753 results about "Phase plate" patented technology

A phase plate including a plurality of surfaces arranged around a symmetry axis to reflect an incident electromagnetic field having a null orbital angular momentum, thereby generating a reflected electromagnetic field having an orbital angular momentum. The surfaces are arranged such that, with respect to a cylindrical reference system in which the azimuthal coordinate is measured in a plane perpendicular to the symmetry axis, the respective heights define a non-monotonic azimuthal profile, so that the reflected electromagnetic field forms an optical vortex whose topological charge is not associated one-to-one to the orbital angular momentum.

The present invention provides a phase correction element which can be used for recording and/or reproducing an information of three types of optical disks for HD, DVD and CD by employing a single objective lens for HD, and an optical head device.

The phase correction element 100 of present invention comprises a first phase correction layer 10A formed in a region of numerical aperture NA₂, and a first phase plate 30A integrally formed; the first phase correction layer 10A comprising a concavo-convex portion having a rotational symmetry with respect to the optical axis of incident light and having a cross-sectional shape of a saw-tooth-form or a saw-tooth-form whose convex portions are each approximated by a step form; the first phase plate 30A generating a birefringent phase difference of about an odd number times of π/2 for linearly polarized light having a wavelength of λ₁; and the phase correction element 100 having a function of not changing a transmitted wavefront of the wavelength of λ₁ and changing a transmitted wavefront of the wavelength of λ₂ or transmitted wavefront of both wavelengths of λ₂ and λ₃ when three types of incident light in a λ₁=410 nm wavelength band, a λ₂=650 nm wavelength band and a λ₃=780 nm wavelength band respectively, are incident.

The invention discloses a system and a method for preparing a micro-pore array through femtosecond laser direct writing. The system comprises a femtosecond vector light field generation system, a spatial filtering component, a computer and a three-dimensional mobile platform, wherein a 1/2 wave plate, a Glan-laser polarizer, a beam expander and the femtosecond vector light field generation system are arranged on an output straight light path of a femtosecond laser device in sequence; a 4f system is arranged on a light path behind a reflective pure phase spatial light modulator after a holographic phase plate is loaded; a spatial filter is arranged on a frequency spectrum surface; and positive and negative levels of diffraction light which pass through the spatial filter pass through a 1/4 wave plate respectively and are combined into a beam of laser through a Rochi grating. A material is adjusted to a focal position through the spatial filtering component, an electronic diaphragm, a focusing lens and the three-dimensional mobile platform; and the spatial light modulator, the electronic diaphragm and the three-dimensional mobile platform are connected with a computer through data lines. The device has the advantages of simple structure, convenience in operation and capabilities of preparing the micro-pore array with various patterns and improving the machining efficiency.

In a dark environment, when a backlight 119 is lighted, white light emitted from the surface of a light guide plate 118 passes through a polarizing plate 107 and a phase plate 108 and, further, passes through a transflective plate 111 and a transparent electrode 116 provided on the inner surface of a substrate 102 before it is introduced into a liquid crystal layer 3. Then, it is guided to the exterior of a liquid crystal cell and sequentially passes through a phase plate 106 and a polarizing plate 105 before it is guided to the exterior. In a bright environment, external light incident from the polarizing plate 105 passes through the liquid crystal layer 3, and is then reflected by the transflective plate 111 through the transparent electrode 116 before it is passed through the polarizing plate 105 again and guided to the exterior.

Orbital angular momentum (OAM) communications systems provide an additional degree of freedom to the electromagnetic waves that travel between the transmission and receiving stations, thereby enabling a dramatic increase in data transmission rates. The present invention provides a design for a very low reflectivity flat spiral phase plate that generates OAM modes and a method of making the same. The design incorporates variable sizes of perforated unit cells and may include matched layers to provide improved impedance matching, and the flat disc shape makes the phase plate compact and easy to install. The OAM phase plate can be designed to operate at frequencies from a few 100s KHz to ultraviolet frequencies and is capable of providing one or more OAM modes at the operational frequencies, irrespective of polarization. In a preferred embodiment, the OAM phase plate is designed for operation at about 30 GHz frequency, with 20 GHz bandwidth.

