73results about How to "Increase the refractive index difference" patented technology

The invention discloses an optical waveguide, a method for preparing the same and a wavelength converter. The cross section of the optical waveguide is in a shape like a Chinese character 'tu'; a waveguide layer of a near-stoichiometric doped lithium niobate crystal with a poled chirp period is positioned on the upper layer of the optical waveguide, and is bonded with a lower substrate by a film of which the middle contains Si components. The embodiment of the invention improves the refractivity difference between the substrate and the waveguide layer, restrains the transmission of an opticalsignal in the optical waveguide and improves the conversion efficiency through film coating, widens pump bandwidth through the grating structure with the poled chirp period, reduces the photoinduced absorption effect under the irradiation of high-strong lasers and improves the conversion efficiency by adopting the waveguide layer of the near-stoichiometric doped lithium niobate crystal.

The present invention relates to a gradient index progressive addition spectacle lens that provides improved optical performance and a wide visual field. The lens comprises a plurality of axially layered and bonded lens sections of continuous curvature at least one of which has a refractive index gradient oriented transverse to a meridian of the lens that functions as a progressive intermediate vision zone between viewing portions of different refractive index that provide the refractive powers for corresponding vision portions of the lens. The other layer(s) of the lens incorporates a generally constant or similarly changing refractive index.

Provided is a light diffusing element that has a high haze value and strong diffusion characteristics with limited backscatter, and can be produced at a low cost. The light diffusing element has a matrix that includes a resin component and an ultra-fine particle component, and light diffusing micro particles dispersed within said matrix, wherein said resin component, said ultra-fine particle component, and said light diffusing micro particles fulfill the conditions of a formula (1) below, and has a concentration adjusted area that is formed near the interface of said matrix and said light diffusing micro particles wherein the weight concentration of said resin component becomes progressively lower and the weight concentration of said ultra-fine particle component becomes progressively higher with distance from said light diffusing particles. (1) |nP-nA|P-nB| In formula (1), nA represents the refractive index of the resin component in the matrix, nB represents the refractive index of the ultra-fine particle component in the matrix, and nP represents the refractive index of the light diffusing micro particles.

The present invention provides an optical element which can reliably acquire a difference of refractive indices between a member under a photonic crystal layer and the crystal layer without using such a stacking technique as in conventional processes; a method for manufacturing the optical element; and a semiconductor laser device with the use of the optical element. The optical element has the first layer 500 and the second layer 400 formed on a substrate 100, wherein the second layer includes pores and has a refractive-index periodically changing structure in which a refractive index periodically changes in an in-plane direction; and the first layer has an oxidized region with a lower refractive index than the refractive index of the second layer, in a lower side of the pores of the second layer.

A GaN-based laser with asymmetric Al component AlGaN limiting layers comprises a GaN native substrate, an n-type GaN homoepitaxial layer, the n-type AlGaN limiting layer, an n-type GaN waveguide layer, an InGaN / lGaN quantum well active region, a p-type AlGaN electron blocking layer, a p-type GaN waveguide layer, the p-type AlGaN limiting layer, a p-type doped / p-type heavily-doped contact layer, a p-type ohmic electrode and an n-type ohmic electrode. The n-type GaN homoepitaxial layer is manufactured on the GaN native substrate, the n-type AlGaN limiting layer is manufactured on the n-type GaN homoepitaxial layer, the n-type GaN waveguide layer is manufactured on the n-type AlGaN limiting layer, the InGaN / lGaN quantum well active region is manufactured on the n-type GaN waveguide layer, the p-type AlGaN electron blocking layer is manufactured on the InGaN / lGaN quantum well active region, the p-type GaN waveguide layer is manufactured on the p-type AlGaN electron blocking layer, the p-type AlGaN limiting layer is manufactured on the p-type GaN waveguide layer, a protruding ridge is formed in the middle of the p-type AlGaN limiting layer, the p-type doped / p-type heavily-doped contact layer is manufactured on the protruding ridge of the p-type AlGaN limiting layer, the p-type ohmic electrode is manufactured on the p-type doped / p-type heavily-doped contact layer, and the n-type ohmic electrode is manufactured on the lower surface of the GaN native substrate.

