Method of making crystalline workpieces of solid solutions of silver halides for optical components |
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IPC classes for russian patent Method of making crystalline workpieces of solid solutions of silver halides for optical components (RU 2486297):
 Flat lens made from leucosapphire and method of making said lens / 2482522
Flat lens made from leucosapphire is made from a plastically deformed workpiece, wherein the axis of symmetry of the flat lens coincides with the height of the cone of optical axes of the plastically deformed workpiece. The entrance and exit surfaces are flat and perpendicular to the axis of symmetry. The method of making the flat lens involves making a concave-convex workpiece by plastic deformation - bending the plane-parallel plate from the Z crystal cut. The lens is formed by removing an excess layer of material from the workpiece as a plane-parallel plate, perpendicular to the axis of symmetry of the workpiece, which is superposed with the axis of the cone of optical axes, of a given thickness. The entrance surface of the flat lens lies at a distance x<δ from the vertex of the workpiece, where δ is the thickness of the workpiece.
 Mould and method of its making / 2482221
Mould for formation of a moth eye structure on the surface comprises a base from glass or plastic, an inorganic sublayer, a buffer layer, containing aluminium, an aluminium layer and a porous layer of aluminium oxide, having on the surface a tilted structure of moth eye with multiple grooves, the size of which in two dimensions visible in direction of the normal line to the surface makes at least 10 nm and less than 500 nm. The method includes the following stages: (a) the mould base is provided from glass or plastic, an inorganic sublayer, a buffer layer, containing aluminium, and an aluminium layer, (b) the aluminium layer is partially anodised for formation of the porous layer of aluminium oxide with multiple grooves, (c) the porous layer of aluminium oxide is exposed to etching, increasing grooves in the porous layer in size, and (d) the porous layer of aluminium oxide is anodised for growth of grooves.
 Method of producing photonic-crystal structures based on metal oxide materials / 2482063
Invention relates to opto- and microelectronics and can be used to make opal-like structures. The method of producing photonic-crystal structures based on metal oxide materials involves filling a template consisting of monodispersed micropheres of polystyrene, solutions of metal-containing precursors, followed by annealing the structure on air at temperature of 450-550°C for 8-10 hours. The precursors from which the structure is formed are saturated alcohol solutions of tin dichloride SnCl2·2H2O or zinc nitrate Zn(NO3)2·2H2O.
 Mould and method of its production / 2481949
Inventions relate to mould intended for moulding antireflection structure on moulded product. Proposed mould comprises flexible polymer film, layer of cured resin arranged thereon and layer of porous aluminium oxide made on aforesaid layer. Porous aluminium oxide layer has reverse prominent surface structure. Said structure has multiple recesses. Size of said recesses, if seen in perpendicular direction to said surface, varies between 10 nm and 500 nm. Flexible roller-shaped mould can be arranged on substrate outer surface. Said mould is used to form antireflection structure on polarisation plate. For this, said plate is displaced relative to mould. Note here that prior to forming said structure, polarisation plate axis is properly arranged parallel with roller perimetre, roller length making 2πr, where r is roller radius.
 Antireflective film and method of making said film / 2480796
Antireflective film which reduces reflection of visible light on the surface of a substrate has a wavelength dispersion structure for causing a first wavelength dispersion of visible light passing through said antireflective film, and contains wavelength dispersion material for causing a second wavelength dispersion of visible light passing through said antireflective film. Visible light in the range from 380 nm to 780 nm, passed through the antireflective film, has light transmission fluctuation which is less than 0.5% of the transmission value at wavelength of 550 nm. The method of making the film involves depositing a visible light-cured resin onto the substrate which has a UV absorbing component in order to form a film; forming a rough part on the surface of the film, having a plurality of protrusions; the space between peaks of neighbouring protrusions is equal to or less than the wavelength of visible light; irradiating the film with visible light on the side of the substrate and curing the film to form an antireflective film.