The invention discloses a multi-mode microimaging method based on programmable LED array illumination. An LED array used as an illumination light source of a microimaging system is directly installed below a sample carrying bench of the microimaging system and the center of the LED array is located at an optical axis of the microimaging system, thereby realizing phase contrast, optical field imaging, and optical dyeing imaging modes. With the method, dyeing microimaging can be realized flexibly and no additional optical element like an annular diaphragm, a microlens array, and a phase plate and the like needs to be added in an imaging light path of a microscopic, so that the system structure is simplified and the cost is substantially reduced.

The invention relates to a method for the production of a multilayer electrostatic lens arrangement with at least one lens electrode in general, a method for the production of a phase plate in particular as well as the lens arrangement, the phase plate and a transmission electron microscope with the phase plate.

The lens arrangement or the phase plate is produced from a thin self-supporting silicon nitride membrane which is fixed in a macroscopic chip with deposition of further layers. beam.

The central bore as well as the aperture opening are milled out by means of an ion

The invention discloses a naked eye three-dimensional display device based on an active emitting type display technology. The device comprises an active emitting display unit, wherein the display unit comprises an emitting array adjustable in light strength, and according to multi-visual-angle superposed images, the emitting array modulates a light field amplitude through a circuit control system; and a directive phase plate, wherein the pixels of the directive phase plate contains nano-grating pixel structures which are respectively corresponding to sub-pixels of the visual-angle images, the nano-grating pixel structures contains nano-grating combinations which are designed according to a holographic principle, the nano-grating pixel structures carry out wavefront conversion on incident visual-angle images after light emitted by the active emitting display unit is irradiated to the directive phase plate, and a convergence viewpoint of parallel illumination light is formed in the space in front of or at the side surface of the active emitting display unit. Compared with the prior art, the demands of personal consumption electronic markets and industrial and outdoor display markets are simultaneously met, and naked eye three-dimensional display which is ultra-thin, convenient, large in area, high in brightness and low in cost is realized.

The invention discloses a birotor fault simulation experiment device. Based on a gas turbine birotor test bed, a movable-static rubbing support with a force sensor, a movable-static rubbing block, a movable-movable rubbing adjusting bolt with an adjustable gap and the like are used for simulating a rotor rubbing fault and measuring the impact force in the horizontal direction. Fine-grained metal chips are filled into a bearing lubricating cavity to simulate a bearing abrasion fault. Stainless gap pieces with different thicknesses are combined with a bearing block, and a rotor misalignment fault is simulated. Through a positioning hole and a mass block of a wheel disc and matching of a bonded phase plate, a mass unbalance fault of a rotor with the adjustable mass and phase is simulated. A disc-shaped spring and a bearing block are used for simulating a looseness fault of the bearing block with the adjustable looseness. The birotor fault simulation experiment device can be used for simulating the faults of rotor rubbing, bearing abrasion, rotor misalignment, rotor mass unbalance and bearing block looseness of a gas turbine birotor system, the accuracy of fault analysis of the gas turbine birotor system is improved, and experiment reference data are provided for simulation calculation.

The invention discloses a system for generating a radial Bessel-Gaussian beam. The system comprises a beam expander, a computer-controlled spatial light modulator, a vortex phase plate and a radial polarization convertor that are sequentially arranged in a light direction of a light source generating linearly polarized light, wherein a topological charge of the vortex phase plate is 1; and a calculation hologram generated by a computer is loaded to the spatial light modulator to form a calculation holographic grating, so that a first order Bessel-Gaussian beam is generated. The vortex phase plate is rotated to ensure that phase structure distribution of the vortex phase plate is right opposite to the phase structure distribution of the Bessel-Gaussian beam coming out of the spatial light modulator, and a vortex phase of the Bessel-Gaussian beam is eliminated. Then, the Bessel-Gaussian beam with the vortex phase being eliminated passes through the radial polarization convertor. Radial polarization Bessel-Gaussian beams with different ring numbers can be generated by generating different holograms due to the flexibility of the holograms of the computer, and have self-restorability.

