136 results about "Holographic grating" patented technology

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.

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.

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 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 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 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.

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 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 a multi-focal near-to-eye display holographic optical element and a preparation method and device thereof. The element adopts a composite structure of a substrate, a multi-focal correction layer and a holographic recording layer, a holographic grating accurately matched with each optical partition of the correction layer is formed in the recording layer through a partition exposure technology, and multi-depth virtual image display and user refraction correction functions can be realized at the same time. The preparation device comprises a coherent light source, a beam splitter, a diffusion plate, a focal plane displacement system, a mask component and a master controller, and partition exposure is realized through cooperative control. The problem that traditional near-to-eye display cannot meet multi-focus display and refraction correction at the same time is solved, a user can clearly perceive fused multi-depth virtual information and a real environment without additionally wearing glasses, the visual comfort and experience are remarkably improved, and the method is suitable for AR / VR and other head-mounted display devices.

A volume holographic grating, a method for formulating a grating vector distribution formulation thereof, and a method and apparatus for manufacturing the volume holographic grating. The grating vector distribution is estimated by sampling a position of an eye movement range effective region of a plurality of sub-fields of view and a grating vector, matching with Bragg diffraction conditions, of a ray thereof, without considering the diffraction of ineffective rays that ultimately enter beyond the eye movement range, such that most of the effective rays with different incident angles have higher diffraction efficiency on the volume holographic grating, which ensures the overall brightness uniformity of the output beams and extend the field of view.

The invention provides a polymer composition, a polymer film material, a holographic grating, a preparation method of the holographic grating, an optical film material and display equipment. The polymer composition comprises a first polymerizable monomer, a second polymerizable monomer and a film-forming resin. The first polymerizable monomer is a non-liquid crystal monomer; the second polymerizable monomer is a liquid crystal monomer, the second polymerizable monomer comprises an active group, and the second polymerizable monomer can be subjected to a copolymerization reaction with the first polymerizable monomer through the active group under illumination. The refractive index modulation degree of the optical film material can be improved by using the polymer composition.

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 relates to the technical field of holographic gratings, in particular to a holographic grating with a high refractive index modulation degree and a preparation method thereof, and the preparation method comprises the steps: coating a grating substrate with a precursor material to form a coating, and preparing a holographic dry plate with a holographic material layer; performing interference exposure on the holographic plate to obtain a semi-finished grating; bleaching the semi-finished product grating, and soaking the semi-finished product grating in an extraction liquid to obtain a grating precursor with a groove; and filling the groove with a fluorine-containing polymer dopant to obtain the holographic grating. The part, corresponding to the exposure bright area, of the grating precursor with the grooves is a polymer with a high refractive index, the inert body in the exposure dark area is removed, air is left, the grooves are formed in the surface of the grating, the appearance of the grooves fluctuates, the grooves are filled with low-refractive-index substances, and finally the high-refractive-index substances in the bright area are formed. The dark area is of a grating structure made of a low-refractive-index material; by adopting a two-step processing method, the holographic grating without light leakage in the reverse direction can be manufactured.

The invention discloses an optical monomer, a holographic recording medium, a preparation method and a related device, the structural general formula of the optical monomer is as shown in G1-G6, the monomer is high in refractive index, the preparation method is simple, and further, the optical 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.

Provided in the present application are an exposure parameter determination method and apparatus for a volume holographic grating, and a two-dimensional exit pupil expansion volume holographic optical waveguide. The method comprises: when the wavelengths of a first light beam and a second light beam are a first recording wavelength, rotating a vector of the first light beam, a vector of the second light beam, and a holographic photosensitive material multiple times, so as to obtain rotated vectors of the first light beam and the second light beam, and a rotated material position of the holographic photosensitive material; shifting the wavelengths of the first light beam and the second light beam to a second recording wavelength, and rotating at least once the rotated vectors of the first light beam and the second light beam, so as to obtain in-material vectors of the first light beam and the second light beam; on the basis of the in-material vectors of the first light beam and the second light beam, determining in-air vectors of the first light beam and the second light beam; and on the basis of the in-air vectors of the first light beam and the second light beam, determining the incident angles of the first light beam and the second light beam. The method can improve the manufacturing efficiency of a two-dimensional exit pupil expansion volume holographic optical waveguide including coupling-in, turning and coupling-out volume holographic gratings.

The present disclosure relates to a holographic grating which includes a holographic photopolymer, and to an augmented reality / virtual reality apparatus including the same. The holographic grating may include at least one nanoparticle, a light portion, a dark portion, and a holographic photopolymer. The holographic photopolymer may also include a polymer matrix, a writing monomer, and a dye system. The holographic photopolymer may be dispersed throughout the light portion and the dark portion of the holographic grating. In some forms, the light portion may include a first concentration of the nanoparticles and / or the dark portion may include a second concentration of the nanoparticles. The first concentration of the nanoparticles may be greater than the second concentration of the nanoparticles.

