137 results about "Surface grating" patented technology

The invention relates to a metamaterial structure for modulating a terahertz wave, comprising a central medium layer, an upper surface grid layer and a lower surface grid layer. The central medium layer is made of a polyethylene materials transparent to the terahertz wave and has a thickness smaller than the one-tenth wavelength of an incident terahertz wave; the upper surface grid layer adopts metal material and comprises a series of parallel grids periodically distributed on the upper surface of the central medium layer; each grid and gaps at both sides of the grid form a period, and the thickness of each grid is smaller than the width thereof; the lower surface grid layer adopts a metal material and comprises a series of parallel grids periodically distributed on the lower surface of the central medium layer; each grid and gaps at both sides of the grid form a period,, and the thickness of each grid is smaller than the width thereof; and the grids of the upper surface grid layer and the lower surface grid layer are symmetrically distributed in a mirror mode. The invention has the advantage that the modulation range of the terahertz wave is widened by a modulator because the transmission of the terahertz wave is constantly enhanced by a surface plasma wave.

Methods for realizing integrated lasers and photonic integrated circuits on complimentary metal-oxide semiconductor (CMOS)-compatible silicon (Si) photonic chips, potentially containing integrated electronics, are disclosed. The integration techniques rely on light coupling with integrated light coupling elements such as turning mirrors, lenses, and surface grating couplers. Light is coupled from between two or more substrates using the light coupling elements. The technique can realize integrated lasers on Si where a gain flip chip (the second substrate) is bonded to a Si chip (the first substrate) and light is coupled between a waveguide in the gain flip chip to a Si waveguide by way of a turning mirror or grating coupler in the flip chip and a grating coupler in the Si chip. Integrated lenses and other elements such as spot-size converters can also be incorporated to alter the mode from the gain flip chip to enhance the coupling efficiency to the Si chip. The light coupling integration technique also allows for the integration of other components such as modulators, amplifiers, and photodetectors. These components can be waveguide-based or non-waveguide based, that is to say, surface emitting or illuminating.

The invention designs an immediate-shooting immediate-display multi-lens digital stereoscopic system. The system consists of a stereoscopic shooting system and a stereoscopic display system jointly, and concretely comprises a plurality of CCD camera units (1), a platform (2) for fixing the CCD camera units, a bracket (3) for supporting the platform, an image acquisition card (4), a power source (5), a PC (6), a cylindrical-surface grating-type or slit-type naked-eye free stereoscopic display (7) and the like. The stereoscopic system adopts a camera calibration method to initially adjust the spatial position relation of the CCD camera units and calculate the distortion coefficients of camera lenses, corrects the geometric distortion of images according to the distortion coefficients, adopts epipolar geometry to correct trapezium distortion caused by camera layout, and then adjusts unreasonable parallax in multipath acquisition. Through the combination of the methods, the stereoscopic system can shoot not only static scenes, but also dynamic scenes, enables a shooting process to be simpler, convenient and flexible, and can realize shooting-displaying synchronization.

The invention relates to a wide spectrum metal dielectric film grating and an optimization method thereof; the grating comprises a substrate, a metal Ag film, a multi-layer dielectric film, a residual film layer and a surface grating structure; and every layer of dielectric reflective film comprises a SiO2, a HfO2 and a TiO2 dielectric films. The method first defines a grating diffraction efficiency spectral property value evaluation function, selects the refractive index of metal media and a plurality of layers of dielectric film materials as well as the grating parameters which are optimized, and builds a wide spectrum metal dielectric film grating TE wave diffraction efficiency value analyzing model according to a strict coupled-wave theory. Through the optimization of a plurality of parameters, the obtained grating cycle is 1480lines/mm, the groove depth is 290nm, the thickness of the residual film layer is 10nm, the duty cycle is 0.28, and an incident angle is 60 degrees. According to the invention, when TE polarized light with the wavelength being 1053nm enters, the diffraction efficiency of the wide spectrum metal dielectric film grating in a wide spectrum bandwidth being more than 190nm in the -1 grade direction of reflection diffraction is over 97 percent.

