485 results about "Diffraction efficiency" 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.

Gradient encapsulation of waveguide outcoupler gratings for control of diffraction efficiency and directionality includes a first grating formed over a substrate, the first grating having a plurality of first structures extending away from the substrate, the first grating corresponding to an outcoupler. The device includes a first encapsulant disposed in one or more gaps formed between adjacent first structures, where a fill ratio of the first encapsulant decreases along the first grating. Also described herein are methods for fabricating the device.

The invention provides a grating assembly and a manufacturing method of the grating assembly. The grating assembly comprises a substrate; the number of the optical cement auxiliary structures is multiple, and the multiple optical cement auxiliary structures are formed on the surface of one side of the substrate at intervals through nanoimprint; the functional layer covers the sides, away from the substrate, of the optical cement auxiliary structures in a shape follow-up mode so that the side faces and the top faces of the optical cement auxiliary structures can be wrapped by the functional layer, and gaps are reserved in the sides, away from the substrate, of the functional layer; the optical adhesive layer is arranged on the side, away from the substrate, of the optical adhesive auxiliary structure, and the projection of the optical adhesive layer on the substrate completely covers the optical adhesive auxiliary structure and the functional layer; the functional layer is a deposition layer, the grating assembly further comprises a plurality of diffraction gratings, and the diffraction gratings are filled in the gaps. The problem that the diffraction efficiency of a grating assembly in the prior art is difficult to improve is solved.

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 method for designing a myopia prevention and control lens based on harmonic diffraction. Relates to the technical field of eye vision optics, in particular to the technical field of a myopia prevention and control lens design method based on harmonic diffraction. According to the method, a harmonic diffractive optical lens chromatic aberration correction method and a harmonic diffractive optical lens diffraction efficiency calculation method when shielding is considered are firstly designed, chromatic aberration is effectively eliminated, the diffraction efficiency is evaluated, and then influences of chromatic aberration correction and shielding error manufacturing are balanced by designing a balance optimization model. The method comprises the following steps: designing a diffractive optical element on the refraction surface of a myopia prevention and control lens to obtain a refractive and diffractive optical lens; modulating the harmonic number # imgabs0 # of the refractive and diffractive optical lens to obtain a harmonic diffractive optical lens; designing a chromatic aberration correction method of the harmonic diffractive optical lens; harmonic diffractive optical lenses are designed that take into account additional refractive power and diffraction efficiency at the time of manufacturing shields.

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 relates to a laser radar on-chip integrated chip based on acousto-optic modulation, an on-chip acousto-optic scanning method and a laser radar system. A plurality of groups of interdigital transducers are arranged on the lithium niobate film, two groups of chirp IDTs respectively work at a low-frequency band and a high-frequency band, and sound waves at the low-frequency band correspondingly generate a relatively large Bragg deflection angle; and the high-frequency-band sound waves correspondingly generate a relatively small Bragg deflection angle. The two groups of IDTs work cooperatively, so that two-dimensional vector scanning of a dual-frequency broadband can be realized in a chip plane; the pair of focusing IDTs can form a focusing sound field in an action area, so that the light beam subjected to two-dimensional deflection is controllably deflected in the Z direction, and the chip is endowed with the three-dimensional scanning capability. The device is high in diffraction efficiency and low in power consumption; unification of large-range search and high-precision scanning is realized; z-axis deflection is realized by integrating a special focusing type interdigital transducer, a three-dimensional scanning function is realized on a monolithic integrated acousto-optic chip, and the structure is extremely compact.

