972results about How to "Good optical performance" patented technology

The invention discloses a deterministic cutting compensation processing method for an infrared thin-wall optical element. The method comprises the following steps: S1, acquiring an initial surface shape of a workpiece; the method comprises the following steps: measuring an initial surface shape of a thin-wall optical element to be machined through an ultra-precision machine tool in-situ measurement technology to obtain a surface shape outline rho (x, y), and calculating a material removal amount deltaz (x, y) at each coordinate position according to a designed surface shape outline z (x, y), deltaz (x, y) = rho (x, y)-z (x, y); s2, elastic deformation prediction of clamping stress; based on a finite element simulation model, three-dimensional space numerical distribution simulation is conducted on clamping force distribution in the machining process, and element elastic deformation epsilon (x, y) caused by clamping stress is predicted; integrating the elastic deformation amount with the initial material removal amount to obtain a new material removal amount z '(x, y); s3, deformation prediction of the machining residual stress element; s4, generating a non-uniform material removal compensation track; and S5, non-uniform cutting compensation machining based on slow cutter servo is carried out.

The invention provides an optical lens and electronic equipment with the same, and the optical lens comprises a first lens which has negative focal power, the first side surface of the first lens is a convex surface, and the second side surface of the first lens is a concave surface; the second lens has negative focal power, the first side surface of the second lens is a concave surface, and the second side surface of the second lens is a convex surface; the third lens has positive focal power; the fourth lens has positive focal power; the fifth lens has positive focal power, and the first side surface and the second side surface of the fifth lens are convex surfaces; a sixth lens, wherein the sixth lens has negative focal power; a seventh lens, wherein the seventh lens has positive focal power; and the eighth lens has focal power, the first side surface of the eighth lens is a convex surface, and the second side surface of the eighth lens is a concave surface. According to the invention, at least one of the problems of difficulty in miniaturization, small field angle, poor imaging quality in a dark environment, poor temperature performance, serious aberration and poor light transmission capability of an optical lens in the prior art is solved.

The embodiment of the invention provides a projection system and optical display equipment. Wherein the projection system comprises a lens group, a prism and a display chip which are arranged in sequence; wherein the lens group is composed of a first lens, a second lens, a third lens and a fourth lens which are sequentially arranged, and the refractive index of the first lens, the refractive index of the second lens, the refractive index of the third lens and the refractive index of the fourth lens are larger than 1.6; the refractive index of the prism is less than 1.55; the projection system satisfies: 1 < = TTL / f < = 1.5; wherein TTL is the total optical length of the projection system, and f is the effective focal length of the projection system.

The invention relates to the technical field of flexible display devices, in particular to a high-impact-resistance coating for ultra-thin glass, a preparation method and an assembly layer. The invention discloses a high-impact-resistance coating for ultra-thin glass. The high-impact-resistance coating is mainly prepared from a precursor, a cross-linking agent and a photoinitiator in a solvent-free condition in a UV curing manner, the precursor comprises a polyether urethane acrylate oligomer with Tg of-70 DEG C to-40 DEG C; the Tg of the coating is 30-60 DEG C; and in a temperature scanning test with the temperature range of-40 to 80 DEG C and the frequency of 1Hz, the peak value of the loss factor of the coating is 0.7 to 1.2. The high-impact-resistance coating provided by the invention has good adhesion and excellent optical performance, also has good elongation at break and good flexibility, has a high dissipation effect on mechanical stress, and can enhance the impact resistance of the ultra-thin glass. In addition, the high-impact-resistance coating is prepared through a UV photocuring method and does not contain a solvent, the VOC emission in the production and preparation process is low, and the coating is green and efficient.

The invention provides a TEC control circuit for pump laser temperature control and a control method, and relates to the technical field of semiconductor cooler control. The control circuit comprises a temperature acquisition circuit, a differential amplification circuit, a PID (Proportion Integration Differentiation) control circuit, a TEC control signal generating circuit and a TEC driving circuit, the temperature acquisition circuit, the differential amplification circuit, the PID control circuit, the TEC control signal generating circuit and the TEC driving circuit are electrically connected in sequence, and the temperature acquisition circuit and the TEC driving circuit are respectively and electrically connected with the pump laser. According to the invention, the problem that the cost cannot be saved and the efficient, stable, reliable and accurate temperature change control cannot be carried out on the pump laser due to the limitation of several common modes for controlling the TEC in the practical application at present is solved.

