125results about How to "High diffraction efficiency" patented technology

Architectures are provided for selectively incoupling one or more streams of light from a multiplexed light stream into a waveguide. The multiplexed light stream can have light with different characteristics (e.g., different wavelengths and/or different polarizations). The waveguide can comprise in-coupling elements that can selectively couple one or more streams of light from the multiplexed light stream into the waveguide while transmitting one or more other streams of light from the multiplexed light stream.

A polarization grating comprising a polarization sensitive photo-alignment layer (2) and a liquid crystal composition (3) arranged on said photo-alignment layer is provided. An alignment pattern, corresponding to the polarization pattern of a hologram, is recorded in the photo-alignment layer, and the liquid crystal composition is aligned on the photo-alignment layer. As the origin for the alignment of the liquid crystal composition is a polarization hologram recorded in a photo-alignment layer, an essentially defect-free pattern can be obtained with this approach.

In various embodiments described herein, a device comprising a light collector optically coupled to a photocell is described. The device further comprises a light turning film or layer comprising volume or surface diffractive features or holograms. Light incident on the light collector is turned by volume or surface diffractive features or holograms that are reflective or transmissive and guided through the light collector by multiple total internal reflections. The guided light is directed towards a photocell. In various embodiments, the light collector is thin (e.g., less than 1 millimeter) and comprises, for example, a thin film. The light collector may be formed of a flexible material.

A method of producing a hologram element is disclosed that is able to prevent spread of a polymerization reaction and light leakage during exposure with interference light, and improve productivity in mass production. The hologram element is for transmitting, reflecting, diffracting, or scattering incident light, and includes a pair of substrates, an isolation member between the substrates that forms an isolated region, and a photo-sensitive recording material sealed in the isolated region. The hologram element includes a periodic structure formed by exposing the recording material to interference light. The interference light is generated by two or more light beams, or by using a master hologram. The recording material is formed from a composite material including a polymerized polymer or a polymerized liquid crystal. The periodic structure is formed by exposing the recording material to the interference light to induce the polymerization reaction and phase separation in the composite material.

The invention discloses mask-alignment aligning system and its grade combining system. The aligning system includes light source module, illumination module, imaging module, and detecting module. The grade combining system makes positive negative grade frequency spectrum facula of the alignment mark diffraction spectrum process corresponding overlap coherent, uses polychromatic light separating system to separate multiple wavelength light signal, measures light intensity or phase change at the corresponding position of the multiple wavelength multistage secondary diffracted facula to gain alignment mark position information. The invention has high alignment precision and stability.

The invention discloses a holographic waveguide display device and belongs to the technical field of wearable display. The holographic waveguide display device comprises a micro displayer, a collimating lens, a diaphragm, a waveguide, an inlet coupling diffraction optical element and an outlet coupling diffraction optical element. The inlet coupling diffraction optical element comprises a reflection body holographic grating and a sub-wavelength one-dimensional metal nanometer grating. One side of the reflection body holographic grating is closely connected to the waveguide, and the sub-wavelength one-dimensional metal nanometer grating is arranged on the surface of the other side of the reflection body holographic grating. Photons penetrating through the reflection body holographic grating can be coupled into a surface plasma mode through the sub-wavelength one-dimensional metal nanometer grating, and thus the photons can enter the reflection body holographic grating again to be diffracted and enter the waveguide. Compared with the prior art, by means of the holographic waveguide display device, the diffraction efficiency of TM light can be improved on the premise of ensuring the high diffraction efficiency of the TE light, so that the total light energy utilization rate of the holographic waveguide display device is increased, and meanwhile stray light in transmission is effectively suppressed.

A diffractive optical element of the blazed-binary grating type is disclosed, with which a high diffraction efficiency can be achieved over substantially the entire used wavelength region. The diffractive optical element has a periodic structure taking a grating unit including a plurality of grating portions with different grating width and grating interval as one period. The diffraction element further includes a plurality of first grating portions made of a first material and a plurality of second grating portions made of a second material having a different refractive index than the first material that are arranged between the first grating portion.

A substrate is subjected to holographic exposure to a sinusoidal or half-sinusoidal resist pattern corresponding to grating groove thereon. Thereafter, the substrate and the resist pattern are subjected to a first etching step at which they are irradiated with an ion beam obliquely at an angle that is identical to the blaze angle in the presence of CF₄ as an etching gas, whereby they are cut until the height of the resist is about ⅓ of the initial value. Thereafter, the substrate is subjected to a second etching step at which the substrate is irradiated with an ion beam in the direction corresponding to the bisector of the vertex in the presence of a mixture of CF₄ and O₂ as an etching gas, whereby the substrate is cut until the resist disappears completely to an extent such that some overetching occurs.

