two-photon absorption effect. In this work we represent the three-dimensional vector analysis of diffraction laser beam by the simple model of this volume data storage. We represent the volume data storage as homogeneous dielectric in which three- dimensional grating of spheres with complex (epsilon) , (mu) are located. To evaluate scattering field of partial wave we used Lorenz-Mie theory. The total scattering field is sum of partial scattering fields and some small addition field of re-radiation. The addition field of re-radiation was evaluated in first approach of perturbation theory. The investigation results were used for the determination of recording information limits into the memory material.

In the present paper the algorithms and programs have been proposed for computer design of data bank based on optico -- refractometric regularity (OR) and X(alpha ) -- approach while calculating photoinduced changes (PC) in complex pniktido-chalcogenides to be used for ablative information recording.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The description of a method for optomechanical sound reproduction from Edison cylinders the distinctive feature of which is recording the surface profile of the cylinder sound track with its subsequent conversion into sound by means of a computer is presented. With the purpose of decreasing the destructive influence of reproduction system on the cylinder surface the recording the surface profile of a sound track is carried out at rotational speed smaller by a factor of 20 - 30 of that one at which was executed the information recording on it. The realization of a proposed method allowed to reproduce information recorded on cylinders with minimal action and to obtain a high quality of a reproduced signal.

Single crystals of general molecular formula ABX3, where A is a monovalent ion (A+) equals Tl+, Cs+), B is a divalent element (B2+ equals Cd2+, Pb2+), and X equals Cl/Br, belong to an important class of halide crystals that attract attention of investigators due to their interesting properties and various phase transition mechanisms. Some structure sensitive and acousto-optical parameters were obtained from the experimental results. The temperature behavior of the dielectric permittivity and conductivity of these insufficiently investigated crystals in the range 250 - 550 K corresponds to a normal behavior of ionic crystals. It was found that the correlation took place between a tolerance- factor and some structure sensitive parameters of the above- mentioned crystals.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper reports the findings from an experimental evaluation of speckle suppression efficiency using a method based on a moving 2D Barker code diffractive optical element (DOE). The optical setup and the optical scheme parameters of the method are presented. A speckle contrast of ∼4.4–5.3% and speckle suppression coefficient (coefficient of speckle contrast reduction) of k>8 was obtained in experiments. However, the experimentally obtained speckle suppression coefficient was approximately 1.5 times smaller than the theoretical prediction. It is speculated that the discrepancy between the theoretical and the experimental data is due to an inexact match between the optical setup and the optimal optical parameters of the method. Analysis of the experimental data revealed that once the optical scheme is optimized, it will be possible to obtain a speckle suppression that is closer to the theoretical prediction.

A method for speckle suppression based on Barker code and M-sequence code diffractive optical elements (DOEs) is analyzed. An analytical formula for the dependence of speckle contrast on the wavelength of the laser illumination is derived. It is shown that speckle contrast has a wide maximum around the optimal wavelength that makes it possible to obtain large speckle suppression by using only one DOE for red, green, and blue laser illumination. Optical schemes for implementing this method are analyzed. It is shown that the method can use a simple liquid-crystal panel for phase rotation instead of a moving DOE; however, this approach requires a high frequency of liquid-crystal switching. A simple optical scheme is proposed using a 1D Barker code DOE and a simple 1D liquid-crystal panel, which does not require a high frequency of liquid-crystal switching or high-accuracy DOE movement.

This paper presents a new echelette optical low-pass filter that serves as a Bangerter filter (BF) for diagnosis and treatment of amblyopia and diplopia. Theoretical analysis and experimental measurements showed that echelette BFs have several advantages over the modern BFs used in medicine. Four echelette BFs with different grating periods and one BF were manufactured, and image blurring in an optical visual system with an echelette BF was experimentally investigated. The experimentally measured modulation transfer function and line spread function demonstrated definite image blurring (line expansion) that is inversely proportional to the width of the grating period. The results of measurements of the angular resolution of the optical system with an echelette BF coincide well with the results obtained by theory.

An interferometric technique of a position and beating control for an axial rotating body position is described in this paper. A Michelson interferometer without a signal spectrum transfer in a high-frequency range is used as a position and beating sensor of a rotating body. An autocollimator as a reflector insensible to angular rotating is used in a measuring level of the interferometer. The autocollimator is tightly connected with a cylindrical information carrier by a magnet lock for motion dynamics investigations. It is found that the position error of the proposed position sensor does not exceed (lambda) /8.