The invention relates to a photonic crystal structure chromogenic fabric and a preparation method thereof, and belongs to the field of photonic crystal structure chromogenesis. The preparation methodof the photonic crystal structure chromogenic fabric comprises the following steps that (1), dispersion liquid of photonic crystal structure primitive nano microspheres is prepared, a photonic crystalstructure is constructed on the surface of a textile base material, and the photonic crystal structure chromogenic fabric is obtained; (2), an encapsulant solution is prepared, and the surface of thephotonic crystal structure chromogenic fabric is coated with the encapsulant solution, the mass fraction of an encapsulant in the encapsulant solution is 0.1-10%, and the encapsulant is selected fromone or a mixture of more of waterborne polyurethane, waterborne acrylate, waterborne urethane acrylate or waterborne organic silicon; and (3), the photonic crystal structure chromogenic fabric obtained in the step (2) is dried and cured in a drying device to obtain the photonic crystal structure chromogenic fabric.

A known refraction-sensitive optical fiber comprises a core zone with an index of refraction nK, a jacket zone surrounding the core zone, said jacket zone having an index of refraction nM, and an annular zone made of quartz glass doped with fluorine, said annular zone surrounding the jacket zone and having an index of refraction NF, where nF<nM<nK. With this as a starting point, an optical fiber is to be provided that is characterized by high refraction-sensitivity, good spliceability and compatibility, and a method is to be provided for cost-effective manufacture of such a fiber. With regard to the method, this object is accomplished according to the invention in that the quartz glass of the annular zone (21) is produced in a plasma deposition process on the outside in which an annular zonal layer made of the quartz glass doped with fluorine is produced on a substrate body (20), said layer having a layer thickness of at least 1 mm and an index of refraction nF<1.4519 relative to the D line of the sodium vapor lamp.

A process for producing a light-diffusing element is provided by which a light-diffusing element having a high haze and high diffusing properties and reduced in backward scattering can be produced at low cost with high productivity. The process for producing a light-diffusing element comprises a step in which a matrix-forming material comprising a resin-ingredient precursor and an ultrafine-particle ingredient is brought into contact with fine light-diffusing particles, a step in which at least some of the precursor is infiltrated into an inner part of the fine light-diffusing particles, and a step in which the precursor that has infiltrated into the inner part of the fine light-diffusing particles and the precursor that has not infiltrated into the fine light-diffusing particles are simultaneously polymerized to form a matrix comprising the resin ingredient and the ultrafine-particle ingredient and simultaneously form a concentration gradation region in the vicinity of the inner side of the surface of the fine light-diffusing particles.

The invention discloses a non-volatile tunable directional coupler based on a phase change material. The coupler comprises an SOI substrate, the SOI substrate is provided with a parallelly distributedinput silicon waveguide and an output silicon waveguide in a horizontal direction, the coupler is characterized in that the upper surface of an output silicon waveguide is provided with a phase change material GST waveguide layer in the length direction, the GST waveguide layer is located in the coupling region and is uniformly divided into N segments, each segment can work in a crystalline or amorphous state, the N is any natural number within 3-20, the coupler achieves any ratio of power coupling by changing the number of segments of the GST waveguide layer in crystalline and amorphous state, and the coupler has the advantages of on-chip integration, low energy consumption, wide operating bandwidth, low insertion loss and the tunable output power.

A nitride semiconductor laser element includes a substrate and a nitride semiconductor layer in which a first semiconductor layer, an active layer, and a second semiconductor layer are laminated in this order on the substrate. At least one of the first semiconductor layer and the second semiconductor layer includes a first section forming recessed and raised portions and a second section embedding the recessed and raised portions of the first section. A region with a higher aluminum mixed crystal ratio than the second section that embeds the recessed and raised portions is disposed on top faces of the raised portions. The nitride semiconductor layer defines resonant planes, and the recessed and raised portions are formed in a shape of stripes that extend substantially parallel to the resonant planes.

