225 results about "Holographic grating" patented technology

The invention relates to an AR near-to-eye display technology, in particular to a two-dimensional vector body holographic grating waveguide and a manufacturing method thereof, an AR optical module and a manufacturing method, and the method comprises the steps: fixing a holographic plate to be exposed, and building a rectangular coordinate system with a second surface of the holographic plate as an XOY plane; dividing the same exposure light into a first light beam and a second light beam, enabling the first light beam to vertically irradiate the first surface of the holographic plate, and enabling the second light beam to irradiate the second surface of the holographic plate at a # imgabs0 # incident angle so as to form a volume holographic grating with a first grating component; enabling the first light beam to vertically irradiate the first surface of the holographic plate, and enabling the second light beam to irradiate the second surface of the holographic plate at a # imgabs1 # incident angle to form a volume holographic grating with a second grating component; wherein the propagation direction of the orthographic projection of the volume holographic grating vector of the first grating component on the second surface and the propagation direction of the orthographic projection of the volume holographic grating vector of the second grating component on the second surface are symmetric about the X axis.

The invention belongs to the technical field of optical materials, and discloses a holographic polymer dispersed liquid crystal composition, a holographic grating and a preparation method. The composition comprises the following components in parts by mass: 0.5-1.5 parts of a photoinitiator, 2-5 parts of a co-initiator, 15-20 parts of a first monomer, 15-20 parts of a second monomer, 10-15 parts of a third monomer, 10-15 parts of a solvent and 10-20 parts of mixed liquid crystal. Wherein the first monomer is a monofunctional acrylic monomer, the second monomer is a bifunctional acrylic monomer, the third monomer is a polyfunctional acrylic monomer, the mixed liquid crystal comprises 10-25 wt% of a monomer liquid crystal and 75-90 wt% of a nematic liquid crystal, and the monomer liquid crystal contains fluorine as a benzene ring substituent and contains cyano or isothiocyano as an end group. Through cooperation of the monomer liquid crystal and the nematic liquid crystal in the mixed liquid crystal and cooperation of fluorine atoms and cyano / isothiocyano groups in the monomer liquid crystal, the holographic grating prepared from the composition has the characteristics of low haze and high diffraction efficiency, and the grating can be thinner, so that the requirements of light weight and clearness of AR glasses can be met.

According to the device and the method for synchronously locking the phase and the period of the holographic interference fringes, two sets of locking devices are adopted and are respectively arranged at two ends of a holographic interference exposure field in the same direction as the period of the interference fringes, one set is used for compensating the phase of the interference light field to lock the phase of the interference fringes, and the other set is used for locking the period of the interference fringes. And the other one is used for compensating the output laser frequency of the laser to lock the interference fringe period. According to the interference fringe phase and period synchronous locking method, the problem that the contrast ratio of interference fringes is degraded due to phase and period drift of the interference fringes in the exposure process of a large-aperture holographic grating is solved, and particularly an interference fringe period real-time locking module is used; the problem that the fringe contrast is gradually deteriorated in the periodic direction due to periodic change of interference fringes is effectively solved, and a reliable solution is provided for preparation of the meter-scale large-aperture, high-contrast and high-uniformity holographic grating.

The invention discloses a preparation method of a polymer dispersed liquid crystal holographic grating with s polarization high diffraction characteristics, and belongs to the technical field of holographic optics. Raw materials comprise 60-90% of a thiol-ene monomer, 10-40% of liquid crystals, a photoinitiator accounting for 1.25% of the mass of the monomer, and a coinitiator accounting for 1.56% of the mass of the monomer. Light with the wavelength of 532 nm and the light intensity of 5-30 mW / cm < 2 > is used for carrying out double-interference photoetching to generate photochemical reaction so as to generate the polymer grating film, and the light is s polarized light. Under the optimal recording condition, delta n under s polarization can reach 1.93 * 10, and delta n under p polarization can reach 1.21 * 10. In combination with morphology analysis, it is found that refractive index modulation strongly depends on the proportion of a liquid crystal-rich phase to a polymer-rich phase in the grating. It is proved that the size of liquid crystal microdroplets formed by holographic recording is larger due to low recording intensity, and therefore the threshold driving voltage of the HPDLC grating is reduced.