The process of optical recording on ablation mechanism carriers shows a peculiar microrelief. The peculiarity of the latter is in the presence of an annular rim around the pit, of the carrier material arising by action of surface tension. This force on the liquid phase of microregion was subjected to the thermal action of a laser beam. During reading for increasing the signal- to-noise ratio, it is necessary to achieve optimal relations for parameters of reading laser beam, and geometrical pit dimensions surrounded by the annular rim. The method of scalar theory of diffraction did not allow to investigate the influence of geometrical sizes rims of pits on scattering characteristics of the laser beam from pits. In this connection, the mathematical simulation problem of the informaiton reading process from the surface with such form of units is of current concern.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Wideband semiconductor based on the alkali-earth metals and doped with the rare-earth ions are sensitive to the laser irradiation in the blue spectral range. An alkali-earth sulphide doped with the rare-earth ions could be used as recording reversible media for data storage.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The aim of the present study is to establish the nature of the stimulated photoluminescence (PL) under IR excitation in the electron trapping materials. Investigations of the PL spectra of sulfides and oxides of the alkali-earth metals at the room and liquid N temperatures were carried out. Oxide hosts were exposed to electron beam irradiation in order to create defect levels for subsequent trapping of electrons. The oxide-based materials were preferably investigated because of their high chemical stability and low hygroscopicity in comparison with sulphide host material. This fact should be taken into account when using the materials as a data recording medium.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An interferometric technique of a position and beating control for an axial rotating body position is describedin this paper. A Mikelson interferometer without a signal spectrum transfer in a high-frequency range is used as aposition and beating sensor ofrotating body. An autocollimator as a reflector insensible to angular rotating is usedin a measuring level ofthe interferometer. The autocollimator is hard connected with a cylindrical informationcarrier by amagnet lockformotion dynamicsinvestigations. his foundthe positionerrorofthe proposed position sensor is no more A/8. Keywords: interferometer, phase shift ,lightbeam, autocollimator, polarization vector, wave front.2. INTRODUCTIONMany scientific and technical applications need precise displacement measurements of an axial rotatingcylindrical body.In a manufacluring industry this problem usually appears at detail machining with a submicron workingaccuracy when adynamicbeating andaposition control ofarotatingmachiningtool isneeded. Now interferometersa.reusedin such machinary. These interferometers check only adisplacement ofamachine toolheadwith a rotatingtool placed in it. But the same time a beating control ofa machining tool is absentThe control problem of a rotating cylindrical body control appears also at a detail manufacturing ofelectro-vacuum macbinary for complex drawings plotted on cylindrical surfaces with a submicron accuracy.In optical memory devices this problem is particularly actual for cylindrical information carriers used intheirs1. An interferometer location control technique is used in such devices dynamics investigations of axialmotion in cases for an autotrcing with submicron surface tracks and a carrier displacement control.However abovementioned problems can

As an alternative to recording media on the tellurium base, recording media built in the form of matrix structures in which a photo(thermo)active component is included into the matrix can be used. We suppose that the most effective preparation method of such media which provides the deposition on substrates of any form can be a dissociation method of organometallic compounds (OMC). Depending on the choice of OMC, atmosphere in which occurs its decomposition, additions and conditions of process following there can be obtained by polymerization of OMC ligands in which is distributed a metal phase (metal-polymeric media) and an oxide matrix in which are implanted organic ligands changing its parameters. The gradient metal spreading was created by increasing the pulse amplitude of voltage discharge from 500 to 2000 V. The content of metal was increased in direction from substrate and was near substrate 0 - 10 at percent and near free film surface up to 80 at percent. The film composition was investigated by means of the layer-to-layer auger analysis using microscope JAMP-10 S. The comparative analysis of Raman spectra of starting OMCs and prepared from them films showed the advent of new bonds of the type metal-metal, carbon-carbon and the decrease of bonds quantity of the type carbon-carbon, metal-ligand. The action of focused laser radiation on such films leads to formation of microholes in the center of the irradiation region and on peripheral areas it leads to an additional OMC decomposition.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The results of technical determination analysis are given; this analysis had been used while creating mass memory on optical cylinders. The distinctive features of accumulators on the cylinder carriers are considered.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The results of the experimental investigation of the interaction process of focused laser radiation with metal-polymer films with uniform and gradient metal spreading are presented. A model construction of this process and focused laser radiation diffraction on pits are discussed.