The invention discloses a self-assembly of a brush-shaped block polymer containing PEG segments as well as a synthesis method and application of the self-assembly. According to the self-assembly material, the PEG is introduced into the brush-shaped block polymer, and the one-dimensional photonic crystal with bright structural color is prepared through melting self-assembly and cooling limited crystallization, so that the refractive index difference of two sections of the brush-shaped block polymer is effectively improved, the preparation process of the one-dimensional photonic crystal is simplified to a great extent, and the long-wavelength one-dimensional photonic crystal is prepared under the condition that the polymerization degree of a main chain is small. In the process of preparing the one-dimensional photonic crystal, through melting self-assembly and cooling limited crystallization, compared with solvent evaporation self-assembly, the controllability is higher, and the method is easy and convenient to operate, fast to assemble and low in cost. The prepared one-dimensional photonic crystal has good temperature response, thermal repair, pattern splicing and other properties,and has huge application prospects in the aspects of information counterfeiting prevention, thermal sensing, melt spinning, 3D printing, silk-screen printing, functional coatings, optical fibers and the like.

Disclosed is a novel wide-angle lens for an endoscope, wherein an object lens of the novel wide-angle lens includes a combination of a uniform plano-convex lens and a Grin lens, and the view angle of the lens is widened by increasing the difference between refractive indexes of the lens center and the lens periphery. The Grin lens is adopted at the lens center while the uniform plano-convex lens is adopted at the periphery from one to two apertures, the refractive index of the uniform plano-convex lens is smaller than the smallest refractive index of the Grin lens, and the periphery of the lens is manufactured non-transparently, thereby preventing stray light generated by light reflecting on the sides of the lens.

The invention discloses a polarization controller based on an X-cut thin film lithium niobate waveguide. The polarization controller comprises a first phase shift region, a mode conversion region, a second phase shift region and a bent waveguide, wherein one end of the first phase shift region is an input end, and the other end is connected with one end of the mode conversion region through the bent waveguide; the first phase shift region and the second phase shift region are composed of lithium niobate straight waveguides which are not subjected to polarization reversal, bent waveguides, lithium niobate straight waveguides which are subjected to polarization reversal and electrodes, the straight waveguides are arranged in the Y direction of a lithium niobate crystal axis, and the electrodes are located on the left side and the right side of the straight waveguides; the other end of the mode conversion region is connected with one end of the second phase shift region through the bent waveguide; the other end of the second phase shift region is an output end for outputting light of the polarization controller; the mode conversion region is composed of a lithium niobate straight waveguide, a bent waveguide and electrodes, and the electrodes are located around the straight waveguide; and the first and second phase shift regions realize a push-pull working mode through polarization reversal part lithium niobate waveguides. The controller has the advantages of high speed, high precision, small size and easiness in integration.

The invention discloses a flexible film random laser device adjustable in polarization degree and a preparation method thereof. The random laser device is of a film-shaped structure and is prepared from polyvinyl alcohol, polyalcohol and dye nematic-phase liquid crystal micro-droplets, wherein the polyalcohol and the dye nematic-phase liquid crystal micro-droplets are located in a film prepared from the polyvinyl alcohol. The flexible film random laser device changes orientation of nematic-phase liquid crystal molecules in the polyvinyl alcohol film and achieves random laser emergence adjustable in polarization degree by mechanically stretching the polyvinyl alcohol film containing the dye nematic-phase liquid crystal micro-droplets under the condition of laser pumping based on optical anisotropy of nematic-phase liquid crystal, and the random laser polarization direction is parallel to the stretching direction. The flexible film random laser device can achieve the functions of random laser wavelength stabilization and continuous and adjustable polarization degree, has the advantages of being low in cost, simple in structure, convenient to achieve and the like and has the better application value on the aspects of laboratory polarization calibration, system-level performance detection and the like of displays, sensors and polarizing optical remote sensors.