The invention discloses a liquid crystal compound, a liquid crystal composition and a phase difference film, relates to the technical field of liquid crystal display, and aims to solve the problems of poor alignment order degree, low n value and low crosslinking completion degree in an existing liquid crystal system. The structural general formula (I) of the liquid crystal compound is set, and the liquid crystal compound is applied to the phase difference film. According to the liquid crystal compound, a long liquid crystal main chain is adopted, so that liquid crystal molecules are arranged more orderly, dense chromophoric group arrangement is achieved, Van der Waals force and hydrogen-bond interaction among the liquid crystal molecules are improved, the alignment order degree and the n value are improved, and the purposes of improving dispersion, lowering the manufacturing cost, lowering the film thickness requirement and improving the crosslinking completion degree are achieved.

The invention discloses a method for coating fluorescent powder with aluminum oxide through plasma-assisted atomic layer deposition, which comprises the following steps of: building an atomic layer deposition system, and placing a base station in a vacuum chamber of the atomic layer deposition system; fluorescent powder is placed on a base station, a vibration motor is turned on, and then the fluorescent powder is pretreated, including degassing treatment and oxygen plasma pretreatment; sequentially and alternately introducing two precursors into a vacuum chamber of the atomic layer deposition system, so that the two precursors are chemically adsorbed on the surface of the fluorescent powder and react to generate an aluminum oxide film; and after each precursor is introduced and reacts, the vacuum chamber needs to be cleaned by inert gas. According to the method, high-precision monoatomic-layer-level film control is achieved through the plasma-assisted atomic layer deposition technology, the defect that powder is prone to agglomeration in deposition is overcome through the vibration type fluidized bed technology, and therefore a high-quality aluminum oxide protection layer can be formed on the surface of the fluorescent powder; the water resistance and the luminescence property of the fluorescent powder are obviously improved.

The invention belongs to the field of polymeric membranes. The invention relates to a BOPLA (biaxially-oriented polylactic acid) film with high stretching ratio and a preparation method thereof. The packaging film comprises the following raw materials in parts by weight: 80-90 parts of PLA; 10 to 20 parts of PPC-P (Polypropylene Chloride-P); 10-15 parts of a plasticizer; 3.0 to 5.0 parts of a chain extender; 0.3 to 0.5 part of an antioxidant; 0.5 to 1.0 part of a lubricant; 0.1 to 0.3 part of an anti-hydrolysis agent; wherein the total mass of the PLA and the PPC-P is 100 parts; the preparation method comprises the following steps: mixing, extruding and plasticizing the raw materials according to the formula, and carrying out an asynchronous two-way stretching process, heat setting, traction, slitting and rolling. According to the present invention, the defects of mechanical property degradation and poor optical property of the PLA under the high stretching rate in the prior art can be effectively solved, and the great application potential is provided.

The invention relates to the technical field of chips, in particular to a reversed-polarity red light emitting LED chip and a manufacturing method thereof. The reversed-polarity red light emitting LED chip comprises a graphite substrate, a graphene bonding layer, an Ag reflector, an AZO conductive thin film layer, an MgF dielectric film layer, a GaP window layer, a P-type semiconductor layer, a light emitting layer, an N-type epitaxial limiting layer, an N-type current expansion layer, a coarsening layer, a passivation layer, a GaAs contact layer and an N electrode from bottom to top. According to the LED chip and the manufacturing method thereof, reasonable design is carried out on the chip manufacturing process, a mirror surface layer, a bonding layer, back gold and other metals do not need to be evaporated for multiple times, the chip manufacturing process is shortened, the use of chip gold can be greatly reduced, and the obtained LED chip is high in brightness, good in reliability, long in service life and low in cost.

