41 results about "Geometric phase" patented technology

In the context of array sensors such as radar, sonar, and communications receiver arrays, the present invention exploits the geometry phase components of radiated wavefronts associated with the signals of interest in order to reduce the bandwidth requirements for DOA and beamforming processing. Additionally, geometry phase is exploited in order to effectively increase the resolution of an array without changing the size of its physical footprint or the number of array elements. Other embodiments of the invention include the use of virtual array elements for increase in effective array size.

In the context of array sensors such as radar, sonar, and communications receiver arrays, the present invention exploits the geometry phase components of radiated wavefronts associated with the signals of interest in order to reduce the bandwidth requirements for DOA and beamforming processing. Additionally, geometry phase is exploited in order to effectively increase the resolution of an array without changing the size of its physical footprint. Other embodiments of the invention include the use of virtual array elements for increase in effective array size.

The invention relates to a building deformation monitoring method based on InSAR. The method includes the following steps that S1, InSAR original data is screened; S2, PS points are extracted and screened in a monitored region; S3, geometric phase positions of the PS points are removed; S4, the space deformation quantity of a building is solved; S5, according to the solved deformation quantity, the gradient of the building is calculated; S6, monitoring is carried out on time dimension, the steps are repeated, a monitoring differential value is obtained, and the deformation quantity and deformation rate of the building are obtained. By the utilization of the InSAR technology, the deformation field of the building in the direction of a radar sight line is obtained, spatial interpolation is carried out on pixels in the deformation field in the direction of the radar sight line, wherein the coherence of the pixels is lower than an untwisting threshold value, and therefore a spatial continuous deformation field is obtained; by processing and calculating obtained data, the deformation and deformation rate of the building are obtained. The method is large in range and low in cost and easily monitors the building for a long term during monitoring of the building, and can effectively make early warning for accelerated deformation of the building.

A method of measuring overlay error comprises forming a first mask having a first alignment array comprising a periodic pattern of first features having a first periodicity, forming a second mask having a second alignment array comprising a pattern of second features having the first periodicity, the first alignment array being adjacent the second alignment array, the first alignment array and the second alignment array forming a combined alignment array, transforming the combined alignment array to produce a transformed array, selecting a first region within the transformed array, inverse transforming the region to produce geometric phase shift information, averaging the phase shift information, converting the averaged phase shift information into a value for misalignment in a first direction corresponding to the first region, repeating the selecting, inverse transforming, averaging and converting using a second region within the transformed array to calculate a value for misalignment in a second direction corresponding to the second region, calculating an overlay error between the first and second mask levels by adding the components of misalignment in the first direction and second direction.

The invention discloses a dielectric geometric phase metasurface structure material with a low depth-to-width ratio and a structural optimization method thereof. The dielectric geometric phase metasurface structure material comprises a substrate, a reflecting layer on the substrate, a multi-beam interference layer on the reflecting layer and a dielectric nano brick array formed by periodically arranging a plurality of dielectric nano bricks with consistent sizes on the multi-beam interference layer, wherein the dielectric nano brick array is used for receiving perpendicularly incident circularly polarized light and adjusting the phase of the emergent light through adjusting the direction of each dielectric nano brick. The depth-to-width ratio of the dielectric geometric phase metasurface structure material is reduced to half of the depth-to-width ratio of the traditional transmission-type metasurface material, and the depth-to-width ratio is about 1.7, so that the requirements for theprocessing technology are reduced, and the finished product rate and mass production of the device are guaranteed.

The invention provides an adjustable broadband polarization conversion and dynamic geometric phase modulation device based on phase change material, comprising a metal reflecting layer, a phase changematerial layer, a dielectric isolation layer and a super surface structural layer sequentially from bottom to top. The design of the polarization conversion and geometric phase modulation device is carried out based on the phase change material; optical material parameters of the phase change material, such as crystal state and dielectric constant, are changed by means of electric excitation, optical excitation and thermal excitation; dynamic modulation of polarization conversion is achieved within a broad band range; accordingly, designs of a novel functional device, such as adjustable beamdeflection, plate lens, and calculation of holographic and orbital angular momentums. A method of the invention may provide further improved ability of electromagnetic modulation of super surface, anda new idea and technical scheme are provided for the design of novel adjustable-function electromagnetic modulation elements.

The invention discloses a broadband achromatic device based on a medium super-surface, relating to the field of new artificial composite material super-surfaces. The device comprises a device body, the device body comprising a dielectric rectangular block positioned on an upper layer and a substrate positioned on a lower layer. The achromatic analysis thereof comprises the steps of using a mannerof combining a geometric phase with a propagation phase to respectively control wavefront of an incident left-handed circularly polarized light and eliminate chromatic aberration; then performing sizetrimming to construct a super-surface array; and realizing analysis on the achromatic characteristic of the device body by extracting and processing right-handed circularly polarized energy of a detection surface. On one hand, the broadband achromatic device in the invention utilizes a method of combining two phases; and on the other hand, realizes achromatic in a continuous bandwidth range, thereby greatly reducing volume and cost thereof as compared with a past device.