The invention discloses a vertical cavity surface emitting laser and a preparation method thereof. The preparation method of the vertical cavity surface emitting laser comprises the steps: a first DBRlayer and a second DBR layer are formed on a first substrate and a second substrate by a magnetron sputtering method, and a light emitting layer is formed on the second DBR layer by spin coating. Theproblem that the lattice matching between the film layers needs to be considered when preparing the DBR layer and the light emitting layer by epitaxial growth can be avoided so that the materials used for preparing the first DBR layer and the second DBR layer are not limited by lattice matching, the refractive index difference between the two dielectric layers forming the first DBR layer and thesecond DBR layer can be increased, the first DBR layer and the second DBR layer can have high reflectivity only by fewer film layers, the preparation process of the device is reduced, and thus the preparation period and the preparation cost of the device can be reduced and the preparation efficiency of the device can be improved.

The invention relates to a camera shooting method and device of a day and night lens without an IR-Cut (infrared-cut) switcher. An optical light-transmitting element in front of, in the middle of or behind the lens is plated with a filter coating, or the optical light-transmitting element provided with the film coating is additionally arranged in front of, in the middle of or behind the lens; the filter coating has the characteristics that transmittance of light with the wavelength of 400-640 nm or 840-970 nm is increased, the average transmittance of the light with the wavelength of 400-640 nm or 840-970 nm is higher than 98%, light with the wavelength of 670-800 nm is cut off and the average transmittance of the light with the wavelength of 670-800 nm is lower than 0.4%; moreover, a color correction unit with functions of separating and eliminating infrared component signals in image signals is additionally arranged in an image signal processor connected with an image sensor. The method and the device can radically solve a problem of slight red images shot by a camera at day time without the IR-Cut switcher, truly realize day and night use of the lens, and can guarantee that the lens is reliably used.

Provided is a light-diffusing adhesive that can achieve an image display device having superior visibility without the occurrence of corner unevenness even in high-temperature environments. The light-diffusing adhesive includes: an adhesive containing a base polymer containing a (meth)acrylate polymer; and light-diffusing microparticles having a refractive index lower than that of the adhesive. The (meth)acrylate polymer contains an aromatic ring-containing (meth)acrylate monomer as the monomer unit.

The invention provides a layered doped step type weak coupling gain equalization four-mode erbium-doped optical fiber. The refractive indexes of the fiber core and the cladding of the optical fiber are integrally kept in a step type, the fiber core part is two or more layers of concentric circles which are adjacent in sequence, and the erbium-doped concentrations of the layers are different. The part with insufficient refractive index or surplus of each layer is supplemented or eliminated through co-doped elements. According to the optical fiber, under the condition that the number of modes isclose to that of transmission optical fibers, the mode gain difference is effectively reduced, and the good mode gain equalization characteristic is achieved. Meanwhile, due to the proper selection of the refractive index and radius of the optical fiber, the refractive index difference between the modes is large, the mode crosstalk is effectively reduced, and the application in optical communication and optical wavelength division multiplexing systems is facilitated.

A method for preparing silica wave guide with high refractivity difference by using ultraviolet layer write ¿C in includes forming substrate by growing silica bottom cladded, wave guide layer and top cladded in sequence on silicon or silica backing; loading hydrogen on said substrate; carrying out uniform exposure for substrate with ultraviolet laser to rise refractivity on wave guide layer uniformly; preparing mask and hollowing out its nonwaveguide region; covering wave guide region by mask and carrying out second time of exposure to lower refractivity at uncovered region; annealing for stabilizing refractivity variation.

The invention is applicable to the fields of optical fiber sensing, an optical fiber gyro, optical fiber communication and the like, and provides an ASE light source which comprises a wavelength division multiplexer, a pump laser connected with an input end of the wavelength division multiplexer, a first opto-isolator connected with a second output end of the wavelength division multiplexer, and a photonic crystal optical fiber connected with a first output end of the wavelength division multiplexer, wherein the photonic crystal optical fiber further comprises a fiber core and a cladding layer used for covering the fiber core; and the cladding layer is provided with a shaddock-shaped air vent hole. By adopting the photonic crystal optical fiber provided with the shaddock-shaped air vent hole, the ASE light source reduces the effective refractive index of the cladding layer so as to lead greater refractive index difference to be formed between the fiber core and the cladding layer, has stronger constraint capability for electromagnetic field, reduces the bending loss and decreases the size of an optical fiber light source.