It is an object of the present invention to provide a light source unit that can supply bright light efficiently. The light source unit includes a light emitting unit that emits light, a phase plate that polarizes the light from the light emitting unit to produce a first polarized light and a second polarized light that is polarized in a different direction with respect to the first polarized light, a reflecting-type polarizing plate that transmits the first polarized light and reflects the second polarized light; and a reflector that is provided near both the light emitting unit and the phase plate, and reflects back a third light, which is a portion of the first polarized light and that passes through the phase plate, to the phase plate.

A transmissive phase plate with a function of correcting direction of polarization of light rays in an incident divergent or convergent light flux in addition to functions as a wave plate. Conditions of polarization of incident light rays are corrected by a polarization-correcting optical multi-layer coating which is formed by alternately depositing a high refractivity layer and a low refractivity layer on curved substrative surface of a predetermined radius of curvature. The transmissive phase plate can be applied to correct conditions of polarization of incident light rays of a polarized beam splitter for the purpose of improving contrast ratio of a projection display.

Motion of an object of interest, such as a cell, has a variable velocity that can be varied on a cell-by-cell basis. Cell velocity is controlled in one example by packing cells into a capillary tube, or any other linear substrate that provides optically equivalent 360 degree viewing access, so that the cells are stationary within the capillary tube, but the capillary tube is translated and rotated mechanically through a variable motion optical tomography reconstruction cylinder. The capillary tube motion may advantageously be controlled in a start-and-stop fashion and translated and rotated at any velocity for any motion interval, under the control of a computer program. As such, there are several configurations of the optical tomography system that take advantage of this controlled motion capability. Additionally, the use of polarization filters and phase plates to reduce light scatter and diffraction background noise is described.

The invention discloses an image encryption method based on double random phase encoding and an interference principle. The image encryption method based on the double random phase encoding and the interference principle comprises the following steps of encryption and decryption. In the encryption step, two images are respectively used as a to-be-encrypted image and an image of a phase plate with false contouring information, the to-be-encrypted image is encrypted by applying the phase plate with the false contouring information and a random phase plate, an encryption result is decomposed into two phase plates by utilizing the interference principle, and random permutation of elements between the two phase plates is realized by a numerical method. In the decryption step, Fourier transformation is performed after two phase plates finally obtained by the encryption are superposed, inverse Fourier transformation is performed after a Fourier transformation result is multiplied by the phase plate with the false contouring information, and the amplitude of the phase plate is extracted to obtain an original image. The method disclosed by the invention is used for the encryption and the decryption of the images. The phase plates obtained by the encryption do not have the outline show problem of the original image. The false contouring information is introduced into the method, so that not only is an effect of misleading attackers exerted but also a basis is provided for legal decoders to select the phase plate on a frequency spectrum surface.

The invention belongs to the field of integrated optoelectronics and optical communication, and relates to an integrated orbital angular momentum mode transmitter. The integrated orbital angular momentum mode transmitter is constructed by integrally growing a substrate, a reflecting mirror structure, an active region, a transverse optical field and electric field limiting layer and a phase plate generating angular spiral phase distribution, thereby forming an independent integrated device. The phase plate generating angular spiral phase distribution can be a structured phase plate having a spiral continuous phase plate structure, a spiral stepped phase plate structure, a fork-shaped diffraction grating phase plate structure and a super-surface phase plate structure capable of providing spiral phase distribution along the angular direction. By adopting the integrated orbital angular momentum mode transmitter, high integration and miniaturization are realized, the device process is mature, and the structure is simple and is easy to realize. The wavelength of the angular momentum mode of a transmission orbit can be flexibly changed through selection of the structural parameters of a reflecting mirror as well as the material system and structure of an active layer. The integrated orbital angular momentum mode transmitter plays an important role in promoting the development of rapid orbital angular momentum optical communication.