The present invention relates to a transmission grating and a preparation method therefor. The transmission grating comprises: a substrate, which has a first surface; a grating layer, which comprises trapezoidal grating teeth arranged in an array on the first surface, wherein the grating teeth extend in the direction of thickness of the substrate, and a gap is provided between two adjacent grating teeth; and a dielectric layer, which is arranged on a surface of the grating layer and fills the gaps, wherein the dielectric layer has a second surface on the side thereof away from the substrate; there is a difference between the height of the grating teeth and the distance between the second surface and the first surface, the difference being m; and incident light passes through the interior of the grating layer and is incident towards the second surface. By means of the design of a film layer structure and film layer dimensions of the transmission grating, the present invention can acquire transmission gratings having different diffraction efficiencies and polarization degrees, and can accurately control the dimensions of the film layer structure of the transmission grating during machining, thereby facilitating machining.

The invention relates to the technical field of optical equipment, and discloses a diffraction optical waveguide module and an AR device. The diffractive optical waveguide module comprises a diffractive optical waveguide substrate, and a coupling-in grating region, a turning grating region and a coupling-out grating region which are sequentially arranged on the diffractive optical waveguide substrate along a first linear direction; the coupling-in grating region is arranged in the upper half region of the diffractive optical waveguide substrate and is close to the side edge of the upper end part of the turning grating region; wherein the turning grating area is a one-dimensional grating. According to the diffraction optical waveguide module, efficient pupil expansion and diffraction efficiency of the turning grating area are achieved, the lighting effect of the whole diffraction optical waveguide is improved, and therefore the problems of imaging definition, image brightness, rainbow lines and the like in the prior art are solved.

The invention provides a photosensitive glass ceramic with lower visible light absorption loss, which comprises the following components in molar percentage: cation components: 50-65% of Si < 4 + >; 25 to 38% of Na < + >; 2-6% of Zn < 2 + >; 3-9% of Al < 3 + >; 0.001 to 0.1% of Ag < + >; 0.001 to 0.08% of Ce < 4 + >; 0.02 to 0.2 percent of Sb < 3 + >; the negative ion component comprises 88 to 98 percent of O < 2->, 0.001 to 0.09 percent of Sn < 4 + > and 88 to 98 percent of Sn < 4 + >; f-: 2 to 10%; and 0.05 to 2 percent of Br <->. Through reasonable component design, the obtained photosensitive microcrystalline glass is low in visible light absorption loss and can be used for preparing glass elements such as volume Bragg gratings with low optical loss and high diffraction efficiency.

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 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 application relates to a kind of diffractive optical element beam shaping methods based on spatial frequency filtering, obtain incident light beam, based on the homogenization light beam of preset, obtain corresponding geometric analytical phase distribution;Adjust the homogenization light beam to rectangular flat-top light beam, the phase correction processing of obtained geometric analytical phase;Based on spatial frequency filtering method processing the geometric analytical phase after phase correction, get the light field regulation and control distribution requirement after processing, the light field regulation and control distribution requirement after processing has phase and amplitude regulation and control requirement simultaneously;Design diffractive optical element, make it realize the light field regulation and control distribution requirement required, and utilize the diffractive optical element to realize the incident light beam shaping as the rectangular flat-top light beam.The application can realize the light beam homogenization effect of high uniformity, edge sharp and high diffraction efficiency, and obtain wide application prospect in laser welding, photoetching and biomedical and other aspects.

An apparatus is provided. The apparatus includes a light guide configured to guide a first light to propagate in the light guide. The device also includes an optical film coupled with the light guide, the optically anisotropic molecules in the optical film being configured with an in-plane orientation pattern having an in-plane pitch along a predetermined in-plane direction. Azimuth angles of the optically anisotropic molecules are configured to vary non-linearly in a predetermined in-plane direction within in-plane pitches of the in-plane orientation pattern. The optical film is configured to diffract the first light into a plurality of second light at a plurality of predetermined different diffraction efficiencies at a plurality of positions of the optical film.