A method of making a photonic crystal includes step 1 providing a seed, followed by etching a surface of the seed to form thereon submicron voids; step 2 providing a graphite disk, followed by coating a side of the graphite disk with a graphite adhesive whereby the void-formed surface of the seed is attached to the graphite disk to form a seed holder; step 3 placing the seed holder above a growth chamber, followed by placing a raw material below the growth chamber; step 4 forming a thermal field in the growth chamber with a heating device to sublime the raw material; and step 5 controlling temperature, thermal field, atmosphere and pressure in the growth chamber to allow the gaseous raw material to be conveyed and deposited on the seed, thereby forming a photonic crystal.

The invention discloses a DBR low refractive index layer etching method for reducing the number of DBR cycles. An ion beam etching method is applied to perform mesoporous etching on the low refractiveindex layer in the DBR layer of a vertical cavity surface emitting laser so as to improve the refractive index difference between the combined two DBR layers. The method is simple in operation and accurate in control and can ensure the size and the accuracy of the obtained mesopore, can realize high reflectivity and can reduce the cycle number of the DBR. In the preparation process of the nano-array device, the focused ion beam etching equipment is applied to perform direct selective etching of the chip. Compared with the dry etching technology, the advantages of the focused ion beam etchingequipment are utilized to reduce the deposition of the protective layer, which can avoid the damage caused by poor accuracy of dry etching, and the radiation damage caused by ion beam etching can alsobe removed by wet etching. The method is simple and controllable and can ensure the size and the accuracy of the obtained mesopore so as to realize DBR with high reflectivity and low cycle number.

The invention discloses a dual-channel filter and method for preparing dual-channel filter by spin-coating blue dye. The filter comprises a glass substrate, a blue dye layer arranged on the surface of one side of the glass substrate, an adhesion layer arranged on the blue dye layer, an ultra wide band reflection film arranged on the adhesion layer and a dual-channel filtering sheet arranged on the surface of the other side of the glass substrate. The method comprises steps of coating the glass substrate with the blue dye layer by use of the spin-coating method; by using the vacuum plating method and combining low-energy ions, carrying out auxiliary deposition on the adhesion layer; and by using the vacuum plating method and combining high-energy ions, carrying out auxiliary deposition on the ultra wide band reflection film and the dual-channel filtering sheet. According to the invention, the glass substrate spin-coated with the dye layer and the dual-channel filter have wide application prospects in the field of mobile phone shooting systems, and security television systems.

The invention relates to the field of pigments, specifically to a silver pearlescent pigment and a preparation method and application thereof. The pigment comprises a pigment substrate, and a titaniumdioxide inner layer, an aggregated oxide layer with a silica skeleton structure and a titanium dioxide outer layer which sequentially coat the pigment substrate in a heating hydrolysis manner, wherein the aggregated oxide layer with the silica skeleton structure is formed by hydrolytic condensation of siloxane and has a hollow structure. According to the silver pearlescent pigment provided by theinvention, a multi-layer coating structure with alternate high and low refractive indexes is formed, so the brightness of the pearlescent pigment can be effectively improved; the aggregated oxide layer has the hollow structure, so a refractive index is reduced, and a larger refractive index difference exists between layers, which enables the glossiness of a product to be improved and covering power to be enhanced; besides, the titanium dioxide inner layer, the aggregated oxide layer and the titanium dioxide outer layer realize coating in a heating hydrolysis manner, so a coating process is simplified, a pH value does not need to be adjusted, control is convenient, and product quality is more stable and reliable.