The Holographic Beam Combiner, (HBC), is used to combine the output from many lasers into a single-aperture, diffraction-limited beam. The HBC is based on the storage of multiple holographic gratings in the same spatial location. By using a photopolymer material such as quinone-doped polymethyl methacrylate (PMMA) that uses a novel principle of “polymer with diffusion amplification” (PDA), it is possible to combine a large number (N) of diode lasers, with an output intensity and brightness 0.9 N times as much as those of the combined outputs of individual N lasers. The HBC will be a small, inexpensive to manufacture, and lightweight optical element. The basic idea of the HBC is to construct multiple holograms onto a recording material, with each hologram using a reference beam incident at a different angle, but keeping the object beam at a fixed position. When illuminated by a single read beam at an angle matching one of the reference beams, a diffracted beam is produced in the fixed direction of the object beam. When multiple read beams, matching the multiple reference beams are used simultaneously, all the beams can be made to diffract in the same direction, under certain conditions that depend on the degree of mutual coherence between the input beams.

The backlight for a flat display device including a light source, a light guide plate and a surface hologram is provided. The light guide plate is installed at one side of the light source, and light from the light source travels in the light guide plate while being totally reflected. The surface hologram is formed on at least one surface of the light guide plate. The surface hologram has a pattern of a predetermined grating interval and a predetermined grating depth in order to diffract light at a predetermined angle toward the light guide plate.

The invention discloses a holographic optical waveguide, and belongs to the technical field of augmented reality and virtual reality. The holographic optical waveguide comprises a planar optical waveguide, and an optical coupling in end and an optical coupling out end which are respectively arranged at the two ends of the planar optical waveguide. The optical coupling in end reflects received light rays so that the reflected light rays are enabled to meet the total reflection conditions to be transmitted to the optical coupling out end through multiple times of total reflection between the two reflecting surfaces of the planar optical waveguide. The received light rays are diffractively emergent out of the optical coupling out end. The optical coupling out end is a holographic grating. The holographic grating is a polarization holographic liquid crystal grating comprising a transparent substrate, a light orientation layer and a liquid crystal layer which are arranged in turn, wherein polarization holographic patterns having periodic structures are recorded on the light orientation layer. The invention also discloses a holographic optical waveguide display device. The polarization holographic liquid crystal grating is used as the optical coupling out end of the holographic optical waveguide so that 100% of diffraction efficiency can be achieved theoretically, and zero order waves can be suppressed and conjugate images can be eliminated.

The invention provides a method for manufacturing triangular groove echelon gratings with 90-degree vertex angles. Each triangular groove echelon grating is composed of a silicon grating structure (1), photoresist (3) and a metal film (4). A manufactured grating groove is a triangle with the vertex angle being 90 degrees, so that the diffraction efficiency higher than that of an echelon grating with the vertex angle being not 90 degrees can be achieved. Each grating structure is produced in an obliquely-cut monocrystalline wafer, the shining angles of the gratings are determined by an obliquely-cut angle for cutting each silicon wafer, and gratings with any blazing angles can be manufactured; according to the 90-degree vertex angles, grooves of silicon gratings with the vertex angles being not 90 degrees are filled with photoresist, then photoetching is conducted again, and the original silicon gratings with the vertex angles being not 90 degrees are converted into the triangular groove gratings with the vertex angles being 90 degrees. According to the manufactured grating structure, the shining face of each grating is a smooth monocrystal silicon <111> grate plane, scattering can be effectively lowered, and the diffraction efficiency of each grating is improved. The purpose that all the gratings have high diffraction efficiency on a broadband is achieved according to the fact that using wave bands can choose to be coated with various different reflecting film layers on the surfaces of the gratings.

An organic-inorganic composite material contains a cured material of an organic-inorganic composition containing a resin component, fine particles of a transparent conductive substance, and a polymerization initiator. Refractive properties of the Abbe number νd and anomalous dispersion θg, F of the organic-inorganic composite material are within a range surrounded by (νd, θg, F)=(16, 0.50), (16, 0.40), (23, 0.50), (23, 0.47). The content of the fine particles of the transparent conductive substance in the organic-inorganic composite material is from 7.7% to 20.0% by volume. The resin component contains a compound represented by the following formula:

where R₁ and R₂ represent a hydrogen atom or a moiety containing a polymerizable functional group such as an acrylic group, a methacrylic group, an allyl group, a vinyl group, or an epoxy group or one or both of R₁ and R₂ represent the moiety containing the polymerizable functional group.