 Antimicrobial polymer products, methods of their obtaining and methods of their application / 2476072
Claimed invention relates to ophthalmological device, method of its obtaining. Device contains antimicrobial particles of metal salts, which have size less than approximately 200 nm, dispersed throughout polymer mass. Device ensures at least 0.5 log reduction of at least one of Pseudomonas aeruginosa and S.aureus, and opacity value constituting less than 100%, with 70 micron thickness, in comparison with CSI lens.
 Method of forming clear wettable articles from silicone hydrogel / 2469053
Provided is a method of making ophthalmic devices such as contact lenses, involving steps of curing a reactive mixture containing at least one silicon-containing component, at least one hydrophilic component and at least one protonating diluent or protonated diluent having a Hansen solubility parameter, dp between about 2 and about 7 to form an ophthalmic device having an advancing contact angle of less than about 80°; and bringing the ophthalmic device into contact with an aqueous solution which is capable of altering the Hansen solubility parameter, dp of the protonating or protonated co-solvent in order to increase water-solubility and remove said diluent(s) from said aqueous solution.
 Optical element, optical component with antireflection function and source die mould / 2468398
Optical element has a base and a large number of structures lying on the surface of the base. The structures are protrusions or depressions and lie with spacing which is less than or equal to the wavelength of light under conditions of use. The effective refraction index in the direction of the depth of the structures gradually increases towards the base, and the curve of the effective refraction index has two more points of inflexion. The structures can be arranged in form of a hexagonal array, a quasi-hexagonal array, a quadrilateral array or a quasi-quadrilateral array. The structures have two or more steps between the peak and the bottom part of the structures and have a peak and/or a bottom part; or the structures have a curvilinear surface and become wider from the peak to the bottom part; or change in the effective refraction index in the direction of the depth of the structures on the upper side of the structures is greater than the average value of the effective refraction index on the slope of the structure; or change in effective refraction index in the direction of the depth of the structures on the side of the base of the structures is greater than the average value of the effective refraction index on the slop of the structure.
 Anti-reflection film and display device / 2468397
Anti-reflection film has on the surface a thin rough structure, wherein the width between adjacent top points is equal to or less than the visible wavelength. The half-value angle of luminous intensity distribution for scattering when transmitting light which is transmitted through two overlapping sheets of the anti-reflection film is equal to or greater than 1.0°.
 Method of forming thermosensitive nanocomposite photonic crystals / 2467362
Method can be used in designing temperature sensors for optoelectronic systems. The method involves introduction of material with external temperature-variable properties into an opal structure obtained by etching colloidal particles which form the crystal lattice of a photonic crystal with the introduced opal, whose introduction is carried out by infiltrating an opal oxide precursor. The initial structure for the photonic crystal is formed by polystyrene particles via deposition on a flat substrate. Infiltration of the opal oxide precursor into the initial opal structure is carried out at pressure which is 1.2-1.5 times higher than atmospheric pressure and temperature 60-80°C. The introduced material is a mesomorphic substance which is a cholesteric liquid crystal, which is introduced by saturating at temperature higher than the temperature for transition of the liquid crystal an isotropic state (from 70°C), and at pressure 150-200 kPa, with a final operation for depositing onto the surface of the photonic crystal a metal layer with thickness of 150-300 nm by magentron sputtering at a rate of 20-40 nm/min in order to improve stability of the structure when heated.
 Laser fluoride nanoceramic and method for production thereof / 2484187
Fluoride nanoceramic is obtained by thermomechanical treatment of the starting crystalline material made from CaF2-YbF3, at plastic deformation temperature to obtain a workpiece in form of a polycrystalline microstructured substance, which is characterised by crystal grain size of 3-100 mcm and a nanostructure inside the grains, by annealing on air at temperature of not less than 0.5 of the melting point with compaction of the obtained workpiece in a vacuum at pressure of 1-3 tf/cm2 until the end of the deformation process, followed by annealing in an active medium of carbon tetrafluoride at pressure of 800-1200 mmHg. The starting crystalline material used can be a fine powder which has been subjected to heat treatment in carbon tetrafluoride, or a moulded workpiece of crystalline material made from the powder and heat treated in carbon tetrafluoride.