The invention provides an acrylate monomer with a high refractive index and a preparation method and application thereof, the acrylate monomer has a structure as shown in a formula G1, G2 or G3, the refractive index of the acrylate monomer is 1.75 or above, so that a holographic recording medium has higher sensitivity and higher diffraction efficiency, and the holographic recording medium can be applied to the field of holographic recording. The holographic recording medium is used for a holographic grating, so that the holographic grating has high diffraction efficiency and high refractive index modulation degree.

Holographic volume gratings in waveguide cells can be recorded using many different methods and systems in accordance with various embodiments of the invention. One embodiment includes a holographic recording system including at least one laser source configured to emit recording beams and a movable platform configured to move between a first position and a second position, wherein when the movable platform is in the first position, the at least one laser source is configured to emit a first set of one or more recording beams toward a first set of one or more stations and when the movable platform is in the second position, the at least one laser source is configured to emit a second set of one or more recording beams toward a second set of one or more stations.

The invention discloses a photovoltaic ecological system based on a holographic frequency division technology. The photovoltaic ecological system comprises a frame body; the frequency-division concentrating photovoltaic unit comprises a substrate layer which is formed by connecting a heat conducting plate and a dodging plate and is connected with the frame body through a reciprocating motion mechanism, a concentrating layer and a holographic grating layer which are sequentially arranged above the heat conducting plate, and a photoelectric conversion battery arranged on the heat conducting plate; the light adjusting unit is arranged between the two adjacent frequency division concentrating photovoltaic units and comprises two frequency division plates connected through a rotating pair, and the ends, away from each other, of the two frequency division plates are connected with the corresponding frequency division concentrating photovoltaic units through rotating pairs; the reflective optical baffles are arranged on the two sides of the substrate layer, and side wall batteries are further arranged on the sides, close to the light adjusting units, of the reflective optical baffles. According to the invention, through a spectrum frequency division and space light energy distribution mechanism, multi-band efficient utilization of sunlight is realized, the light quality and the light quantity required by plant photosynthesis are guaranteed, and the photovoltaic power generation efficiency is improved.

The invention provides a volume holographic grating exposure parameter determination method and a two-dimensional pupil expansion volume holographic optical waveguide, and the method comprises the steps: carrying out the multiple rotation of a vector of a first light beam, a vector of a second light beam and a holographic photosensitive material when the wavelengths of the first light beam and the second light beam are first recording wavelengths, the rotated vectors of the first light beam and the second light beam and the rotated material position of the holographic photosensitive material are obtained; converting the wavelengths of the first light beam and the second light beam into a second recording wavelength, and rotating the rotated vectors of the first light beam and the second light beam at least once to obtain in-material vectors of the first light beam and the second light beam; determining the in-air vectors of the first light beam and the second light beam according to the in-material vectors of the first light beam and the second light beam; and determining incident angles of the first light beam and the second light beam according to the in-air vectors of the first light beam and the second light beam. According to the method, the manufacturing efficiency of the two-dimensional pupil-expanding body holographic optical waveguide comprising the coupling-in, turning and coupling-out body holographic grating can be improved.

The invention discloses a thiophene monomer, a holographic recording medium, a preparation method and a related device, the structural general formula of the thiophene monomer is shown in the specification, the refractive index of the monomer is larger than 1.8 and smaller than 1.9, the diffraction efficiency can be remarkably improved, the thiophene monomer is applied to preparation of a photopolymer type holographic recording medium, and the photopolymer type holographic recording medium with the sensitivity larger than 100 cm / mJ can be obtained. According to the holographic recording medium, the diffraction efficiency of the recording grating is larger than 95%, the refractive index modulation degree is larger than 0.1, and the shrinkage rate is lower than 1%, and further, the holographic recording medium can be used for preparing a volume holographic grating, a holographic optical element and an optical device.