The invention discloses a super-surface color vector complex amplitude holographic element, which comprises a bimetallic nanorod unit structure with adjustable in-plane rotation angles and in-plane displacement, wherein an aluminum-silicon dioxide-aluminum super-structure grating structure generates a polarization-selective type diffraction efficiency enhancement effect in a visible light range; asum of in-plane displacement of two metal nanorods in the unit structure and diffraction phase information are in a linear modulation relationship, a difference between the rotation angles of the twometal nanorods and a diffraction light amplitude are in a sinusoidal modulation relationship, and a sum of the rotation angles of the two metal nanorods and a diffraction light polarization directionare in a linear modulation relationship; and a color holographic method is implemented on diffraction level by utilizing the phase displacement based on inherent dispersion of the super-structure grating. The super-surface color vector complex amplitude holographic element disclosed by the invention has the advantages of low requirements for preparation control precision, simple structure, high degree of control freedom and the like, and has powerful functions of simultaneously controlling four parameters of light wave phase, polarization, amplitude and frequency.

The invention discloses an electronic-control high-efficiency holographic grating made of polymer dispersed liquid crystal materials doped with nano metal and a preparation method of the holographic grating. The preparation method comprises the following steps, uniformly mixing and heating polymer dispersed liquid crystal materials containing nano metal particle materials by an ultrasonic emulsification instrument under the light shading condition, standing for 24-48h in a dark room, then injecting the polymer dispersed liquid crystal materials into a liquid crystal box, and then arranging the packaged liquid crystal box at a holographic light field of a helium-cadmium laser for exposure to finally obtain the electronically-controlled high-efficiency holographic grating made of polymer dispersed liquid crystal materials doped with nano metal. In the steps, the polymer dispersed liquid crystal materials comprise the following components by weight: 0.1-0.2% of photoinitiator, 0.3-0.5% of coordinated initiator, 9-11% of cross linking agent, 9-10% of surface active agent, 0.1-0.2% of nano metal particles, 40-50% of polymers and 30-40% of nematic liquid crystal. According to the electronic-control high-efficiency holographic grating made of polymer dispersed liquid crystal materials doped with nano metal, the diffraction efficiency reaches up to 85%-95%, the response speed is less than 1ms, and the electro-optic properties are improved remarkably.

A composition comprising a polymer represented by the following formula (i), wherein the composition exhibits photorefractive ability:

wherein R is selected from the group consisting of a linear alkyl group with up to 10 carbons, a branched alkyl group with up to 10 carbons, and an aromatic group with up to 10 carbons; n is an integer of 10 to 10,000; Z is a group which contains at least a tri-aromatic amine moiety shown in the structure (ii):

wherein Ra₁-Ra₁₄ are independently selected from the group consisting of a hydrogen atom, a linear alkyl group with up to 10 carbons, a branched alkyl group with up to 10 carbons, and an aromatic group with up to 10 carbons.

A multi-layered diffraction optical element, comprises a transparent substrate, a first layer having a diffraction grating shape at least on one face and comprised of a relatively high refractive index and low dispersion material, and a second layer having a diffraction grating shape at least on one face and comprised of a relatively low refractive index and high dispersion material, wherein the first and second layers are laminated on the transparent substrate so that the respective diffraction grating shapes are mutually opposed to each other with no space therebetween, and, the first layer is comprised of a first organic resin including a first inorganic fine particle, and the second layer is comprised of a second organic resin including a second inorganic fine particle different from the first inorganic fine particle.

The invention relates to a preparation method of an X-ray zone plate. An atomic layer deposition (ALD) method is used to depose alumina/hafnium oxide or alumina/iridium films of different density andthickness alternatively at the surface of a metal wire whose diameter is of a micron order, namely, a first deposed alumina film layer and a second deposed hafnium oxide film or iridium film layer arearranged alternatively and cyclically to form a series of concentric circular rings. The film plated metal wire is cut and polished by focusing ion beams after film plating, and the zone plate of therequired thickness and precision is obtained. The method is suitable for preparing different types of zone plates.

The invention discloses a high-power laser diffraction type spatial filter. The left side of the high-power laser diffraction type spatial filter is provided with an interstage isolation filter of which the central axis is a vertical line BC, the middle of the high-power laser diffraction type spatial filter is provided with a group of gain medium of which the central axis is a transverse line CD, the right side of the high-power laser diffraction type spatial filter is provided with a multi-pass cavity filter of which the central axis is a vertical line DE, the central axis of the entire device forms a BCDEF broken line, one optical grating which enables light beams to be deflected at 90 degrees is respectively arranged at a point B, a point C, a point D and a point E, the optical gratings are separate type volume Bragg optical gratings or double-piece integrated type optical gratings, and one reflecting mirror is arranged at a point F. The invention uses an optical grating double-pass spatial filter component which does not have a lens and a pinhole and has compact appearance to replace a pinhole filter in a multi-pass amplifier, can realize the wider width of a diffraction frequency band and can meet the requirement of short-pulse and ultrashort-pulse spatial filtering; the borne laser power is higher, and the requirement of high-power laser spatial filtering can be met, thereby eliminating the probability that laser burns out the filter component because of no lens and no pinhole in the device.