 Method of diamond heat treatment / 2471542
Invention relates to processes used in operation at high pressure and modifying substances physically. Proposed method comprises placing diamond in reaction cell in pressure transmitting medium, increasing pressure in reaction chamber and it cooling. Note here that thermal treatment is carried out at temperature increase rate of 10-50°C/s and at 2000-2350°C by passing electric current via heater in cell from programmed power supply source with due allowance for temperature relaxation in said cell in heating. For this, note also that temperature relaxation constant is defined. Said cell is cooled after heating by switching off power supply in forming short diamond heating pulse in temperature range of over 2000°C with diamond total stay time smaller than 30 seconds. Allowance for temperature relaxation in said cell in heating for heating rate Vt and pre-definition of cell temperature relaxation constant τ is made by setting in said programmable power source the maximum temperature of heating to τVT above maximum treatment temperature of 2000-2350°C.
Method of thermal treatment of abrasive tool (at) / 2467100
Invention relates to production of abrasive tools intended for machining metals and alloys. Proposed cycle of processing AT at TTB comprises heating AT at 2450 Hz in microwave chamber for near-100 mm-thick AT and at 890-915 Hz for over-100 mm-thick AT to complete polymerisation (hardening) and curing semis at said temperature with uniform forced removal of volatile matters released therefrom (hot vapor-gas mix) from thermostat free volume by airflow created by exhaust vent system of microwave chamber via slots made in thermostat front and rear walls to rule out saturation of said volatile matters. Temperature of processed semis is controlled by device incorporated with thermostat and airflow forced in thermostat is heated to temperature of semis.
 Method of diamond processing / 2451774
Invention relates to diamond processing, in particular, by thermochemical process. Proposed method comprises applying layer of spirit glue composition onto diamond surface, said composition containing transition metal, for example, Fe, Ni or Co, and processing diamond thermally at temperature not exceeding 1000°C. To prepare spirit glue composition, powder of water-soluble salt of transition metal is used. Said powder in amount of 1-10 wt % of water solution is mixed with spirit solution of glue at salt water solution-to-glue spirit solution ratio of 1:1. Prepared mix is applied on diamond surface in 10-20 mcm-thick layer to be dried. Thermal processing of diamond is performed in two steps. Note here that, at first step, diamond is processed at 600-700°C for 1-2 min, while, at second step, it is processed at 800-1000°C for 15-30 min.
Method of producing fluoride nanoceramic / 2436877
Method involves thermomechanical processing of initial crystalline material made from metal halides at plastic deformation temperature, obtaining a polycrystalline microstructured substance characterised by crystal grain size of 3-100 mcm and intra-grain nanostructure, where thermomechanical processing of the initial crystalline material is carried out in vacuum of 10-4 mm Hg, thus achieving degree of deformation of the initial crystalline material by a value ranging from 150 to 1000%, which results in obtaining polycrystalline nanostructured material which is packed at pressure 1-3 tf/cm2 until achieving theoretical density, followed by annealing in an active medium of a fluorinating gas. The problem of obtaining material of high optical quality for a wide range of compounds: fluoride ceramic based on fluorides of alkali, alkali-earth and rare-earth elements, characterised by a nanostructure, is solved owing to optimum selection of process parameters for producing a nanoceramic, which involves thermal treatment of the product under conditions which enable to increase purity of the medium and, as a result, achieve high optical parameters for laser material.
 Procedure for surface of diamond grains roughing / 2429195
Procedure for surface of diamond grains roughing consists in mixing diamond grains with metal powder and in heating obtained mixture to temperature of 800-1100°C in vacuum as high, as 10-2-10-4 mm. As metal powders there are taken powders of iron, nickel, cobalt, manganese, chromium, their alloys or mixtures. Powders not inter-reacting with diamond grains at heating can be added to the mixture.