The invention provides a chitosan-based hydrogel optical fiber material as well as a preparation method and application thereof, and belongs to the technical field of composite materials. Chitosan is modified by methacrylic anhydride to obtain a matrix solution of the hydrogel optical fiber, the reaction performance of the chitosan is enhanced, the modified chitosan and acrylamide are mixed, the mixture is irradiated by ultraviolet light to obtain the hydrogel fiber, then the hydrogel fiber is coated with a polyacrylamide solution, the chitosan with a high refractive index is used as a fiber core, and the hydrogel optical fiber is prepared. Acrylamide with excellent mechanical property is used as a coating layer, the problem of large light loss caused by insufficient refractive index of most of hydrogel is effectively avoided, the optical performance of the hydrogel optical fiber is improved, the prepared chitosan-based hydrogel is used as an optical fiber material, the biocompatibility and biodegradability of a brain-computer interface can be improved, and the application prospect is wide. The preparation method is simple and easy to operate.

The invention provides a high-water-resistance optical film and a polarizing plate comprising the same. The high-water-resistance optical film comprises a base film, a water-resistance layer and an adhesive layer, the structure of the high-water-resistance optical film comprises a water-resistance layer, a first adhesive layer, a base film and a second adhesive layer which are stacked in sequence, or the water-resistance layer, the base film and the second adhesive layer which are stacked in sequence, the surface of the waterproof layer is provided with nanometer protrusions and micropore structures which are uniformly and orderly arranged. The high-water-resistance optical film has excellent hydrophobicity, the water-resistance layer can efficiently absorb ultraviolet radiation, the problems of aging, yellowing, embrittlement and the like of the optical film caused by ultraviolet radiation are effectively prevented, the high-water-resistance optical film can be applied to a polarizing plate, and the service life of the polarizing plate is greatly prolonged.

The invention relates to the technical field of adaptive optics, and particularly provides a wavefront detection system for a dark and weak target under a strong sky background, the wavefront detection system comprises a Shack-Hartmann wavefront sensor system and a wavefront detection processing unit, the Shack-Hartmann wavefront sensor system carries out wavefront detection on a short wave infrared band of 1.3-1.7 [mu] m, and the wavefront detection processing unit carries out wavefront detection on the short wave infrared band of 1.3-1.7 [mu] m. And the wavefront detection processing unit corrects a sub-aperture image obtained by detection through a weighted self-threshold local contrast algorithm, performs self-threshold operation on pixels in a center unit according to a gray scale ratio weight of the center unit and a background unit of the sub-aperture image, introduces an energy weight to eliminate PNHB noise, and reconstructs a centroid of the sub-aperture image. According to the invention, a Shack-Hartmann wavefront sensor system is applied to a short-wave infrared band, so that a sky background spectrum is effectively blocked, the target brightness is ensured, background light radiation photons received by a detector are reduced to the greatest extent, various noises and background interferences are inhibited by optimizing a threshold algorithm, and the wavefront detection precision is remarkably improved.

The invention provides a hybrid passivation back contact battery and a preparation method thereof. The battery comprises a silicon wafer; a third tunneling oxide layer, a first amorphous silicon layer and a first anti-reflection layer are sequentially arranged on the front surface of the silicon wafer; first polishing areas and second polishing areas are alternately arranged on the back surface of the silicon wafer; a first semiconductor layer is at least arranged on the first polishing area; a second semiconductor layer is at least arranged on the second polishing area; a texturing area is arranged between the first polishing area and the adjacent second polishing area; a fourth tunneling oxide layer, a second amorphous silicon layer and a second antireflection layer are sequentially arranged on each of the first polishing region, the texturing region and the second polishing region; the refractive index of the first amorphous silicon layer is 2.2-4, and the refractive index of the first amorphous silicon layer is gradually reduced in the direction from the third tunneling oxide layer to the first anti-reflection layer. According to the invention, the passivation effect is improved, so that the battery efficiency is improved. In addition, the passivation layers on the front surface and the back surface can be deposited and formed in the same tubular PECVD, so that the process steps are simplified, and the equipment cost is reduced.