The invention discloses a non-commutative quantum geometric phase NV color center gyroscope which comprises an angular rate sensing unit (3). The angular rate sensing unit comprises a shielding box shell (303), a laser entrance port (305) is formed in the shielding box shell, and a triaxial Helmholtz coil (307) is mounted in the shielding box shell through a coil base (308); diamond (302) with a cluster NV color center is mounted in the triaxial Helmholtz coil through a diamond support (309), a microwave-radio frequency antenna (301) is mounted on the diamond support, and photodiodes (311) are mounted at the position, around the diamond, of the diamond support. The atomic excitation, quantum manipulation and other advanced technologies are applied, the NV color center energy level is regulated and controlled under the action of laser, an applied magnetic field, microwaves and radio frequency, the frequency locking technology is utilized for detecting frequency transition, fluorescence number and layout changes are used for collecting and reading, and the high-performance non-commutative quantum geometric phase NV color center gyroscope is developed.

The invention discloses a geometric phase metasurface applied to broadband multi-mode vortex wave beam generation. A basic unit of the metalsurface is composed of a metal rod structure, a dielectric layer and a metal backboard stacked successively from top to bottom. The unit is anisotropic via special structural design, and the reflection phase difference is 180 degree under x and y polarized electromagnetic wave irradiation. A metal rod rotates for an angle phi within the horizontal plane of the metasurface by taking the center of the metal rod itself as the origin, and circular polarized incident waves irradiated on the unit is reflected to obtain circular polarized waves with the same rotation performance plus an additional +/- 2phi geometric phase change. The units are arranged in a 2D plane according to preset phase distribution, and under irradiation of the circular polarized electromagnetic waves, the metasurface can generate four different modes of vortex wave beams in different directions. The metasurface is simple in structure, easy to process and wide in working frequency band, and can be used for information coding, and the channel capacity can be improved by mode multiplexing.

The invention discloses a large view field super resolution imaging device which comprises a base and a super-surface, wherein the base and the super-surface are successively arranged in the bottom-up sequence. The super-surface is composed of nano-unit structure arrays which are arranged in succession on an ultra-thin metal or a dielectric film. A nano-unit structure is a deep sub-wavelength structure. According to the invention, geometric phase on the nanostructure is used to control the electromagnetic wave symmetry; electromagnetic waves are converted from rotation symmetry to translational symmetry to acquire large view field perfect focusing near 180 degrees; if curved face or multi-plane combination is used, large view field imaging can be realized; the work bandwidth can cover the entire electromagnetic spectrum; the resolution is close to or even beyond the diffraction limit; and the device has a wide application prospect in the field of large view field super resolution imaging.

The invention discloses near-eye display apparatus and equipment, a zooming module and a zooming method, for solving the technical problem that a current display device is lower in the zooming effect.The near-eye display apparatus comprises a display module, a zooming module and a near-eye display slab waveguide, wherein the display module, the zooming module and the near-eye display slab waveguide are arranged along the optical path successively; the zooming module comprises an electrode unit and overlapped multi-layer PBLs (Pancharatnam Berry Lens); the electrode unit is used for applying/not applying voltage to the PBLs; each layer of PBL is an optical component which is made of liquid crystal and is based on geometric phase adjustment, and each layer of PBL has one focal power when novoltage is applied; during the projection process, the display module is used to emit circularly polarized light corresponding to an image to be displayed; the zooming module is used to receive the circularly polarized light and control the electrode unit to apply no voltage to N layers of PBLs according to the required focal power; and the total focal power of the N layers of PBLs is corresponding to the required focal power, and when N is greater than or equal to 2, the N layers of PBLs are continuous, and the near-eye display slab waveguide is used to import the light emitted from the zooming module into a human eye.

A self-interference digital holographic system obtains interference patterns of incident light using a simple geometric phase lens, and obtains a holographic image of a target object using the interference patterns. The self-interference digital holographic is fabricated simply in a low cost and in a miniaturized size, and the use thereof as actual products is extended to a wide range of applications. The phase of incident light is be changed by rotating a polarizer, independently of a change in the optical path. Phase-shifting effects are obtained with fewer errors in all wavelength ranges, and a more accurate holographic image is produced. A single birefringence hologram is obtained by a one-time image-capturing process by simultaneously forming interference patterns from phase-shifted linearly-polarized beams by space division, using a phase shifter on the basis of space division. Moving holographic images can be captured.