Method of annealing crystals of group iia metal fluorides / 2421552
Method involves subjecting a grown and hardened, i.e. correctly annealed crystal, to secondary annealing which is performed by putting the crystal into a graphite mould, the inner volume of which is larger than the crystal on diameter and height, and the space formed between the inner surface of the graphite mould and the surface of the crystal is filled with prepared crumbs of the same material as the crystal. The graphite mould is put into an annealing apparatus which is evacuated to pressure not higher than 5·10-6 mm Hg and CF4 gas is then fed into its working space until achieving pressure of 600-780 mm Hg. The annealing apparatus is then heated in phases while regulating temperature rise in the range from room temperature to 600°C, preferably at a rate of 10-20°C/h, from 600 to 900°C preferably at a rate of 5-15°C/h, in the range from 900 to 1200°C preferably at a rate of 15-30°C/h, and then raised at a rate of 30-40°C/h to maximum annealing temperature depending on the specific type of the metal fluoride crystal which is kept 50-300°C lower than the melting point of the material when growing a specific crystal, after which the crystal is kept for 15-30 hours while slowly cooling to 100°C via step-by-step regulation of temperature decrease, followed by inertial cooling to room temperature.
 Method of thermal treatment of single-crystal substrate znte and single-crystal substrate znte / 2411311
Method includes the first stage of increasing temperature of single-crystal substrate ZnTe up to the first temperature of thermal treatment T1 and maintenance of substrate temperature within specified time; and the second stage of gradual reduction of substrate temperature from the first temperature of thermal treatment T1 down to the second temperature of thermal treatment T2, lower than T1 with specified speed, in which T1 is established in the range of 700°C≤T1≤1250°C, T2 - in the range of T2≤T1-50, and the first and second stages are carried out in atmosphere of Zn, at the pressure of at least 1 kPa or more, at least 20 cycles or at least 108 hours.
 Method of growing heat resistant monocrystals / 2404298
Crystals are grown using the Kyropoulos method with an optimum annealing mode, carried out while lowering temperature of the grown monocrystal to 1200°C at a rate of 10-15°C/hour and then cooling to room temperature at a rate of 60°C/hour.
Method of producing monocrystals of calcium and barium flourides / 2400573
Method involves crystallisation from molten mass through Stockbarger method and subsequently annealing the crystals through continuous movement of the crucible with molten mass from the upper crystallisation zone to the lower annealing zone while independently controlling temperature of both zones which are separated by a diaphragm. The crucible containing molten mass moves from the crystallisation zone to the annealing zone at 0.5-5 mm/h. Temperature difference between the zones is increased by changing temperature in the annealing zone proportional to the time in which the crucible moves from the beginning of crystallisation to its end, for which, while maintaining temperature in the upper crystallisation zone preferably at 1450-1550°C, in the lower annealing zone at the beginning of the crystallisation process temperature is kept at 1100-1300°C for 30-70 hours, thereby ensuring temperature difference of 450°C between the zones at the beginning. Temperature of the annealing zone is then lowered to 500-600°C in proportion to the speed of the crucible with the growing crystal. Temperature of the annealing zone is then raised again to 1100-1300°C at a rate of 20-50°C/h, kept for 18-30 hours after which the zone is cooled to 950-900°C at a rate of 2-4°C/h, and then at a rate of 5-8°C/h to 300°C. Cooling to room temperature is done inertially. Output of suitable monocrystals of calcium and barium fluorides with orientation on axes <111> and <001>, having high quality of transparency, uniformity, refraction index and double refraction is not less than 50%.
Laser fluoride nanoceramic and method for production thereof / 2484187
Fluoride nanoceramic is obtained by thermomechanical treatment of the starting crystalline material made from CaF2-YbF3, at plastic deformation temperature to obtain a workpiece in form of a polycrystalline microstructured substance, which is characterised by crystal grain size of 3-100 mcm and a nanostructure inside the grains, by annealing on air at temperature of not less than 0.5 of the melting point with compaction of the obtained workpiece in a vacuum at pressure of 1-3 tf/cm2 until the end of the deformation process, followed by annealing in an active medium of carbon tetrafluoride at pressure of 800-1200 mmHg. The starting crystalline material used can be a fine powder which has been subjected to heat treatment in carbon tetrafluoride, or a moulded workpiece of crystalline material made from the powder and heat treated in carbon tetrafluoride.