The invention discloses a multi-protection self-cleaning medical protective garment with a good antibacterial effect, and relates to the technical field of medical protective garments, the multi-protection self-cleaning medical protective garment comprises a protective hat, an upper garment and a lower garment, the protective hat, the upper garment and the lower garment are integrally formed and designed, and the protective hat, the upper garment and the lower garment are all of a multi-layer composite structure. The protective hat, the upper garment and the lower garment are integrally formed and designed, the problem of leakage at the joint is solved, the waterproof and antibacterial performance is guaranteed through the hydrophobic protective layer, the antibacterial isolation layer and the comfortable layer, the wearing comfort is also considered, meanwhile, organic silicon hydrophobic sol coated on the hydrophobic protective layer has the waterproof and antibacterial functions, and the waterproof and antibacterial effects are good. The self-cleaning effect of reducing stain attachment can be achieved, various protection requirements in the medical environment are met, the temperature and humidity change conditions of multiple parts in the protection suit are obtained in real time through the data acquisition module, the temperature and humidity in the protection suit are automatically regulated and controlled through the microprocessor module, and the protection suit is more intelligent. And the protection effect and the comfort of the protective clothing in use are improved.

The invention discloses a 35mm breathing-eliminating full-frame camera lens, and aims to solve the problems that in the prior art, when a visual angle is slightly enlarged or shrunk due to focus change, unnecessary jitter of a picture is caused, the fluency and ornamental value of a video are influenced, and the visual angle is slightly enlarged or shrunk. The lens comprises a variable diaphragm, and a first lens group, a second lens group and a third lens group which are sequentially arranged from an object side to an image side, the first lens group is composed of seven lenses and serves as a fixed group of the camera lens, and the focal power is positive; the iris diaphragm is located between the first lens group and the second lens group; the second lens group is composed of three lenses and serves as a focusing group of the camera lens, and the focal power is positive; the third lens group is composed of two lenses and serves as a fixed group of the camera lens, and the focal power is negative.

The invention relates to the technical field of optical fiber communication and optical measurement, in particular to an all-glass single-mode polarization-maintaining optical fiber collimator and a preparation method thereof.The all-glass single-mode polarization-maintaining optical fiber collimator comprises a collimating lens, a glass sleeve, a quartz ferrule and a single-mode polarization-maintaining optical fiber which are sequentially arranged along an optical path; the collimating lens and the glass sleeve are bonded and fixed through an oxyhydrogen catalytic bonding solution; an optical fiber core of the single-mode polarization maintaining optical fiber extends into the quartz ferrule, and one end of the quartz ferrule extends into the glass sleeve and is bonded and fixed with the glass sleeve through an oxyhydrogen catalytic bonding solution; the optical fiber collimator is prepared into a full-glass structure, stable collimation performance is ensured, meanwhile, the hydrogen-oxygen catalytic bonding technology is adopted for bonding and fixing all parts of the optical fiber collimator, high-strength and glue-free bonding can be achieved, the problem of thermal instability caused by poor thermal conductivity is effectively avoided, and long-term stable optical performance is ensured.

In order to solve the problems that in the prior art, in the laser coating preparation process, high-temperature mold pressing is needed due to the high softening point of matrix resin, and the requirements for the technology and equipment are high, the laser transfer coating comprises the matrix resin, and the matrix resin comprises an acrylate monomer and a first functional monomer; the first functional monomer is prepared from one or more of o-phenyl phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, ethoxylated bisphenol A diacrylate, propoxylated bisphenol A diacrylate and 4-biphenylmethanol acrylate, and the second functional monomer is prepared from one or more of o-phenyl phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, ethoxylated bisphenol A diacrylate, propoxylated bisphenol A diacrylate and 4-biphenylmethanol acrylate; the matrix resin further comprises a second functional monomer, and the second functional monomer comprises an unsaturated monomer containing a heterocyclic side group or a polar group. According to the laser transfer coating provided by the invention, after the acrylate monomer and the first functional monomer are combined, not only is good film-forming property provided for the coating, but also the coating has relatively good optical property, reflection and refraction of light can be regulated and controlled on a microscopic level, and the visual effect of coating of the laser transfer coating is enhanced.