The invention discloses a (methyl) acrylate monomer, a holographic recording medium, a preparation method and a related device.The structural formula of the (methyl) acrylate monomer is as shown in G1-G19. The preparation method is easy to operate and high in synthesis yield, and further, the holographic recording medium can be applied to holographic recording. According to the photopolymer holographic recording medium, the (methyl) acrylate monomer with the structure is introduced into the photopolymer holographic recording medium, so that the holographic recording medium with high sensitivity, high diffraction efficiency and no yellowing is obtained, and the invention further provides a preparation method of the holographic recording medium. The invention also provides a volume holographic grating, a holographic optical element and an optical device comprising the holographic recording medium.

The invention discloses a thianthrene monomer, a holographic recording medium, a preparation method and a related device, the structural formula of the thianthrene monomer is shown as G1-G6, the refractive index of the thianthrene monomer is larger than 1.7 and smaller than 1.8, the diffraction efficiency can be remarkably improved, and further, the holographic recording medium can be applied to holographic recording. The thianthrene monomer with the structure is introduced into the photopolymer type holographic recording medium, so that the holographic recording medium with high sensitivity, high diffraction efficiency and high refractive index is obtained, and the invention further provides a preparation method of the holographic recording medium. The invention also provides a volume holographic grating, a holographic optical element and an optical device comprising the holographic recording medium.

The invention provides a volume holographic grating waveguide, a manufacturing method thereof and near-to-eye display equipment. The problem that coupled light intensity is not uniform due to transmission light intensity attenuation when light is transmitted in a waveguide substrate can be solved. The volume holographic grating waveguide includes: a waveguide substrate having an in-coupling region and an out-coupling region for transmitting image light from the in-coupling region to the out-coupling region; the coupling-in element is correspondingly arranged in the coupling-in area of the waveguide substrate, and is used for coupling the image light into the waveguide substrate from the coupling-in area; and a volume hologram out-coupling grating, which is correspondingly disposed in the out-coupling area of the waveguide substrate, and is used for coupling the image light out of the waveguide substrate from the out-coupling area. Wherein a thickness of the volume holographic decoupling grating increases along an image light transmission direction at the decoupling region.

The invention discloses a (methyl) acrylate monomer, a holographic recording medium, a preparation method and a related device.The structural formula of the (methyl) acrylate monomer is as shown in G1-G5. The preparation method is easy to operate and high in synthesis yield, and further, the holographic recording medium can be applied to holographic recording. The (methyl) acrylate monomer with the structure is introduced into the photopolymer type holographic recording medium, reverse migration of a short polymer chain can be effectively inhibited, and therefore the holographic recording medium with high sensitivity and high diffraction efficiency is obtained, and the invention further provides a preparation method of the holographic recording medium. The invention also provides a volume holographic grating, a holographic optical element and an optical device comprising the holographic recording medium.

The invention discloses an accelerated simulation method of a gradient period polarization holographic grating and a related device, and the method comprises the steps: carrying out the D (kin) calculation of the direction of predicted incident light after passing through a grating layer, multiplying a calculation result with the amplitude of the corresponding incident light, calculating the diffraction efficiency, and carrying out the acceleration simulation of the gradient period polarization holographic grating. Compared with a traditional simulation method using complete strict coupling wave calculation, the method has the advantages that the process operation of multiple integration, matrix multiplication and matrix inversion is reduced, and the simulation speed can be greatly accelerated.

The invention provides a volume holographic grating preparation method, a volume holographic grating, an optical waveguide and a display device, and the method comprises the steps: obtaining a to-be-exposed holographic material which comprises a thermosetting liquid crystal material; providing a liquid crystal box, and filling the liquid crystal box with the holographic material to be exposed; based on a preset light source, performing exposure treatment on the holographic material to be exposed in the liquid crystal box to obtain a grating to be treated; and applying a preset electric field to the to-be-processed grating and heating the to-be-processed grating to which the preset electric field is applied so as to cure the thermosetting liquid crystal molecules oriented by the preset electric field in the to-be-processed grating, thereby obtaining the volume holographic grating. According to the volume holographic grating, the arrangement state stability of the liquid crystal molecules of the volume holographic grating at a relatively high temperature can be improved, so that the diffraction efficiency of the volume holographic grating is ensured, and the optical performance degradation of the volume holographic grating in a high-temperature state is avoided.