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FIELD: chemistry. SUBSTANCE: method involves loading starting separate silver chloride and silver bromide salts into a container made of heat-resistant glass, fusing said salts to a given composition of solid solution, growing a monocrystal in a halogenating atmosphere by moving the container in a temperature gradient, cooling the grown crystal to room temperature and removing the crystal from the container; the monocrystal is then heated at a rate of 50-60°C per hour to temperature of 250-270°C, held at said temperature for 1-2 hours, cooled at a rate of 20-25°C per hour to temperature of 100-150°C and then cooled at a rate of 30-40°C per hour to room temperature. EFFECT: reduced internal stress in the crystalline workpiece, improved optical homogeneity and reduced optical losses. 2 ex
The invention relates to the field of materials transparent in the infrared region of the spectrum, namely crystals of silver halides which can be used for the manufacture of optical elements transparent in the region of wavelengths from 0.4 to 15 μm, and for the manufacture of optical fibers of the middle IR range. A method of obtaining single crystals of silver halides and thallium, including fusion of the original salt of halide in a darkened glass ampoule under vacuum, with subsequent crystallization purification of the melt from impurities. From the resulting ingot is cut enriched with impurities to an end. Clean the part of the ingot used as source material for cultivation in the vacuum crystal method stockburger-Bridgman. The obtained crystal after the growth cooled to room temperature in the free cooling mode. To prevent decomposition of the material all work with halides of silver, and thallium shall be conducted at a red light, and growing in a specially darkened vial (Ed. St. USSR. No. 149395, MKI4C30B 11/02, C30B 29/12, publ. 14.07.1961,) The known method does not allow to obtain high-quality crystalline billet of solid solutions of the halides of silver, as only the directional solidification of a melt of silver halide in which the cosmology vacuum is not enough to clear the source of salts from the oxygen-containing impurities of silver, and products of thermal decomposition of silver halides. In addition, free-cooling crystals is not sufficient to relieve internal stresses. The absorption coefficient of the laser radiation at the wavelength of 10.6 microns is grown by a known method the crystals are not better (1-3)·10-3cm-1. Optic fibers made from these crystals have optical losses more than 10-15 dB/m and very quickly darken due to the dissociation of silver halides. In the production of crystals in such a way returnable waste reaches 60-70%. A method of obtaining crystals of solid solutions of the halides of silver for the manufacture of polycrystalline fibers, including deposition of chloride and bromide of silver from aqueous silver nitrate solution, followed by rinsing and drying the precipitate. Salt was mixed by fusing and subjected to purification from decomposition products, water, organic and ionic impurities by filtering, zone melting, vacuum distillation. The crystals of solid solutions was given in capsules from heat-resistant glass "Pyrex" method vertical directional solidification (Bridgman method-stockburger) without the use of seed. After crystallization drive lowering ampoule was stopped and the temperature of the crystal was lowered from the temperature rising to room with a speed of 10-15 degrees/hour. Of receiving the data of the crystal blanks by the method of backward extrusion at a temperature of 180-190°C was crushed polycrystalline fiber fiber diameter of 0.5-1.0 mm The coefficient of optical absorption of the crystal, measured by laser calorimetry, at a wavelength of 10.6 μm was (1-3)·10-4cm-1. Optical losses are made of such crystal blanks fibers in the region of wavelengths of 2-5 μm was 3-5 dB/m (artyushenko VG, Basque PB and other Synthesis and structural properties of solid solutions AgCl1-xBrx with x=05-08. Inorganic materials, 2005, vol 41, No. 1, p.78-87). The method adopted for the prototype. The disadvantage of this method is the low mechanical strength of the grown crystals, which leads to cracking of the crystals at their thermal and mechanical processing. The low mechanical strength of the crystals is caused by internal stresses generated during single crystal growth, leading to optical anisotropy and increased optical loss in crystals. The technical result