The invention relates to a light-emitting diode (LED) light source which produces light through a semiconductor band gap structure, in particular to an electromagnetic wave transmission structure, namely an active polarized light emission optical device with a composite micro-nano surface grating structure. The LED comprises a substrate (1), an n-type layer (2), a quantum well (3), a p-type layer (4) and a metal grating (6) and is characterized in that: a composite structure of a medium transition layer (5) and the metal grating (6) is plated or etched on the upper surface of the p-type layer (4); the refraction index of the medium transition layer meets the conditions that: n is greater than 1.0 and less than the refraction index of the p-type layer medium (4); and the transition layer is one of a thin film structure, a grating structure and an embedded structure. Due to the adoption of the structure, the transmission and extinction characteristics of the LED can be enhanced effectively; and in a period, the flatness of the side face of the grating, the duty ratio of the grating, and the range of working wavelengths are obviously improved compared with those of a conventional single-layer metal grating.

A surface grating coupler for polarization splitting or diverse includes a planar layer and an array of scattering elements arranged in the planar layer at intersections of a first set of concentric elliptical curves crossing with a second set of concentric elliptical curves rotated proximately 90 or 180 degrees to form a two-dimensional (2D) grating. Additionally, the grating coupler includes a first waveguide in double-taper shape and a second waveguide in double-taper shape respectively for split or diverse an incident light into the 2D grating into two output light to two output ports with a same (either TE or TM) polarization mode or one output port with TE polarization mode and another output port with TM polarization mode. The polarization diverse grating coupler is required to test multiple polarization sensitive photonics components and can be used with other single polarization grating coupler via a fiber array to perform wafer-level testing.

The invention provides a method for converting an evanescent wave into a traveling wave. The method is implemented by the aid of a super-surface grating formed by a polarization independent nano-brickarray. Size parameters of the length and the width of a nano-brick are adjusted, a phase gradient is designed, the super-surface grating is constructed, different transverse wave vector variation ofpolarized incident light waves along the directions of a long axis and a short axis of the nano-brick can be achieved, so that the evanescent wave is converted into the traveling wave, the traveling wave is transmitted to a far field, and super-resolution imaging is achieved. The super-surface formed by the nano-brick array has the advantages of high integration and transmittance, relatively simple machining process and the like and is applied to the fields such as biomedicine microscopy imaging, optical lithography and ultrahigh-density optical memory.

The invention discloses a broadband angle selection laser filter, which comprises a first surface grating used for performing first diffraction on incident laser, and a Bragg grating for performing second diffraction on diffraction light transmitted from the surface grating, wherein the grating period of the surface grating is two times that of the Bragg grating. The broadband angle selection laser filter is fundamentally different from the traditional spatial filter which employs a lens and a pin hole, and the laser filter is compact in structure; the filter is wider in diffraction spectrum,has excellent low-pass filtering capacity on various spectral components, and can meet the requirement of short pulse and ultra-short pulse laser spatial filtering; and the bearable laser power is higher, and the possibility of causing a plugged hole effect and burning a filter component due to focused laser is eliminated.

The invention relates to a 3D display device, in particular to a multi-viewpoint 3D display device. The multi-viewpoint 3D display device comprises a 3D display device body, the 3D display device body comprises a projection screen and a projection unit, and the projection unit comprises at least three projectors for showing different viewpoint scenes. The projectors project to the projection screen which is a transmittance type diffuser screen with different projection angles, and a cylindrical surface grating is arranged on the light-emitting face of the transmittance type diffuser screen. The transmittance type diffuser screen with different projection angles is adopted for being combined with the projectors for showing different viewpoint scenes, in this way, pictures shown by the projectors for showing different scenes are projected in different directions through the transmittance type diffuser screen, and then people can enjoy different pictures from different viewpoints.