The utility model relates to the field of laser processing, in particular to a novel silicon-based liquid crystal spatial light modulator, which is characterized by sequentially comprising a complementary metal oxide semiconductor (CMOS) silicon-based back plate (100), a central symmetry aluminum pixel electrode layer (101), a medium reflecting layer (102), a lower orientation layer (103), a liquid crystal molecular layer (104), an upper orientation layer (105), an indium tin oxide (ITO) electrode layer (106), a glass substrate (107) and an anti-reflecting layer (108) from bottom to top. According to the utility model, the reflectivity, the diffraction efficiency and the phase flatness of the silicon-based liquid crystal spatial light modulation device are improved, the electric field is uniformly distributed, the fringe field effect is reduced, the switching speed of phase modulation is effectively improved, the laser processing efficiency and quality are greatly improved, and more laser processing modes are realized. The technical scheme provided by the utility model can be applied to multiple fields of invisible cutting, laser marking, laser welding and the like.

The invention discloses a reflective all-dielectric polarization beam-combining grating suitable for any wave band. The reflective all-dielectric polarization beam-combining grating is composed of a grating etching layer, a phase matching layer, a periodic film system and a grating substrate in sequence from top to bottom. The invention has the characteristics of easy preparation, wide band and high diffraction efficiency, can effectively solve the problems of low PBS anti-laser damage threshold and low synthesis efficiency in the current polarization beam combination technology, and provides solid component support for the realization of the larger array scale and higher power laser synthesis technology in the future.

The invention relates to a heterogeneous diffraction optical waveguide which comprises at least two waveguide units arranged in a stacked mode, and each waveguide unit comprises an optical waveguide sheet and a grating structure arranged on the surface of the optical waveguide sheet. At least one structural parameter of the optical waveguide sheets in the at least two waveguide units is modulated, and the structural parameters of the grating structures are the same, so that diffraction efficiency difference modulation of visible light in the FOV range of 50-70 degrees in the at least two waveguide units is completed. The invention has the advantages of lower cost, shorter processing period, lighter weight and higher red light efficiency.

A diffraction grating includes a plurality of diffraction features and a plurality of grooves. Each groove of the plurality of grooves is adjacent to at least one diffraction feature of the plurality of diffraction features. One or more apodization features include apodization by a varied ratio of the filled region of one or more diffractive gratings to the total period, typically known as the grating fill factor to a gradually alter one or more edges of the plurality if diffraction features of at least one optical element of a waveguide. The one or more apodization features reduce a diffraction efficiency of at least one diffraction order of the diffraction grating.

The invention belongs to the field of spectral measurement and imaging, and particularly discloses a single-photon detection device and a rapid spectrum and imaging system based on the single-photon detection device. According to the invention, the transmission-type optical fiber spectrometer separates polychromatic light of each wave band in space according to the wavelength, couples photons of different wavelengths into the optical fiber array for time delay, delays different wavelengths to different moments, and outputs the time to the single-photon detection device; the single-photon detection device converts photons of different wavelengths which arrive in time in sequence into electric signals, the number of photons at different moments is obtained after amplification and signal processing, and the photons are converted into spectrums. As the transmission-type spectrometer can provide higher diffraction efficiency, higher spectral resolution and higher signal intensity, and the single-photon detection device can provide a faster and more accurate photon discrimination and photon counting method, compared with the prior art, the spectrum can be measured more quickly on the whole, and higher spectral resolution and higher signal intensity are achieved.

This work relates to a geometric-phase metasurface combined with a fluidic circuit for tuning the properties of the metasurface (especially its diffraction efficiency). We consider two aspects of particular interest: A) Dynamic on-demand diffractive optics (operating in transmission), both as optical elements for altering incident light, and as sensors of the refractive index of a fluid; and B) Transparent, reflective displays. Here the display itself is transmissive, but operates in reflection. One application of dynamic on-demand diffractive optics is to replace the lens array often needed in light field displays.