A laser microscope according to an embodiment of the invention includes: a laser beam source; a phase plate providing a phase difference for laser beam from the laser beam source in accordance with an incident position; an objective lens focusing light transmitted through the phase plate onto a sample; a first separating unit separating second harmonic light emitted from the sample in a direction opposite to a traveling direction of the laser beams from a fundamental light reflected by the sample; and a photodetector detecting the second harmonic light separated from the fundamental light by the first separating unit.

The invention discloses a generation system and a generation method for a spinning-orbital angular momentum hybrid entangled state. The system consists of a single photon source, a spinning-orbital angular momentum conversion unit, a spinning-orbital angular momentum hybrid entangled state separation unit and a feedback compensation unit, wherein the spinning-orbital angular momentum hybrid entangled state separation unit obtains spinning-orbital angular momentum hybrid entangled state photons through a polarization beam splitter, a polarization controller and a Q-plate phase plate; the separation unit realizes separation of horizontal polarization single photons from the spinning-orbital angular momentum hybrid entangled state photons through two beam splitters, two full reflectors and two dove prisms; the feedback compensation unit feeds back and transmits non-converted horizontal polarization light to the spinning-orbital angular momentum conversion unit for further conversion. The generation system disclosed by the invention realizes high-efficiency conversion of a high-purity spinning-orbital angular momentum hybrid entangled state, so that the system cost and the communication error rate are reduced, and the security of the system is enhanced.

An electron microscope according to the present invention includes a phase plate (510) having a thickness which changes in a radial direction, and adjusts a phase difference caused by a difference in electron beam path due to an effect of a spherical aberration when an electron beam is converged by a lens or an image of the electron beam is formed. Accordingly, the phase difference caused by the difference in electron beam path is adjusted, to thereby improve the coherence, so that a phase contrast image of transmitted electrons can be obtained at a higher resolution.

Light-emitting devices and light-emitting displays for realizing bright display by allowing light emitted from an emissive layer to efficiently contribute to a display. Polarization separators are arranged between the emissive layer and a phase plate. In the light of a wavelength range which includes a part or all of a light-emission wavelength range of the emissive layer and is narrower than a visible wavelength range and is directed from the emissive layer side to the polarization separators side, the polarization separators reflect circularly polarized light components which are converted into linearly polarized light that is absorbed by the polarizer due to the operation of the phase plate and transmit the other light.

An X electrode (18) is provided on a surface of a phase plate (15) which surface faces a liquid crystal panel (10). A Y electrode (19) is provided on a surface of a polarizing plate (17) which surface faces the liquid crystal panel (10). This makes it possible to provide a display device that has a touch function and can reduce a thickness and improve display quality.

The present invention provides an on-chip thin film phase plate for a releasing charging, comprising a chip substrate having one or more apertures; and a thin film layer attached to the top surface of the chip substrate. The present invention also provides a method for observing organic material by TEM, which uses the above-mentioned on-chip thin film phase plate in a TEM system.

New methods for phase contrast imaging in transmission electron microscopy use the imaging electron beam itself to prepare a hole-free thin film for use as an effective phase plate, in some cases eliminating the need for ex-situ fabrication of a hole and reducing requirements for the precision of the ZPP hardware. The electron optical properties of the ZPP hardware are modified primarily in two ways: by boring a hole using the electron beam; and/or by modifying the electro-optical properties by charging induced by the primary beam. Furthermore a method where the sample is focused by a lens downstream from the ZPP hardware is disclosed. A method for transferring a back focal plane of the objective lens to a selected area aperture plane and any plane conjugated with the back focal plane of the objective lens is also provided.