The invention discloses a novel nitride quantum well infrared detector and a manufacturing method thereof. According to the quantum well infrared detector, a mask layer on a substrate is provided with hole structures distributed periodically, nanopillar arrays grow from holes, multiple quantum wells grow on the tops and the side faces of the nanopillar arrays, the multiple quantum wells corresponding to the tops are semi-polar face multiple quantum wells, and the multiple quantum wells corresponding to the side faces are nonpolar face multiple quantum wells. The multiple quantum wells grow on the nanopillar arrays with extremely low dislocation density, so a multiple quantum well structure with extremely high crystal quality can be achieved; the polarized field intensity of the semi-polar face multiple quantum wells and the nonpolar face multiple quantum wells is far below that of traditional polar face multiple quantum wells, so extraction of efficient photo-electric signals can be achieved; photoelectric responses occur on the surface of the front incidence detector, and the process of manufacturing a surface grating structure for a traditional quantum well infrared detector or conducting end face 45-degree polishing on the traditional quantum well infrared detector is omitted; third-generation semiconductor materials are adopted for multiple quantum well materials, photon detection of a full infrared spectroscopy window can be achieved, and application prospects are broad.

The invention discloses a single-mode laser based on high-order surface gratings. The laser is of a ridge waveguide structure, and comprises a covering layer, a core layer and a substrate in a transverse direction. Narrow-groove-width high-order Bragg gratings are etched on a front segment ridge waveguide surface close to the output end of the laser, the etching depth of the group of gratings does not penetrate through the core layer, and optical feedback of the laser at the output end is provided; and a rear segment ridge waveguide of the other end of the laser does not contain gratings, an end face of the end is a deeply-etched interface, and optical feedback of the laser at the end is provided. The single-mode laser does not need secondary epitaxial growth of a material, and the manufacturing process is simple and convenient, thereby reducing the manufacturing cost of a device, and improving the reliability of the device; through introduction of the narrow-groove-width high-order surface gratings, radiation loss of the gratings is reduced, and laser performance is improved; and the laser rear end face formed by a deep etching method is easy to accurately position, the problem that the cavity length is indeterminate which is generated due to cleavage of an end face is avoided, and the laser is guaranteed to have good single-mode characteristics.

The invention discloses a water-spinning painting room. The water-spinning painting room comprises a painting room body arranged in a sealed manner. A static pressure box is arranged at the top of the painting room body and supplies air to the bottom of the painting room body from the top through an air supply system. A water-spinning treatment system is arranged below a surface grating plate at the bottom of the painting room body, and washing collection is carried out on paint mist generated in the painting operation process. The water-spinning treatment system communicates with an exhaust system. The water-spinning painting room is compact in structure, no pit needs to be dug, and construction is convenient and fast; a specific paint mist flocculating agent is added into circulating water, the paint mist is efficiently captured by highly mixing water and the paint mist in a water spinner, and paint residues are fished to be removed; the paint mist capturing efficiency is greatly improved, the work environment of workers is improved, and the physical and psychological health of operators is maintained; and the water-spinning painting room can be widely applied to governing of the paint mist generated in the coating operation, especially coating of small and medium workpieces.

The invention relates to a wide spectrum metal dielectric diaphragm grating for a femtosecond chirp-pulse amplification system, which comprises a substrate, a metal Ag film, a dielectric reflective film, a residual film layer and a surface grating structure; the dielectric reflective film comprises a HfO2 medium and a SiO2 medium which are deposited alternatively; the metal Ag film and the dielectric reflective film form a high reflective film; and the residual film layer is arranged between the surface grating structure and the dielectric reflective film. When the cycle of the grating is 550nm, the etching depth is 240nm, the thickness of the residual film layer is 10nm, the duty cycle is 0.26 and an incident angle is 53 degrees, to TE (Transverse Electromagnetic) wave with the central wavelength being 800nm, the -1 grade diffraction efficiency of the wide spectrum metal dielectric diaphragm grating for the femtosecond chirp-pulse amplification system from 744 nm to 874 nm is higher than 97 percent, and the effective working band width is up to 130nm. The wide spectrum metal dielectric diaphragm grating has important application value for improving the performance of the chirp-pulse amplification system.