of the invention is the reduction of internal stresses in the crystal harvesting, improved optical uniformity, reduction of optical losses crystals of silver halides at a wavelength of 10.6 µm. The technical result is achieved in that in the method of obtaining crystalline preparations of solid solutions of silver halides for optical elements, including downloading the source individual salts of chloride and bromide cerebral container made of heat-resistant glass, their fusion to a given composition of solid solution, the growing of the single crystal in the halogenation atmosphere by moving the container in a temperature gradient, the cooling of the grown crystal to room temperature and removing the crystal from the container, according to the invention the grown single crystal after cooling and removal from the container is heated with a speed of 50-60 degrees per hour to a temperature of 250-270°C, maintained at this temperature for 1-2 hours, cooled at a rate of 20-25 degrees per hour to a temperature of 100-150°C, then cooled with a speed of 30-40 degrees per hour to room temperature. The invention consists in the fact that found such conditions of heat treatment grown and chilled vials to room temperature crystal of silver halide, in which occurred the internal stresses in the crystal closer to zero the value of the yield strength and scattered, unlike the prototype method, where due to the difference of coefficients of thermal expansion of the glass container and the crystal in the crystal remain internal stresses that lead to structural heterogeneity of the crystals and, in some cases - in the preparation of the crystal to extrusion, to cracking of the workpiece, When heating the billet to a temperature of 250-270°C at 50 degrees per hour internal stresses in financial p is a severe plastic deformation of the layers of the crystal close to zero yield stress and dissipate. Heating to a temperature below 250°C does not hold for the complete dissipation of internal stresses, so as not reached the yield strength of the silver halide. Heating with a rate of less than 50°C per hour unreasonably increases the heat treatment time. Heating at above 60°C per hour leads to exceeding the tensile strength of the solid solution of chloride of silver bromide and cracking of the crystal. Heating to temperatures above 270°C does not lead to further reduction of internal stresses, but only increases the heat treatment of the crystal blank. The extract at a temperature of 250-270°C for 1-2 hours required for alignment and stabilization of the temperature gradient inside the treated crystal. When the cooling rate of 20 degrees per hour from 250-270°C up to 100-150°C in the crystalline workpiece under conditions of constant temperature gradient is not formed, residual stresses, because the crystal is in the temperature range exceeding the yield strength of the halides of silver, and the internal stresses are dispersed in the plastic flow. When the cooling rate is more than 25 degrees per hour occur in the crystal plastic deformation due to plastic displacement of the layers of the crystal, which upon further temperature reduction and the transition of the crystal in the region of elasticity arise in the form of internal elastic is their stress. Since the temperature of 100-150°C, the yield stress of solid solutions of the halides of silver reaches the value at which the crystal enters the region of elastic deformation. If this cooling rate can be increased up to 30-40°C per hour, as upon reaching room temperature, the elastic stress is dispersed to a value close to zero, due to the removal of the cooling temperature gradient. When the cooling rate is more than 40°C degrees per hour resulting thermoelastic stresses lead to cracking of the crystal blank. The cooling rate of less than 30°C per hour does not affect the formation of stress, but increases the duration of the process. Examples of the complete method. Example 1. Individual salts of chloride and bromide of silver, obtained by precipitation from a solution of nitrate of silver was subjected to purification from decomposition products, water and organic impurities by the method of filtration and vacuum distillation. Salt was loaded into the ampoule of heat-resistant glass "Pyrex" diameter 18 mm, the ratio (wt.