181 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.

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 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.

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 relates to the technical field of display, in particular to a volume holographic grating raw material system, a volume holographic grating and a preparation method of the volume holographic grating. The volume holographic grating raw material system comprises a photopolymerizable monomer, a liquid crystal, an organic additive and a photoinitiator, the structural formula of the organic additive is A-B, A is a photopolymerizable monomer affinity group, and B is a liquid crystal affinity group. On the basis of a raw material system composed of a photopolymerizable monomer, liquid crystal and a photoinitiator, a novel organic additive is introduced, and the organic additive is beneficial to good phase separation of a PDLC system and increase of the refractive index difference between a bright area and a dark area, so that the refractive index modulation degree of the volume holographic grating is improved, and the display application in the AR / VR field is met.

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.

The invention relates to the technical field of measurement, in particular to an automatic calibration device and method for a spectrograph. Comprising a light source, an optical isolator, an optical fiber coupler, a standard reference light source, an adjustable optical fiber attenuator, a first optical fiber collimator, a holographic frequency selection module, an electric reflector, a volume holographic grating, a second optical fiber collimator, a beam splitter, an optical interface unit, a spectrometer to be tested, a photoelectric detector, an electric reflector driver, an arc second level angle encoder, a control module and a communication module. A computer and an image display unit. The volume holographic grating is used for selecting a specific wavelength to measure the corresponding relation between the spectrograph pixel and the wavelength, monochromatic light can be continuously selected, and the theoretical resolution is consistent with the spectral resolution of the light source; automatic calibration of the spectrometer is realized by using an automatic calibration method, pixel-wavelength calibration data can be automatically generated and stored in a preset format, automatic calibration and data processing of spectral measurement software are facilitated, and pixel-level wavelength-pixel position registration is realized.

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 a cold atom regulation and control chip device based on a composite waveguide holographic grating, and the structure is mainly composed of a silicon nitride waveguide disposed on a silicon dioxide substrate, and the silicon nitride waveguide comprises a group of x-direction waveguides and two groups of y-direction waveguides. A composite waveguide holographic grating G1 and a composite waveguide holographic grating G2 are respectively etched in the crossed area of the waveguides; the port of the y-direction waveguide is diffracted by the composite waveguide holographic grating G1 and the composite waveguide holographic grating G2 to generate two beams of vortex light, and the two beams of vortex light are intersected above the chip to form an optical dipole trap for trapping cold atoms; the x-direction waveguide is diffracted by the composite waveguide holographic grating G1 through the port Pin to generate Gaussian light, and the Gaussian light is focused and aligned with the center of the optical dipole trap. According to the invention, the functions of atom capture, atom internal state excitation and fluorescence detection can be realized on the chip, and the problem of contradictory integration compatibility of a device for regulating and controlling a plurality of cold atoms in the existing photon-atom chip is solved.

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.