The invention discloses a high-order surface grating surface-emitting semiconductor laser. The laser comprises a surface metal electrode layer, a ridge waveguide layer, a p-type doped cladding layer, a grating layer, a p-type doped optical confinement layer, a quantum well or quantum dot active area, an n-type doped optical confinement layer and a substrate layer, which are sequentially arranged, wherein a first-order grating is distributed on the grating layer; a high-order surface grating for coupling optical energy resonating along the horizontal direction to the perpendicular direction for output is distributed above the first-order grating in the center of a resonant cavity. The length of the high-order surface grating positioned above the grating layer in the center of the resonant cavity of the laser is (9 to 100) microns. A traveling wave mode in the resonant cavity of the laser is coupled into a radiation mode to realize surface output of laser by the high-order surface grating. The surface output light of the laser is directly coupled with a fiber core of a standard single-mode optical fiber. A segment of central phase shift is introduced into the center of the high-order surface grating, so that the coupling efficiency of the high-order surface grating surface-emitting laser and the standard single-mode optical fiber can exceed 50 percent.

The invention discloses a method for improving terahertz wave generation efficiency and transmissivity. The method comprises the following steps: obtaining an angle of inclination; obtaining a function expression of the amount of inclination according to the angle of inclination and a grating dispersion equation; obtaining the front surface grating ruling density of lithium niobate crystals according to the Littrow incidence condition, a grating equation and the function expression of the amount of inclination; modeling the grating by a modal method to obtain the grooving width and depth according to the relations between the minus one order diffraction efficiency of the grating and the filling factor and grooving depth of the grating; carving grating structures on the planes of incidence of the lithium niobate crystals by a micro-nano machining method in the machining tolerance range according to the front surface grating ruling density and the grooving width and depth; adding micro right-angle pyramid structures on the incidence interfaces of the lithium niobate crystals through micro-nano machining; and ensuring a pumped laser to emit pump light at specific incidence angles on the front surfaces of the lithium niobate crystals and generate terahertz waves on the emergence interfaces, wherein the grating ruling is parallel to the light axes of the lithium niobate crystals. The method has the beneficial effects of simplifying the components and shortening the light paths.

The invention provides a processing device and method of a curved-surface grating. A PDMS soft template is made, and arranged in an impression cavity, the air pressure of cavities on and under the PDMS soft template is controlled accurately, the PDMS soft template is impressed into the curved-surface grating by using a pressure difference between the upper and lower cavities, and technical parameters including the pressure difference between the upper and lower cavities, the template substrate distance and the substrate inclination angle are regulated to realize high-efficiency accurate manufacturing of the curved-surface grating.

Recent invention of longitudinally chirped volume Bragg gratings has dramatically changed a design of high power femtosecond lasers. Replacing of bulky pairs of conventional surface gratings with compact and robust chirped volume Bragg gratings for stretching and compression of laser pulses in chirped-pulse-amplification systems enabled decrease of size and weight of those systems by several times. The methods and devices enable substantial increase of stretching time and compression to shorter pulses, enhancement of stretched and compressed beams quality by stationary or dynamic shaping of gratings, and shaping of laser pulses in both temporal and spectral domains.

The invention relates to an optical splitting system of a flattening convex surface grating, comprising a light source, a light condenser, an incident narrow slot, a large-concave-surface reflecting mirror, a convex-surface grating and a surface array detector, wherein the sphere centers of the convex-surface grating and the large-concave-surface reflecting mirror are arranged on a same point, optical shafts are superposed, the incident narrow slot is arranged at a public sphere center of the convex-surface grating and the large-concave-surface reflecting mirror and is vertically arranged in a plane of a public optical shaft, the direction of the incident narrow slot is parallel to a notching direction of a grating, the surface array detector is arranged at the public sphere center of the convex-surface grating and the large-concave-surface reflecting mirror and is vertically arranged in the plane of the public optical shaft, the surface array detector and the incident narrow slot are arranged on two sides of the optical shaft, and white lights emitted by the light source are radiated to the large-concave-surface reflecting mirror through a focus lens and the incident narrow slot, is reflected and radiated to the convex-surface grating through the large-concave-surface reflecting mirror, is radiated onto the large-concave-surface reflecting mirror after passing through a diffracted wave diffracted by the convex-surface grating, and is finally converged to the surface array detector through the large-concave-surface reflecting mirror. The optical splitting system disclosed by the invention has the advantages of high spectrum resolution, approximative zero of spectral image distortion, simple structure, convenience in installation and low manufacturing cost.