%): 75% of AgBr and 25% AgCl (solid solution composition of cattle-13). The ampoule was vakuumirovat, filled halogenation atmosphere (pair chlorine) when the vapor pressure of the halogen 0,1atm and sealed. After melting salts and their mixing was performed directional crystallization method Bridgman stockburger without priming with what speed of 2 mm/hour. At the end of the growth process, the actuator moving the ampoule was stopped and lowered the temperature of the growing crystal with the speed of 10 degrees per hour to room. The crystal blank is removed from the ampoule, cut end, contaminated by impurities portion (~15% of the mass), was heated at 50 degrees per hour to a temperature of 250°C, kept for 1 hour to equalize the temperature within the furnace volume and cooled at a constant temperature gradient at a rate of 20 degrees per hour at first to a temperature of 150°C, and then with a speed of 30 degrees per hour to room. Part of the ingot after heat treatment used for the extrusion of the fibre. The extrusion of the fiber with a diameter of 500 μm was carried out at a temperature of 180°C with a speed of 15 mm/hour. The magnitude of the internal stresses and optical homogeneity of the crystal blanks controlled by measuring the birefringence value. The magnitude of birefringence in the workpiece after heat treatment amounted to 2.5 nm/see Coefficient of volume absorption of the crystal blank at a wavelength of 10.6 μm was 6·10-5cm-1. Optical loss in an optical fiber with a diameter of 0.5 mm, length 20 m 0.2-0.4 dB/m at a wavelength of 10.6 µm. Example 2. Individual salts of chloride and bromide of silver, obtained by precipitation from a solution of nitrate of silver was subjected to cleaning products according to the taxpayer, water and organic impurities by the method of filtration and vacuum distillation. Salt was loaded into the ampoule of heat-resistant glass "Pyrex" diameter 20 mm, the ratio (wt.%): 50% of AgBr and 50% AgCl (solid solution composition of CRS-11). The ampoule was vakuumirovat, filled halogenation atmosphere (pair chlorine) when the vapor pressure of the halogen of 0.15 ATM and sealed. After melting salts and their mixing was performed directional crystallization method Bridgman stockburger without priming with a speed of 3 mm/hour. At the end of the growth process, the actuator moving the ampoule was stopped and lowered the temperature of the growing crystal at a rate of 20 degrees per hour to room. The crystal blank is removed from the ampoule, cut end, contaminated by impurities portion (~20% mass), was heated at a speed of 60 degrees per hour to a temperature of 270°C, kept for 2 hours to equalize the temperature within the furnace volume and cooled at a constant temperature gradient at 25 degrees in the first hour to a temperature of 150°C, and then with a speed of 40 degrees per hour to room. Part of the ingot after heat treatment used for pre-forming blanks for shell fiber type core in the tube" (shell CRS-11 - core CRS-13). From this blank by extrusion at a temperature of 180°C with a speed of 15 mm/hour produced a fiber with a diameter of 700 μm is Lina 15 PM The magnitude of the internal stresses and optical homogeneity of the crystal blanks controlled by measuring the birefringence value. The magnitude of birefringence in the workpiece after heat treatment was 3.5 nm/see Coefficient of volume absorption of the crystal blank at a wavelength of 10.6 μm was 9·10-5cm-1. Optical loss in an optical fiber was at a wavelength of 10.6 µm 0.5 dB/m Thus, the claimed invention allows to increase flexibility, improve optical characteristics of the crystal blanks halides of silver: to reduce the coefficient of volume absorption and to reduce optical loss in an optical fiber by reducing the internal stress and thus increase the yield of fibers. The method of obtaining crystalline preparations of solid solutions of silver halides for optical elements, including downloading the source individual salts of chloride and bromide of silver in the container of heat-resistant glass, their fusion to a given composition of solid solution, the growing of the single crystal in the halogenation atmosphere by moving the container in a temperature gradient, the cooling of the grown crystal to room temperature and removing the crystal from the container, characterized in that grown monocrystal the l after cooling and removal from the container is heated with a speed of 50-60°C/h to a temperature of 250-270°C, maintained at this temperature for 1-2 hours, cooled at a rate of 20-25°C/h to a temperature of 100-150°C., then cooled with a speed of 30-40°C/h to room temperature.
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