An embodiment of the invention relates to the technical field of information processing, and discloses a dynamic modulation method for a phase of a terahertz wave. The method comprises the following steps that a predesigned modulation pattern is generated by utilizing a spatial light modulator; pump light is irradiated on a semiconductor through the modulation pattern, and carrier distribution isgenerated on the semiconductor; the carrier distribution generates electric conductivity distribution, so that the semiconductor has metallic properties; and an initial terahertz wave irradiates the semiconductor, and the phase is modulated by the semiconductor to obtain a target terahertz wave, wherein the modulation pattern comprises a plurality of structural units which are arranged in a discrete manner. According to the embodiment, the different modulation patterns are dynamically generated, so that a pure-phase dynamic modulation metasurface for the terahertz wave is realized, the modulation pattern adopts a geometrical phase modulation method, the modulation mode is simple, the modulation effect is stable, and continuous, fast and accurate modulation of the phase is realized while the same amplitude modulation is guaranteed.

The invention discloses a method for jointly detecting and repairing a cycle slip by an MW combination method and a non-geometric phase method. The method comprises the following steps of S1, selecting three-frequency data (B1, B2 and B3) of a Beidou navigation and positioning system to obtain a pseudo-range observation value and a carrier phase observation value; S2, constructing a three-frequency MW combined observation model, establishing a MW equation, and carrying out inter-epoch difference to obtain cycle slip detection amount delta N12 and delta N13; S3, constructing a non-geometric phase observation model; S4, selecting two groups of parameters according to a principle that an ionized layer coefficient and the observation noise of the combined observation data are relatively smallat the same time, calculating the cycle slip of the three frequency points of the two groups of the parameters according to a formula that delta N1 is equal to delta N2 that is equal to delta N3, andselecting a B combination coefficient meeting the actual situation; and S5, combining the delta N12, the delta N13 and the B combination to obtain an equation set, calculating the cycle slip on the three frequency points, and repairing the cycle slip. The method solves the defect that the non-geometric method cannot detect the non-sensitive cycle slip and the MW method cannot detect the equal cycle slip.

The invention provides a non-linear phase gradient metasurface based on rotation crystal direction. The non-linear phase gradient metasurface comprises C3 and C5 sub-wavelength metal holes or slits with higher-order rotation symmetry. According to the nonlinear phase gradient metasurface, a selection rule of a conventional geometric phase metasurface unit structure is broken through, and the singular nonlinear geometric phase gradient is obtained in a linear optical system through design of the triangular, Y-shaped and pentagonal sub-wavelength metal holes or slits with multi-rotation symmetry; the phase gradient is different from the conventional nonlinear phase, the conventional nonlinear phase usually refers to the phase carried by higher-order harmonic waves (n>=2), and the generated phase gradient is from fundamental waves (n=1); and according to the non-linear phase gradient metasurface, the nonlinear phase gradient is realized in the linear metasurface, the cognition of the geometric phase in the linear metasurface for people is overthrown, and a great significance is attached to the principle and application of phase modulation in the linear optical system.

The invention provides an artificial grid making geometric phase analysis method based on local high-resolution Fourier transformation. The method comprises the following steps of firstly collecting an undeformed raster image and a deformed raster image; respectively performing fast Fourier transformation on a reference image and a deforming image; acquiring a reference spatial frequency spectrum and a deformation spatial frequency spectrum, and selecting the interval where a spatial frequency main value is positioned to perform the local high-resolution Fourier transformation to obtain a local high-resolution spatial frequency spectrum; determining the spatial frequency main value in the local high-resolution spatial frequency spectrum and taking the spatial frequency main value as a center to select a spatial frequency value; filtering on the spatial frequency spectrum formed by the selected spatial frequency value so as to obtain a filtering reference spectrum and a filtering deformation spectrum, and then performing Fourier inversion and solving a reference phase and a deformation phase; and solving a phase difference by using the reference phase and the deformation phase, and calculating displacement and strain. The displacement and strain result calculated by the method is high in precision and short in calculation time.

The invention relates to the technical field of optics, discloses a vision correction device, and aims at solving the inherent defects of the traditional vision correction device such as thick and heavy device and aberration. The device comprises a common optical axis linear polarizer, a geometric phase lens and a 1/4 wave plate which is arranged between the linear polarizer and the geometric phase lens. The geometric phase lens realizes the beam diffraction and deflection by controlling the change of the long-axis direction of the birefringent material corresponding to each ring with the optical axis as the center so as to realize the convergence of the same-order diffracted beam equal to the non-zero diffracted beam by the convex lens with the real focus and/or divergence of the same-order diffracted beam equal to the non-zero diffracted beam by the concave lens with the virtual focus.

The invention relates to a method for operating a laser device, comprising the steps: a) providing a laser pulse (110) in a resonator (1) so that the laser pulse (10) circulates in the resonator (1), the laser pulse (10) having a carrier wave (120); b) determining an offset frequency (f0) of the frequency comb corresponding to the laser pulse (110), the frequency comb having a plurality of laser modes (fm) at a distance (frep) from one another, the frequencies of which can be described by the formula: fm = m * frep + f0, m being a natural number; and c) varying the offset frequency (f0) by varying a geometric phase ([delta][phi]) that is impressed on the carrier wave (120) of the laser pulse (110) per resonator revolution.