The invention discloses a high-efficiency oblique double-layer optical grating which is used for vertical incidence of TE polarization light with wave length of 1064nm. First layer materials of the optical grating are quartz, second layer materials are Ta2O5, a base is made of quartz, and the two layers of the optical grating have the same depth. The optical grating cycle of the optical grating is 950-954nm, the ridge width is 441-445nm, the oblique angle is 68-69 degrees, the optical grating total depth is 2046-2050nm, and when vertical incidence of the TE polarization light happens, the transmission light -1 level diffraction efficiency can be higher than 91%. The TE polarization vertical incidence quartz -1-level high-efficiency oblique double-layer optical grating is formed by the fact that an electron beam direct-writing device is combined with a microelectronic deep-etching technology, material taking is convenient, manufacturing cost is low, large-batch production can be achieved, and important practical prospect is achieved.

The invention relates to a light guide plate with embedded diffraction elements, which comprises three superimposed slave light guide plates. The slave light guide plates are arranged independently and respectively comprise a light inlet surface, a bottom surface and a light outlet surface, wedge-shaped bevel are formed among the light inlet surfaces and the bottom surfaces, incident light can be fully transmitted in the slave light guide plates due to the wedge-shaped bevels, and the light outlet surfaces are provided with diffraction regions at intervals so that emergent light fields of the three slave light guide plates cannot be overlapped. Novel diffraction elements are embedded in the diffraction regions of the slave light guide plates and adopt shining surface-coated gratings, and the inclined surfaces of the shining gratings are coated with dielectric films. The three slave light guide plates can be respectively used for transmitting R, G and B beams, the diffracted beams can be transmitted to corresponding pixel positions of a liquid crystal panel, and no color filter is needed. When the collimated light beam is coupled into the light guide plate disclosed by the invention, the brightness of the whole panel is uniform, and the rate of light utilization is high.

The invention provides a broad-band high-diffraction-efficiency asymmetric morphology reflection grating which is characterized in that a grating structure is formed by a top grating ridge structure, an intermediate high-reflectivity film layer and a bottom substrate, wherein the top grating ridge structure has asymmetric morphology, and base angles alpha and beta of the quadrangle in the asymmetric morphology are not equal. According to the asymmetric morphology reflection grating, when the incident angle is (-1) grade Littrow angle, (-1) grade diffraction efficiency which is higher than 95 percent can be obtained in a 80nm bandwidth range, the highest diffraction efficiency in the wave band is more than 99 percent, and the (-1) grade diffraction efficiency higher than 95 percent can be obtained in a wider angular spectrum, so that the grating can work in wider bandwidth and wider incident angle range. The broad-band high-diffraction-efficiency asymmetric morphology reflection grating has excellent performance and simple structure, is applicable to large-scale production, and has important application prospects in the field of high power laser.

The invention discloses a pure-phase spatial light modulator based on a metasurface. The pure-phase spatial light modulator comprises a lower substrate and an upper substrate, and the portion betweenthe upper substrate and the lower substrate is filled with a birefringent material with a dynamic phase modulation function; the lower substrate comprises a substrate with pixel point voltage modulation capability and a nano-structure array distributed on the substrate; the sizes and shapes of nanostructures in the nano-structure array are different, spatial distribution is uneven, the phase modulation amount generated by the nano-structure array can be changed by changing the geometric structure sizes of the nanostructures at different positions, and the static phase modulation function is achieved; phase modulation results of the birefringent material and the nanostructures are independent of each other; and an orientation layer is prepared in the surface, facing the birefringent material, of the upper substrate. The pure-phase spatial light modulator based on the metasurface effectively integrates a pixelated liquid crystal dynamic phase modulation function and a static phase modulation function of a nano-structure array metasurface.