The invention discloses a simulation method and device of an AR optical system, a medium and electronic equipment, and the method comprises the steps: obtaining an initial source file, converting the initial source file into a target file based on a Kogelnik coupling wave theory and a preset volume holographic grating structure requirement, and importing the target file into ZEMAX; acquiring a corresponding luminous source according to preset parameters of the display; obtaining an initial collimation component, converting the initial collimation component into a target collimation component, and importing the target collimation component into the ZEMAX; in a non-sequence mode of ZEMAX, calling a target file, generating a volume holographic grating, and obtaining a holographic waveguide assembly; and connecting the light emitting source, the target collimation assembly, the holographic waveguide assembly and a preset detector to obtain the target AR optical system. Compared with the prior art, simulation of the holographic waveguide assembly and simulation of the integrity of the AR optical system can be achieved, the simulation efficiency is improved, the systematicness, integrity and quality of simulation are improved, and then the optical performance of the optical system in AR equipment is improved.

The present invention relates to a computed tomography spectrometer based on a metasurface diffraction element. The computed tomography spectrometer includes an optical system structure, a focal plane detector, and a data acquisition and processing system; the optical system structure includes a converging lens group, a field stop, a collimating lens group, a metasurface holographic grating, and an imaging lens group. The present invention combines a metasurface with a computed tomography spectrometer, which can avoid the manufacturing difficulties of the computed tomography spectrometer, miniaturize the computed tomography spectrometer, and produce a better diffraction effect, so that the focal plane array target surface and the overall size of the spectrometer are both in the millimeter range, and can realize an imaging spectrometer with a mobile phone terminal or even smaller structure.

This application discloses a holographic material and its preparation method, a holographic optical element, a holographic device, and a method for preparing a volume holographic grating. The method for preparing the holographic material includes: providing a blocked polyisocyanate, a first compound, a polymerizable monomer, a photoinitiator, and other additives; and mixing the blocked polyisocyanate, the first compound, the polymerizable monomer, the photoinitiator, and the other additives uniformly under light-protected conditions to obtain the holographic material. This method allows for the pre-mixing and long-term storage of second-order holographic materials, control of first-order reactions, and improvement of the overall volume holographic grating preparation process.

This invention discloses an accelerated simulation method and related apparatus for a graded periodic polarizer holographic grating. The invention performs D(k) calculations on the predicted direction of the incident light after passing through the grating layer. in After calculation, the result is multiplied by the corresponding incident light amplitude to calculate the diffraction efficiency. Compared with the traditional simulation method that uses complete and rigorous coupled wave calculation, this method reduces the number of integrations, matrix multiplications and matrix inversions, which can greatly accelerate the simulation speed.

The present application relates to the technical field of measurement, in particular to a kind of spectrometer automatic calibration device and method, comprising: light source, optical isolator, fiber coupler, standard reference light source, adjustable fiber attenuator, first fiber collimator, holographic frequency selection module, electric reflector, volume holographic grating, second fiber collimator, beam splitter, optical interface unit, to be measured spectrometer, photoelectric detector, electric reflector driver, angle-second level angle encoder, control module, communication module, computer and image display unit.The present application utilizes volume holographic grating to select the corresponding relationship between the pixel of spectrometer and wavelength, can continuously select monochromatic light, and the theoretical resolution is consistent with the spectral resolution of light source;Using automatic calibration method, the automatic calibration of spectrometer is realized, pixel-wavelength calibration data can be automatically generated and stored in preset format, which is convenient for automatic calibration and data processing of spectral measurement software, and realizes wavelength-pixel position registration at pixel level.

An LCoS-based compact single-layer full-color AR optical waveguide, comprising an LCoS optical engine (1), a parallel plate (2), a coupling-in graded-period polarization volume lens (3) and a two-dimensional coupling-out polarization volume grating (4), wherein the LCoS optical engine (1) is connected to the parallel plate (2) by means of optical bonding; the coupling-in graded-period polarization volume lens (3) achieves the effects of light collimation and light defection and coupling, and undergoes graded-period processing to extend the wavelength bandwidth thereof to a visible light range; and the two-dimensional coupling-out polarization volume grating (4) is used for expanding light in two directions, thereby achieving a pupil expansion effect. The full-color AR optical waveguide solves the problem of an LCoS optical engine being excessively large due to the reliance on a projection lens, thereby enabling the implementation of a compact single-layer full-color AR optical waveguide.

The invention discloses a non-contact measuring head device and a measuring method for a nanometer coordinate measuring machine, and the measuring head device comprises a laser holographic measuring module, an optical microscopic imaging module and a signal processing module. The laser holographic measurement module comprises a semiconductor laser, a straight stripe grating close to the semiconductor laser, a holographic grating far away from the semiconductor laser, a first photoelectric detector, a second photoelectric detector, a first lens, a second lens, a first spectroscope and a microscope objective, wherein the first photoelectric detector and the second photoelectric detector are located on the left side and the right side of the semiconductor laser respectively. The signal processing module calculates out-of-focus error signals according to the electric signals obtained by the laser holography measurement module, calculates out-of-focus amount of each measurement point on the surface of the sample according to the linear relation between the out-of-focus amount of the surface of the measured sample leaving the focal plane of the microscope objective and the out-of-focus error signals, and calculates out-of-focus amount of each measurement point on the surface of the sample according to coordinate values of the nanometer coordinate measurement machine. And obtaining the coordinate value of each measuring point on the surface of the sample. According to the invention, the aiming resolution can be improved, and high-precision and high-resolution three-dimensional measurement is realized.