The invention belongs to the technical field of ICP spectral analysis, and particularly relates to an angle-adjustable monochromator type concave holographic grating, a spectrometer and a method. A servo motor in the holographic grating is connected with a lead screw mechanism and can drive a lead screw of the lead screw mechanism to rotate, a polished rod bearing is connected to a connecting block, the connecting block is fixed to the movable end of the lead screw mechanism, a monochromator type concave holographic grating body is connected to a movable base, one end of a polished rod makes contact with the monochromator type concave holographic grating body, and the other end of the polished rod makes contact with the movable base. The other end is matched in the polish rod bearing; according to the invention, two DMDs and a monochromator type concave holographic grating are adopted to realize spatial imaging spectral analysis, the first DMD realizes spatial position selection of an ICP plasma torch, the monochromator type holographic grating realizes high-efficiency and simple-structure rotating grating type light splitting, and the second DMD is selected as an exit slit with adjustable width to carry out fine light splitting on a selected wave band, so that the light splitting efficiency of the ICP plasma torch is improved. Therefore, the spatial imaging spectrum analysis of the ICP plasma torch by the system is realized.

The invention provides a polarization body holographic grating, a preparation method thereof and display equipment, and relates to the technical field of grating preparation. The preparation method comprises the following steps: preparing a first liquid crystal mixture, and filling a first liquid crystal box with the first liquid crystal mixture; ultraviolet curing treatment is carried out on the first liquid crystal box, so that the first photopolymerization liquid crystal is subjected to photopolymerization reaction, and a polymer template is formed; removing the inert nematic liquid crystal in the polymer template to obtain a second liquid crystal box; a second liquid crystal mixture is prepared and added into the second liquid crystal box, and the second liquid crystal mixture at least comprises a second photopolymerization liquid crystal and a second chiral agent; and carrying out ultraviolet curing treatment on the second liquid crystal box, so that the second photopolymerization liquid crystal is subjected to photopolymerization reaction, and the polarizer holographic grating is prepared. The invention aims to realize preparation of the polarization body holographic grating with wide reflection bandwidth and adjustable grating thickness and polarized light rotation direction.

The invention discloses a dendritic (methyl) acrylate monomer, a holographic recording medium, a preparation method and a related device. Wherein the structural formula of the dendritic (methyl) acrylate monomer is shown as G1-G12, the preparation method of the dendritic (methyl) acrylate monomer is simple and easy to operate, and further, the dendritic (methyl) acrylate monomer with the structure is introduced into the photopolymer type holographic recording medium, so that the photopolymer type holographic recording medium is prepared. The invention further provides a preparation method of the holographic recording medium, a volume holographic grating containing the holographic recording medium, a holographic optical element containing the holographic recording medium and an optical device containing the holographic recording medium.

The invention provides a polymerizable monomer with the refractive index larger than 1.7 and a preparation method and application thereof.The polymerizable monomer has the structure shown in the formula G1 or G2 or G3 or G4 or G5 or G6, the refractive index of the polymerizable monomer is 1.7 or above, and therefore a holographic recording medium has various excellent characteristics such as high sensitivity, high diffraction efficiency and high refractive index modulation degree; the holographic recording medium is used for a holographic grating, so that the holographic grating has high diffraction efficiency and high refractive index modulation degree.

The present invention discloses a holographic grating self-calibration method, which relates to the field of optical technology, including collecting interference image data and performing preprocessing, extracting phase data of the interference image data after preprocessing; generating a phase map based on the phase data to perform holographic grating self-calibration, and evaluating and adjusting the result of the holographic grating self-calibration; constructing a visual interface to display the holographic grating self-calibration in real time, implementing secure encryption on the phase data, and storing, collecting and analyzing the generated data. The present invention collects interference image data and performs preprocessing, extracts phase data of the interference image data after preprocessing, and generates a phase map based on the phase data to perform holographic grating self-calibration, which greatly simplifies the calibration process, improves the convenience of operation and the extraction accuracy of phase data, and significantly improves the calibration accuracy and stability of the holographic grating.