The invention relates to a wavefront sensor based on a circular transmission area modified Hartmann mask and a detection method. The wavefront sensor comprises a diffraction element and a detector, wherein the diffraction element is a hybrid grating formed by a checkerboard phase grating and an amplitude grating with a circular transmission area. The modified Hartmann mask has a better diffractionspectrum characteristic, namely, higher +/-1-level diffraction efficiency, than a modified Hartmann mask (MHM) widely used at present when being applied to four-wavefront shearing interference, thereby further reducing system errors in differential wavefront extraction process, and improving the measurement accuracy; and the wavefront sensor simplifies the grating structure under the premise of ensuring the diffraction efficiency through properly selecting a quantification factor of the amplitude grating, and the processing difficulty of the components can be reduced. The wavefront sensor canbe applied to the field of high-precision wavefront detection.

A hologram recording material with high sensitivity, high diffraction efficiency, good storability, a small shrinkage ratio, dry processing applicability and a multiple recording performance, which is applicable to high density optical recording media and the like, is provided. The hologram recording material contains the specific acid generator of sensitizing dye.

A transmission grating that provides low polarization dependent loss over a wide wave range and provides high diffraction efficiency even with a small groove pitch and high resolving power and dispersion.

In a transmission grating 10, multiple parallel ridges 22 that are transparent for the wave range to be used are disposed on one side of a substrate 20 that is transparent for the wave range to be used. Parallel grooves 24 are formed at a fixed pitch a between these ridges. Light is applied from the surface of the transmission grating on which the grooves are formed and diffracted light is extracted from the substrate surface on which grooves are not formed. The groove pitch a is set to a range of 0.51 λc-1.48 λc, where λc is the central wavelength.

The invention discloses a three-dimensional microstructure inscribing system and method based on continuous laser. The three-dimensional microstructure inscribing system based on continuous laser comprises a continuous laser device, an acoustic-optical modulator, an objective lens, a photosensitive material and a three-dimensional nano displacement platform, wherein the continuous laser device is used for emitting laser light; the acoustic-optical modulator is used for adjusting the power of the laser light; the objective lens is used for focusing the laser light with the power being adjusted through the acoustic-optical modulator, so that a focused light beam is obtained, and the power density of the focused light beam is larger than the threshold power density obtained through two-photon absorption; the photosensitive material is subjected to two-photon polymerization under the effect of the focused light beam so as to be solidified, and thus two-photon polymerization direct-writing is achieved; and the three-dimensional nano displacement platform is used for carrying the photosensitive material and controlling the photosensitive material to move in the three-dimensional direction, and thus three-dimensional microstructure inscribing of the photosensitive material is achieved through layer-by-layer two-photon polymerization direct-writing of the photosensitive material. According to the three-dimensional microstructure inscribing system and method based on continuous laser, the low-cost laser continuous laser device is used as an inscribing light source, the power of the inscribing light source is adjusted through the acoustic-optical modulator, three-dimensional microstructure inscribing of the continuous laser device is achieved, and cost is reduced.

A non-linear optical device comprising a polymer configured to be photorefractive upon irradiation by a green laser. The polymer comprises a repeating unit including a moiety selected from the group consisting of the structures (M-1), (M-2) and (M-3), as defined herein.

A lens optical system is provided with a cemented lens element formed by cementing two constituent lens elements made of different optical materials together, with a diffractive optical surface formed at the cementing interface between the two constituent lens elements. The two constituent lens elements have at their respective interfaces with air a radius of curvature different from the radius of curvature that they have at the cementing interface.

The invention relates to an annular radiation type blazed grating which comprises an annular grating baseplate, blazed grating teeth (3) and diffraction surfaces (4), wherein the blazed grating teeth (3) are etched on the annular grating baseplate, and the diffraction surfaces (4) are positioned at one side of notched ridge lines (2) of the blazed grating teeth. The annular radiation type blazed grating is characterized in that the blazed grating teeth (3) are periodically arranged on the circumference of the annular grating baseplate, each blazed grating tooth (3) is in a radiation type, the projection of the upper surface of the annular grating baseplate is fan-shaped, and the bottommost parts of scale marks on the blazed grating teeth (3) are positioned on a plane (6); the diffraction surfaces (4) of the blazed grating teeth (3) are larger planes on one side of the notched ridge lines (2); and a plane formed from straight lines (11) and (12) perpendicular to the notched ridge lines (2) of the blazed grating teeth and the plane (6) intersect at a straight line (13), the straight line (13) and each diffraction surface (4) form a blaze angle (14), and the blaze angle (14) is unchanged for each blazed grating tooth. Compared with the prior art, the annular radiation type blazed grating has the beam deflection performance which other round or annular blazed gratings do not have, and the annular radiation type blazed grating is convenient to manufacture and has the characteristic of high diffraction effect. On the aspect of economic benefit, the annular radiation type blazed grating can be widely applied to occasions needing beam deflection, spectral analysis and the like, particularly to the deflection of revolving beams.