The invention relates to the technical field of time delay imaging, in particular to a scintillator capable of being used for time delay imaging, a preparation method and application. The invention aims to solve the technical problems of the traditional time delay imaging scintillator in the aspects of use environment, delay time and imaging resolution, and realize high-efficiency, high-stability, long-time delay and high-spatial resolution imaging. According to the main scheme, the coated lanthanum element doped fluoride nanocrystalline scintillator is characterized in that a coating layer comprises inorganic glass, organic glass and silicon dioxide, the lanthanum element comprises any one of Tb, Eu, Er, Ce, Ce / Tb, Gd / Tb and Ce / Tb / Gd, and fluoride nanocrystalline is any one of Pb4Lu3F17, Pb4Lu3F17, Pb4Lu3F17, Na5Lu9F32, Cs0. 02Na0. 98LuF4 and Ba2LaF7. According to the invention, not only is long-time imaging after X-ray radiation realized, but also high-spatial-resolution imaging after time delay is realized, and the method is suitable for the fields of industrial detection, medical imaging and the like.

A composite structure hollow anti-resonance optical fiber disclosed by the present invention comprises an outer cladding layer, a doping layer and an anti-resonance layer which are sequentially arranged from outside to inside, the anti-resonance layer comprises a plurality of glass nested combination tubes which are uniformly distributed along the circumferential direction, are tangent to the doping layer and are arranged at intervals, and the plurality of glass nested combination tubes surround to form an air fiber core. The glass nested combined pipe comprises an outer nested pipe of a circular structure and an inner nested pipe of an oval structure arranged in the outer nested pipe. The short half axis of the inner nested pipe is arranged in the radial direction of the optical fiber, and the outer ring, away from the air fiber core, of the inner nested pipe is tangent to the inner ring, away from the air fiber core, of the outer nested pipe. According to the invention, a multi-layer nested structure is adopted, and the anti-resonance effect is optimized through the cooperation of the doping layer and the anti-resonance layer with a special structure.

The invention discloses a 6H scratch-resistant acrylic plate as well as a preparation method and application thereof, and belongs to the technical field of high polymer materials. The acrylic plate comprises a first hardening coating, a PMMA (polymethyl methacrylate) layer and a second hardening coating from top to bottom. The scratch-resistant acrylic plate provided by the invention adopts an innovative hard liquid composition, and comprises polyurethane acrylic resin, an active monomer, metal oxide nanoparticles, a photoinitiator and an auxiliary agent. Compared with an existing scratch-resistant coating material, the scratch-resistant coating material has the advantages that the polyurethane acrylic resin is used as a main film forming substance and is combined with the active monomer and the photoinitiator, so that a high-hardness coating can be quickly formed under a photocuring condition, the formula of the coating is simplified, and the wear resistance, the toughness and the optical performance of the coating are effectively improved; the composition avoids dependence on traditional hardeners and solvents, reduces emission of volatile organic compounds, and is more environment-friendly.

The invention relates to the technical field of automobile data recorders, in particular to an automobile data recorder, which is characterized in that an automatic adjustment lens structure allows the automobile data recorder to perform real-time adjustment according to different illumination and environmental conditions, and can provide optimal visual angle setting in various driving scenes; wherein the design structure of the camera module avoids a common high distortion phenomenon in a traditional lens; by reasonably configuring the shape and the refractive index of the lens, the geometric integrity of an image can be kept under a large visual angle, so that shot sceneries and objects are not distorted, meanwhile, a non-gluing design is adopted, performance reduction caused by environmental changes (such as temperature and humidity) is avoided, the lens can still keep stable optical performance and image quality under different use conditions, and the lens can be widely applied to the field of camera shooting. The problems of aging and optical degradation possibly occurring in long-time use of the glued lens are solved.