The invention relates to a thin film type optical collimator on the basis of surface plasmon polaritons, which is formed by a substrate and a metal grating. The substrate is a glass substrate for bearing the metal grating; and the metal grating is formed by a metal medium alternate film and a metal surface grating structure, wherein the metal medium alternate film is obtained by alternately making a metal thin film and a medium thin film on the substrate by a vacuum hot dip coating technology or a magnetron sputtering technology and the metal surface grating structure is made on the metal medium alternate film by a two-beam interference exposure technology and a stripping technology. The structure changes Gaussian light into planar light by utilizing the metal medium alternate film for the first time and also has capacity of expanding the light beam width; the structure is compact, the size is small and the total thickness of a device is used as a wavelength magnitude; on the basis that the metal medium alternate film which adopts a simple preparation process and is low in cost supports the metal surface grating and conducts light, a metal film with a through hole, which is high in manufacturing cost, is avoided; and the thin film type optical collimator can be integrally made on the end faces of a semiconductor laser, a light emitting diode, an optical fiber or an optical fiber laser, and is used for improving an angle of divergence of a light beam and obtaining collimated light.

A semiconductor device contains a photodiode formed in a substrate of the semiconductor device. At a top surface of the substrate, over the photodiode, a surface grating of periodic field oxide in a periodic configuration and/or gate structures in a periodic configuration is formed. The field oxide may be formed using an STI process or a LOCOS process. A semiconductor device with a surface grating including both field oxide and gate structures has the gate structures over the semiconductor substrate, between the field oxide. The surface grating has a pitch length up to 3 microns. The surface grating covers at least half of the photodiode.

The invention discloses a metasurface micro-nano structure monolithic full-color waveguide lens and an AR display device. The metasurface micro-nano structure full-color waveguide lens comprises a waveguide substrate, a coupling-in grating and a coupling-out grating. The coupling-in grating and the coupling-out grating are a plurality of one-dimensional rectangular micro-nano structure metasurface gratings, are located on the surface of the waveguide substrate and are distributed at the two ends of the waveguide substrate; in each period, the coupling-in grating and the coupling-out grating are respectively provided with a plurality of sub-wavelength width rectangular micro-nano metasurface structures. Compared with a conventional grating, the metasurface grating has the resonance effect of different wavelengths, and can have high and balanced first-level transmission diffraction efficiency on red light, green light and blue light at a large incident angle. The lens is large in field angle and high in visual experience, full-color display can be achieved only through a single waveguide lens, and the AR display device adopting the waveguide lens is light in weight and good in wearable performance. Compared with a common grating, the plurality of rectangular micro-nano structure metasurface gratings are more in design variables, flexible in design and easier to process.

The invention discloses a system for quickly monitoring two-dimensional distribution of airborne atmospheric trace gases, which comprises an imaging spectrometer; the imaging spectrometer is externally connected with a control unit; an optical receiving system and a CCD (Charge Coupled Device) detector are arranged in the imaging spectrometer; the optical receiving system comprises an ultraviolet lens arranged on an imaging spectrometer housing; a plane reflection mirror facing to the ultraviolet lens is arranged in the housing; a concave surface reflection mirror is arranged in a light path in front of the plane reflection mirror; a convex surface grating is arranged on the reflection surface of the concave surface reflection mirror; incident light passes through the concave surface reflection mirror and the convex surface grating in sequence after being emitted by the ultraviolet lens; emergent light is received by the CCD detector; and the incident light and the emergent light are located at the same side of the convex surface grating. According to the invention, high spectral resolution and spatial resolution can be realized at the same time by the imaging spectrometer based on the convex surface grating capable of enabling the incident light and the emergent light to be located at the same side of the convex surface grating.