The invention discloses a thin fiber and a manufacture method of the thin fiber. The thin fiber comprises a diamond fiber core which comprises a strengthened fiber. A silica covering layer is arranged on the outer surface of the diamond fiber core. A coating layer is arranged on the outer surface of the silica covering layer. The diamond fiber core is a concrete or hollow fiber which is made of diamond. The manufacture method of the thin fiber includes the following steps. A fiber segment is arranged in a sealed container, pure methane gas and hydrogen are introduced into the sealed container. A radio frequency device or a microwave device is used for heating the gas in the sealed container so that an ionic state appears in the sealed container and lasts for at least five minutes until a diamond film or a diamond-like film is deposited on the surface of the fiber. A silica film is plated on the diamond film or the diamond-like film so as to obtain the thin fiber. The thin fiber has the advantages of being even in outer diameter, high in strength, simple in manufacture method, low in cost and good in application prospect.

The invention provides a preparation method of a variable iridescent liquid crystal photonic crystal material. The preparation method comprises the following steps: (1) mixing ethanol, water and a dispersing agent, and heating; (2) mixing a polymerizable monomer, a cross-linking agent, a liquid crystal monomer and a photoinitiator; (3) mixing the mixture obtained in the step (2) with the mixture obtained in the step (1); (4) mixing the mixture obtained in the step (3) with a polymerization initiator, irradiating with an ultraviolet lamp, keeping at 70-100 DEG C under nitrogen for 3-9 hours, and carrying out freeze drying to obtain colloidal microsphere powder; (5) completely converting the colloidal microsphere powder obtained in the step (4) into a molten state; (6) carrying out hot pressmolding on the material obtained in the step (5), and then cooling; and (7) performing solvent etching and air drying on the material obtained in the step (6) to obtain the variable iridescent liquidcrystal photonic crystal material. The liquid crystal photonic crystal material has the advantages of variable iridescent color, good mechanical properties, controllable thickness and easy expansionand extension preparation of the three-dimensional size.

The invention discloses a display panel and an electronic device. The display panel includes a substrate; a display layer which is arranged on the substrate and comprises a plurality of light-emitting units; a touch layer which is arranged at the side, away from the substrate, of the display layer and comprises a first insulating layer, a touch electrode layer and a second insulating layer which are sequentially stacked, wherein the touch electrode layer comprises a plurality of touch electrodes, each touch electrode is provided with a first opening to correspond to the corresponding light-emitting unit, and a first groove is arranged at a gap between the adjacent light-emitting unitscorresponding to the first insulating layer; the touch electrode is arranged in the first groove, the second insulating layer covers the touch electrode in the first groove and is in contact with the first insulating layer at the first opening, and the included angle between the side wall of the first groove and the bottom surface of the first groove is an obtuse angle. According to the display panel and the electronic device, the light emitting efficiency of the panel can be effectively improved.

Distributed Bragg reflectors (DBRs), and VCSELs that use such DBRs, comprised of AlP layers on InP substrates. When grown on an InP substrate, if the critical layer thickness (tcrt) of AlP is greater than λ / 4nAlP, where nAlP is the index of refraction of InP and λ is the wavelength, then the DBR can be grown using alternating layers of InP and AlP, wherein the thickness of the AlP is less than the critical thickness. If the critical layer thickness (tcrt) of AlP is greater than λ / 4nAlP, then the DBR mirror is grown using alternating layers of InP and of an AlP / InP superlattice, wherein the AlP / InP superlattice is comprised of InP and of AlP wherein the thickness of the AlP is less than the critical thickness.

The invention relates to a structural color substrate, an optical element, a manufacturing method thereof and a display device. The structural color substrate comprises a substrate, a plurality of pixel wall structures and a plurality of nano protrusions, the plurality of pixel wall structures are arranged on the substrate in parallel, and a pixel band is defined by two adjacent pixel wall structures; a plurality of nanometer protrusions are independently arranged in each pixel band, and the nanometer protrusions in the pixel bands are arranged in an array mode. The pixel bands are defined through the pixel wall structures, a plurality of nano protrusions are arranged in each pixel band, the plurality of nano protrusions in each pixel band are periodically arranged, and the hue of a certain wavelength can be selectively enhanced by adjusting the interval period of the nano protrusions, so that the hue of a diffraction color is adjusted. As the nanometer protrusions are of a physical structure, the nanometer protrusions are stable and reliable, and the problem that the colloidal particle spacing of colloidal crystal particles in the traditional colloidal ink is difficult to controlis avoided.