An optical lens provided by the present invention comprises a lens barrel, and a lens group and a spacer element group which are assembled in the lens barrel, the spacer element group at least comprises a first spacer element and a second spacer element, the first spacer element is located between a first lens and a second lens and is in partial contact with the image side surface of the first lens, and the second spacer element is located between the second lens and the second lens. The second spacing element is positioned between the second lens and the third lens and is in contact with the image side surface part of the second lens; the maximum height L of the lens cone and the effective focal length f of the optical lens meet the following conditions: 2.44 lt; l / flt; 3.15, 3.15; the effective focal length f2 of the second lens, the spacing distance EP12 between the first spacing element and the second spacing element in the direction of the optical axis, and the center thickness CT2 of the second lens meet the following conditions: 2.90 mm <-1 > lt; (CT2 / EP12) / f2lt; 6.56 mm <-1 >. According to the invention, the problem that miniaturization and assembly stability of an optical lens in the prior art are difficult to consider at the same time is solved.

The invention discloses a PP resin foaming optical diffusion plate and a preparation method thereof.The diffusion plate comprises an upper layer, a middle layer and a lower layer, the upper layer and the lower layer are located on the two sides of the middle layer, the thickness ratio of the upper layer to the middle layer to the lower layer is 1: (7-9): 1, and the upper layer and the lower layer are the same in composition; the upper layer is prepared from the following components in parts by mass: PP resin, PP-g-MAH resin, copolymer microspheres, a flame retardant, an antioxidant, mineral oil, a light stabilizer, an ultraviolet light absorber and a whitening agent; the middle layer is prepared from the following components in parts by mass: GPPS resin, a foaming agent, an antioxidant, mineral oil, a light stabilizer, an ultraviolet light absorber and a whitening agent, and the diffusion plate is stable in overall structure, good in optical performance and low in manufacturing cost.

The invention discloses low-lithium high-strength transparent microcrystalline glass and a preparation method thereof. The low-lithium high-strength transparent microcrystalline glass is prepared from the following raw materials: 7wt%-15wt% of Li2O, 2wt%-12wt% of Al2O3, 60wt%-78wt% of SiO2, 1wt%-4wt% of ZrO2, 1wt%-5wt% of P2O5, 0-1wt% of Na2O and 0-3wt% of K2O. The preparation method comprises the following steps: mixing the raw materials, melting, annealing and crystallizing to obtain the low-lithium high-strength transparent glass ceramic which is a glass ceramic product with high mechanical strength, high transmittance, low haze, low dielectric loss and high thermal conductivity, can meet the requirements of mobile phone cover plate glass on the glass ceramic, reduces the cost, has a very good market value, and is suitable for popularization and application. The high-strength transparent microcrystalline glass can be applied to a front cover and / or rear cover protection component in a cover plate material for a touch display product.

The invention discloses selenium-containing unsaturated polyesteramide and a preparation method thereof, and the preparation method comprises the following steps: mixing and dissolving a diamine compound, propiolic acid ester and selenolactone in an organic solvent, and carrying out chemical reaction to obtain the selenium-containing unsaturated polyesteramide. A diamine compound, propiolic acid ester and selenolactone are used as raw materials, selenium-containing unsaturated polyesteramide is generated through click polymerization reaction of selenol and alkyne, the novel preparation method of selenium-containing unsaturated polyesteramide is developed, and the prepared polyesteramide is narrow in molecular weight distribution, controllable in structure and adjustable in degradation rate, and can be used for preparing selenium-containing unsaturated polyesteramide. Long-term stability is good, multiple responsiveness is achieved, and optical performance is good; the raw materials are wide in source, tedious substrate synthesis is avoided, the steps are simple, the reaction conditions are mild, the polymerization speed is high, and efficient large-scale production can be achieved; no catalyst is needed, no by-product is generated, and extra purification is not needed.

The invention discloses a preparation method of a flexible magneto-optical composite material which is low in cost and easy to form, Fe3O4 or CoFe2O4 or NiFe2O4 nanoparticles which have a strong magneto-optical effect but are extremely easy to agglomerate are uniformly dispersed in ZIF-8 with fixed pores by adopting an in-situ symbiosis technology, and PgC5Cu is used for modifying the surface of the ZIF-8 to serve as a bridging agent, so that the ZIF-8 is uniformly dispersed in PMMA (Polymethyl Methacrylate); and the composite material with excellent magneto-optical characteristics is successfully constructed. The innovative design not only maintains the original structural stability and optical transparency of the material, but also endows the material with unprecedented flexibility and machinability, and provides possibility for realizing light weight, portability and flexibility of magneto-optical devices. Compared with traditional pure inorganic magneto-optical crystals, magneto-optical glass and other materials, the preparation method is simple, the production period is short, energy consumption and cost are remarkably reduced, and the material has the advantages of being easy to form, high in flexibility and the like and can adapt to wider application scenes.