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 is suitable for the field of electrochemical luminescence detection equipment, and provides a dispersion device suitable for electrochemical luminescence detection, which comprises a monochromator body, the monochromator body is composed of a monochromator housing, a reflector assembly, a grating assembly, a collimating mirror assembly, a focus lens assembly, a slit, a flange snap ring and a flange; an M-shaped light path is arranged in the monochromator body, and a slit, a reflector assembly, a collimating mirror M1 in the collimating mirror assembly, a customized blazed grating G1 in the grating assembly and a focusing mirror M2 in the focusing mirror assembly are sequentially arranged in the light propagation direction. The customized blazed grating G1 is designed by adopting specific parameters including the scribed line density, the blazed wavelength, the notch groove depth and the groove width ratio, and primary light energy enhancement and secondary light intensity suppression can be realized; according to the invention, an optical filter is not needed, the diffraction efficiency of a monochromator is improved to 60-86%, the intensity ratio of luminol secondary light to primary light is less than or equal to 1.6%, the detection limit of ruthenium bipyridine is reduced from 100pmol / L to 50pmol / L, and the electrochemical luminescence detection device is suitable for various electrochemical luminescence detection scenes.

The invention discloses a waveguide grating for realizing diffraction efficiency gradual change, a preparation method and equipment. And the grating depth and the duty ratio are monotonically increased along the etching direction, so that the spatial gradient distribution of the diffraction efficiency is obtained. The method comprises the following steps of: firstly, forming periodic photoresist stripes on a substrate by utilizing an interference photoetching technology to obtain an initial grating pattern; and then, the substrate is placed in a plasma etching system, and the depth and duty ratio of the grating are monotonically increased along the etching direction by regulating and controlling the etching time or etching rate of different areas, so that the spatial gradient distribution of diffraction efficiency is realized. The waveguide grating disclosed by the invention effectively compensates attenuation of light in a waveguide transmission process, and the uniformity and imaging quality of AR display application and the like are remarkably improved. The problem of uneven brightness caused by light energy transmission attenuation of the waveguide grating in the prior art can be effectively solved, the manufacturing cost is low, the process expandability is high, and the waveguide grating is suitable for various waveguide optical display scenes such as mixed reality (MR) and virtual reality (VR).

Spectacle lens design data for manufacturing spectacle lenses related to a wearer is provided. The eyeglass lens has a refractive power and at least a partial diffractive additional power, and is provided with a central region having a first diffractive additional power and being adapted to effect emmetropia of the wearer. The spectacle lens is further provided with a peripheral region disposed radially outward of the central region, where the peripheral region has a second diffractive additional power and is adapted to provide a focus in at least one of a front of the wearer's retina or a rear of the wearer's retina. The spectacle lens design data is adjusted such that the spectacle lens further has a first transition region arranged between the central region and the peripheral region, where the first transition region is adapted to adjust a diffraction efficiency from a first diffraction additional power to a second diffraction additional power in a radially outward direction. The spectacle lens has a uniform refractive power extending over at least a central region, a peripheral region, and a first transition region. The uniform refractive power is adjusted to provide focus in front of the retina of the wearer. The central region has a negative diffractive additional power such that a combination of the uniform refractive power and the negative diffractive additional power in the central region is adjusted to achieve emmetropia of the wearer.

The invention relates to a broadband continuous testing device and method for diffraction efficiency of a medium-long wave infrared grating. The device comprises a broadband light source, a medium-long wave infrared monochromator, a collimation system, a polarization selection system, a broadband spectrum beam splitting system, a signal enhancement detection system, a sample clamping and multi-dimensional moving system and an automatic control system. According to the testing method, the absolute diffraction efficiency of the grating is tested through double optical paths, measurement errors caused by fluctuation of a light source can be avoided, the measurement errors are further reduced by deducting environmental noise and improving the signal-to-noise ratio through a signal enhancement detection system, an automatic control system is added, and continuous scanning testing in a specified wave band is achieved. The test speed is improved. By means of the device and the method, automatic and rapid measurement of the diffraction efficiency of the medium-long wave echelette grating under the conditions of at least 2.5-14 micron broadband, different wavelengths, any incident angle and dual polarization states can be achieved.