Optical systems for performing gaze tracking and imaging an external scene are disclosed. An example optical system may include light sources for emitting visible and non-visible light. The optical system may include a waveguide that is operatively coupled to the light sources. A volume holographic light coupling element may be disposed between the surfaces of the waveguide. The volume holographic light coupling element may include a grating medium and a first volume holographic grating structure within the grating medium. In some examples, the first volume holographic grating structure may be configured to reflect non-visible light of a first wavelength about a first reflective axis offset from a surface normal of the grating medium at a first incidence angle. The optical system may also include an optical filter. Another example optical system may include an imaging device that is configured to receive the light external to the optical system.

The invention discloses a 4, 4 '-bis (omega-alkenyl thioether) diphenyl sulfide monomer and a preparation method, the structural general formula of the 4, 4'-bis (omega-alkenyl thioether) diphenyl sulfide monomer is shown in the specification, n represents the number of methylene and is a positive integer, n = 1-10, the refractive index of a polymer obtained after the monomer and 4 '4-dimercapto diphenyl sulfide are polymerized is larger than 1.65 and smaller than 1.8, diffraction efficiency is remarkably improved, the preparation method is easy to operate, and the preparation method is suitable for industrial production. The invention further provides a photopolymer type holographic recording medium containing the monomer and a preparation method of the photopolymer type holographic recording medium, the sensitivity of the holographic recording medium is larger than 100 cm / mJ, the diffraction efficiency of a recording grating is larger than 95%, the refractive index modulation degree is larger than 0.1, the shrinkage rate is lower than 1%, and the preparation method is simple, controllable and suitable for industrial production. The invention also provides a volume holographic grating containing the holographic recording medium, a holographic optical element and an optical device.

The embodiment of the invention discloses a preparation device and method of a volume holographic grating. The device comprises a coherent light source used for generating coherent light with the coherent length larger than the optical path difference of the grating recording device; the beam expanding and splitting device is used for expanding and splitting the coherent light into object light and reference light with the same polarization direction; the control unit is used for decomposing the volume holographic grating into a plurality of volume holographic sub-gratings related to the grating position; the light modulator unit is used for modulating complex amplitude distribution of an object light wave surface to obtain object light with certain complex amplitude distribution, and the object light with certain complex amplitude distribution and the reference light interfere to form stripes with light intensity distribution corresponding to the volume holographic sub-grating; a light transmission unit for transmitting the object light having a certain complex amplitude distribution and the reference light to a recording medium; and the spatial position adjusting unit is used for bearing the recording medium and adjusting the position of the recording medium according to the signal from the control unit, so that the recording medium records stripes corresponding to the position according to the position to obtain the volume holographic grating.

An electronic device may include a display that generates light for an optical system that redirects the light towards an eye box. The optical system may include a waveguide, a non-diffractive input coupler, a cross coupler, and an output coupler. The cross coupler may expand the light in a first direction. The cross coupler may perform an even number of diffractions on the light and may couple the light back into the waveguide at an angle suitable for total internal reflection. The output coupler may expand the light in a second direction while coupling the light out of the waveguide. The cross coupler may include surface relief gratings or holographic gratings embedded within the waveguide or formed in a separate substrate. The optical system may direct the light towards the eye box without chromatic dispersion and while supporting an expanded field of view and optical bandwidth.

The invention discloses an optical fiber type interference exposure system and an interference exposure adjustment method, and relates to the technical field of holographic gratings, and the system comprises a light guide assembly which comprises a first optical fiber and a second optical fiber; the grating substrate is provided with a plurality of exposure positions, and the first coherent light and the second coherent light led out by the light guide assembly form an interference exposure field on the grating substrate; the compensation device is provided with a plurality of compensation areas, each compensation area is provided with a compensation deflection angle corresponding to one exposure position, and the compensation device is arranged on a propagation path of at least one beam of light in the first coherent light and the second coherent light. Therefore, the interference solid angles of the incident first coherent light and the second coherent light at the corresponding exposure positions are adjusted through the compensation area on the compensation device, so that the grating obtained by interference exposure has the same grating angle at different exposure positions of the grating substrate, and the consistency and uniformity of the grating angle are ensured; and a good imaging effect of the grating is achieved.