The invention provides a flexible transparent polyimide film and a preparation method thereof, and relates to the technical field of high polymer materials. The polyimide film is prepared from diamine and dianhydride through a polymerization reaction. The diamine comprises a first diamine and a second diamine; the first diamine is aromatic diamine containing a rigid group; the second diamine is diamine containing imidazole; the dianhydride comprises first dianhydride and second dianhydride; the first dianhydride is selected from at least one of 3, 3, 4, 4-diphenyl sulfone tetracarboxylic dianhydride, 4, 4 '-biphenyl tetracarboxylic dianhydride and benzophenone tetracarboxylic dianhydride; and the second dianhydride is selected from 2, 2 '-(1, 4-piperazine diacyl)-succinic anhydride or 2R, 5R, 7S, 10S-naphthalene tetracarboxylic dianhydride. According to the polyimide film prepared by the method, the optical performance is remarkably improved, and meanwhile, better heat resistance and mechanical performance are obtained.

The invention provides a preparation method of microcrystalline glass, chemically strengthened microcrystalline glass and a microcrystalline glass product, and relates to the technical field of materials, the crystalline phase of the microcrystalline glass comprises petalite, lithium disilicate and lithium silicate, and the crystallinity is less than or equal to 90%; the ratio of the content of petalite to the content of total crystals is 45-60%, the ratio of the content of lithium disilicate to the content of total crystals is 30-45%, the ratio of the content of lithium silicate to the content of total crystals is less than or equal to 13%, and the ratio of the total content of petalite and lithium disilicate to the content of total crystals is greater than or equal to 75%. Through the implementation of the application, the contents and crystal sizes of different crystal phases are controlled at a specific ratio, so that the glass ceramic product can be ensured to have excellent optical performance while having good mechanical strength performance.

The invention relates to a hydrochromic flexible intelligent thin film and a preparation method thereof. The hydrochromic flexible intelligent thin film can be used for preparing a passive driving flexible intelligent hydrochromic thin film (such as a window thin film). The method comprises the following steps: uniformly doping mesoporous microspheres modified by nano-sized hydrophilic groups into a polymer, curing, and carrying out hydrophilic treatment by using a polyethyleneimine aqueous solution to form the polymer / nano-microsphere composite film. Under different humidity conditions, water absorption / water loss is achieved, the refractive index is changed, the light transmittance of the material is correspondingly changed, incident illumination can be effectively enhanced / weakened through the light transmittance change responded by humidity, and the purpose of photo-thermal regulation and control is achieved. The preparation method is simple, and large-area production can be realized. The polymer / nano microsphere intelligent thin film has good self-regulation optical performance, high response speed, good mechanical performance, thermal stability and corrosion resistance, and the thin film has wide application potential in the scenes of buildings, greenhouses and the like as a passive driving flexible intelligent window.

The invention relates to the technical field of liquid silicone rubber, in particular to high-refractive-index low-haze addition type liquid silicone rubber and a preparation method thereof, and the high-refractive-index low-haze addition type liquid silicone rubber is prepared from vinyl silicone oil, a catalyst, an inhibitor, a cross-linking agent, hydrophobic white carbon black, a white carbon black surface treating agent and the like. According to the method, by regulating and controlling the surface state of the white carbon black and the refractive index of the silicone oil, the addition type liquid silicone rubber with high refractive index, high light transmittance and low haze at the same time is realized, and the addition type liquid silicone rubber is good in mechanical property and fluidity, can adapt to continuous extrusion production, and is suitable for large-scale production. After vulcanization, the Shore A hardness is 50-53, the light transmittance is 94% or above, the haze is lower than 3%, the refractive index reaches 1.54 or above, and the polyurethane resin can be applied to the fields of optical devices, LED packaging and the like.