Owing to unique optical properties the alkaline-earth sulphides doped with rare-earth ions find wide application as electroluminescent devices t1,2], .7.' radiation counters ES] as well as recording media of optical information carriers with the possibility of multiple information rewriting (4—7].

The immersion system of information recording on optical cylinders is considered. The investigation results of system aberrations caused by the presence of cylindrical surfaces, immersion liquid by the change of such parameters as thickness, refractive index are presented. The recommendations on correction of such main system aberrations as spherical and astigmatism are proposed. The possibility of creation of high-aperture aspherical immersion objectives for information recording is shown. On experimental specimens of immersion-type information recording devices on optical cylinders is obtained the density of 8x11 It/mm.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The thermal crystallization process dynamics in a reversible recording medium on the base of chalcogenide semiconductors was studied by means of numerical simulation. The Kolmogorov-Avraami equation was used for nonisothermal crystallization process simulation. The spatial-temporal distribution of crystalline phase in the writing area was obtained. The writing modes under which a uniform distribution of crystalline phase in the irradiated area is achieved were investigated.

Theoretic research and experimental investigations are showing the possibility of repeated information recording and read-out on new recording media with optically stimulated luminescence (OSL) effect. OSL concentration and spectral dependencies in Ca(Sr)S:Eu2+(Ce3+)-Sm3+ were determined. OSL in CaS films doped only by Sm3+ ions was detected.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The results of the process of irreversible optical bit-by-bit recording on metal-polymeric films obtained by the method of plasma metal organic chemical vapor deposition are presented. The dependence between conditions of producing recording media and their properties has been established. The comparison of recording process on metal-polymeric antimony recording media with data recording on tellurium alloy films has been carried out.

The properties of metal-polymeric recording media obtained by the decomposition of alkyl tin (Sn) and antimony (Sb) compounds in low-temperature plasma have been investigated. We have experimentally determined the changes of pit shapes during the photothermal recording and the basic medium characteristics when changing the metal and carbon concentrations in the films.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper discusses, for the first time, the possibility of application of new recording medium with the effect of photoluminescence. Optimization parameters of four-layer recording medium were held with the purpose of effective use of energy of recording and read-out radiation and getting maximum signal-to-noise ratio.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Photoluminescent (PL) spectra of Sn02, 1n203, Y203, Yb203, CaO oxides andtheir mixtures, dopted with rare-earth ions have been studied. The possibility of their use for electroluminescent (EL) displays was considered. It is shown, thatunder Ar laser exitation of the luminescence one can get display color range fromgreen to red. FL spectra of oxides with Eu are characterized3 by the substanti-ally greater set of emission lines than for the oxides with Ce . It indicates that the degeneracy of 7F1,2 levels in Eu3 luminescence centers is removed. Raman spectra studies allowed to identificate the impirity ion Eu symmetry in oxide matrices. It corresponds the C3v group. The ion Ce symmetry under sub- stitution . . In 3+ 2+ 3+ 3+ . . . . . , Sn , Y for Ce in the oxide lattice is substantially higherthan C3v, therefore the FL spectrum containes only two lines in the visible range, and their energy position slightly depends on the oxide matrix type. 1. INTRODUCTION Alkali-earth sulfides doped with rare-earth elements now are used as matricesfor electroluminescent displays. However, ZnS, SrS, CaS sulfides are chemicallyunstable and hygroscopical, so one has to make additional stabilization of dis-plays, based on this materials. Furthermore, the important problem is to obtainthin films, responsible for multicolor display, particularly, blue color. Use

The authors propose a method to increase the information recording density in optical storage by means of optical immersion. The influences of parameters of information carrier substrate and moving immersion liquid flow on the aberrations of information recording-reading optical channel are investigated. It has been shown that in the case of optical immersion data recording the most acceptable information carrier was a carrier shaped as an optical cylinder. The information recording in such an optical cylinder is performed on its internal surface. The recording media and the method of depositing these media on the cylinder's internal surface are analyzed. The technical characteristics for the immersion type optical storage are given.

The possibility of data recording in alkaline-earth phosphors doped with rare-earth ions is demonstrated. The results of experimental studies of optical, electronic, and structural properties of SrS and CaS alkaline-earth sulfides activated by Eu (Ce) and Sm ions are reported.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.