The invention discloses a dithiocarbamate monomer, a holographic recording medium, a preparation method and a related device, the structural general formula of the monomer is as shown in G1 and G2, R1 represents any one of hydrogen, halogen and C1-C4 alkyl, R3 represents any one of hydrogen, halogen and C1-C4 alkyl, A1 represents C1-C4 alkyl, A2 represents hydrogen or methyl, n is a positive integer, and n = 1-10. The dithiocarbamate monomer provided by the invention has high refractive index, and the holographic recording medium with high sensitivity, high diffraction efficiency and high refractive index modulation degree can be obtained by applying the dithiocarbamate monomer to preparation of the photopolymer holographic recording medium; holographic recording media can be used to prepare volume holographic gratings, holographic optical elements, and optical devices.

The invention provides a photopolymer system, a grating device containing a chirp structure and a preparation method of the grating device. Visible light and ultraviolet light dual initiators and azobenzene polymerizable acrylate monomers are introduced into the photopolymer system; by utilizing the characteristics that an acrylate group can be used as a writing monomer to participate in a copolymerization process and an azobenzene group can be subjected to continuous photoisomerization during holographic exposure, a visible light photoinitiator and an ultraviolet light initiator driving system are reacted and cross-linked in sequence; a chirp structure is induced to be generated in the formed volume holographic grating while the photopolymer system records interference fringes, so that grating period change caused by material shrinkage is effectively compensated, the angle response bandwidth of the grating is remarkably widened, the requirement for refractive index modulation of the photopolymer system is reduced, and the optical grating has a wide application prospect. According to the invention, the selection range of the photopolymer system is widened, the overall aging resistance of the material system is improved, and the service life of the grating device is prolonged.

The invention discloses an acrylate monomer and a preparation method thereof, a photopolymer composition and a volume holographic grating and a preparation method thereof, the acrylate monomer provided by the invention is simple in structure and rich in expandable structure, so that the synthesis steps are simple and convenient, the cost is reduced, a relatively high refractive index of the monomer is realized on the basis of introduction of more sulfur atoms into the monomer, and the volume holographic grating has a good application prospect. In the subsequent photopolymerization process, the difference between the refractive index of the generated polymer and the refractive index of the common matrix is larger, so that the preparation of the holographic grating with high-refractive-index modulation degree can be realized.

The invention discloses a partition display system and method based on a polarization body holographic grating, and belongs to the technical field of display, and the system comprises a light source layer, a collimation optical layer, an electric control light diffusion layer, a polarization body holographic grating array layer and a liquid crystal display layer which are sequentially arranged from bottom to top; the light source layer can independently generate left-hand circularly polarized light and right-hand circularly polarized light; the collimating optical layer can convert light emitted by the light source layer into collimated light beams; the electric control light scattering layer has a transparent mode and a scattering mode which can be switched; the polarization body holographic grating array layer is formed by alternately arranging left-hand circular polarization gratings and right-hand circular polarization gratings; when the electric control light scattering layer is in a transparent mode, the liquid crystal display layer only performs rendering display on an area through which refracted light of the polarization body holographic grating array layer passes; and when the electric control light scattering layer is in a scattering mode, the liquid crystal display layer renders and displays all areas through which light passes. The invention has the advantages of high luminous efficiency utilization rate, low visual area crosstalk, ultra-thinness and the like.

The invention discloses a small-size single-layer full-color AR optical waveguide based on LCoS, the AR optical waveguide structure comprises an LCoS optical engine, a parallel plate, a coupling-in gradual change period polarization body holographic lens and a two-dimensional coupling-out polarization body holographic grating, and the LCoS is connected with the parallel plate in an optical gluing mode; the gradient period polarization holographic lens is coupled to achieve the effect of light collimation and light deflection coupling, and the wavelength bandwidth is expanded to the visible light range through variable period processing. The two-dimensional coupling-out polarization body holographic grating is used for expanding light rays to two directions, and the pupil expanding effect is achieved. According to the structure, the problem that an LCoS light machine depends on a projection lens, and the size is too large is solved, and the single-layer full-color AR optical waveguide under the small size is achieved.