72 results about "Diffraction effect" patented technology

The invention belongs to the technical field of metal crack detection, and discloses a metal microcrack ultrasonic detection method, which comprises the following modules: an ultrahigh frequency composite array probe with a center frequency dynamic adjustable range of 5-50 MHz; the dual-mode excitation and receiving module is used for independently generating a pulse reflection mode excitation signal and a diffraction mode chirp frequency modulation signal; the phase-controlled synthetic aperture dynamic focusing module is used for realizing + / -60-degree deflection and sub-wavelength level focusing of acoustic beams; the nonlinear harmonic enhancement module is used for exciting a crack nonlinear effect by superposing 1-2MHz fundamental waves; and a time-space-frequency three-domain data fusion module. According to the method, signal-to-noise ratio collapse caused by the diffraction effect in a traditional method is overcome, more importantly, the system has low-frequency penetrability and high-frequency resolution at the same time due to 80%-120% of broadband coverage of chirp frequency modulation signals, the diffraction signal gain is increased by 20 dB or above, a near-surface blind area is compressed to be within 0.2 mm, and the system can be applied to the field of radar imaging. And the core pain point of missing detection of the near-surface microcracks of the thin-wall component is solved.

The invention provides a deep tunnel micro-seismic source positioning method and system, and relates to the technical field of micro-seismic source positioning, and the method comprises the steps: obtaining first information, second information and third information; performing particle swarm initialization according to the first information, the second information and the third information to obtain an initial particle swarm parameter set; performing diffraction path judgment according to the particle swarm parameter set to obtain a judgment result of a diffraction occurrence condition; calculating a minimum diffraction path according to a diffraction identification result to obtain a shortest path length set; according to the shortest path length set and the second information, carrying out wave velocity inversion to obtain an optimal wave velocity value and a seismic source spatial position; and according to the optimal wave velocity value and the seismic source spatial position, carrying out seismic moment calculation to obtain seismic moment data. According to the method, accurate modeling and path compensation of an elastic wave diffraction effect are realized, so that propagation path deviation caused by existence of a goaf is effectively eliminated, and the accuracy and reliability of deep tunnel micro-seismic source positioning are remarkably improved.

An optical waveguide device and a preparation method therefor, and a near-eye display device. The optical waveguide device (1) comprises at least one optical waveguide (10). The optical waveguide (10) comprises: a waveguide sheet (11), which is used for making light beams transmit in the waveguide sheet (11) in a total reflection manner, wherein the waveguide sheet (11) has a coupling-in region (B) and at least two coupling-out regions (A); a coupling-in grating (12), which is arranged in the coupling-in region (B) and is used for coupling the light beams into the waveguide sheet (11); and at least two coupling-out gratings (13), which are correspondingly arranged in the at least two coupling-out regions (A) on a one-to-one basis, and are used for coupling out the light beams, which are transmitted in the waveguide sheet (11) in a total reflection manner, wherein the light intensities of the light beams coupled out by the at least two coupling-out gratings (13) are identical. The present application can improve the exit pupil uniformity of the optical waveguide device (1), thereby improving the visual experience of users, and also reducing the research and development costs incurred by the use of masks and the impact caused by diffraction effects.

To provide a technique capable of reducing the influence of the variation in the thickness of a resin cured material layer having projecting parts for developing diffraction action on the light utilization efficiency of a diffraction optical element.SOLUTION: The diffractive optical element 10 is used for at least one of division and shaping of a laser beam having a wavelength in a near-infrared region, and includes a substrate 11 that transmits the laser beam, and a cured resin layer 12 that is provided on the substrate 11 and transmits the laser beam, the cured resin layer 12 having a refractive index of 1.6 or less at a wavelength of 9400 nm, and generating a plurality of convex portions 12P that exhibit a diffractive action on a surface of the diffractive optical element 10, each of the plurality of convex portions 12P having a height H in a range of 1.4 μm or more and 1.7 μm or less, the width W is in a range of 0.4 μm or more and 1.0 μm or less.SELECTED DRAWING: Figure 1

The invention discloses a photonic crystal surface emitting laser based on electro-optical effect modulation and an emission angle and wavelength regulation and control method thereof, and belongs to the field of laser devices. The photonic crystal surface emitting laser comprises a substrate layer, an isolation layer and an active LiNbO3 layer; the isolation layer is a SiO2 isolation layer or an air isolation layer, and the air isolation layer is formed by etching the SiO2 isolation layer through a SiO2 etching agent; the active LiNbO3 layer is made of erbium-doped LiNbO3 or ytterbium-doped LiNbO3, and periodic holes are etched in the surface of the active LiNbO3 layer to form the photonic crystal layer. The photonic crystal surface emitting laser is prepared by using the active electro-optical effect material, the electro-optical effect material is combined with the photonic crystal surface emitting laser, and the emission angle and the emission wavelength are regulated and controlled through the electro-optical effect of LiNbO3 and the diffraction effect of the photonic crystal.

The application discloses a long-wave infrared dynamic space modulation device and method based on double coding apertures, and belongs to the technical field of optics. The application avoids the diffraction effect in the long-wave infrared space modulation process by selecting a large-size coding pixel coding aperture, adopts a double coding aperture space light modulation structure, separately performs space modulation on target light beams, and realizes coding effect superposition through beam combination, so that the space modulation resolution of the large-size coding pixel coding aperture is improved. On the premise of guaranteeing the space modulation resolution requirement and without increasing the coding aperture area, the diffraction effect in the long-wave infrared space modulation process is avoided by selecting the large-size coding pixel coding aperture. The application introduces the use of a displacement table, and the position of the moving coding template is transformed for multiple times within the single information acquisition time of the system, so that the effective coding area in the optical path is transformed, more coding superposition effects are generated, and the coding resolution and the coding gray scale are further improved.

This invention claims protection for a laser device and optical path debugging method for acquiring micro-sized beams, belonging to the field of solid-state laser technology. The device structure includes: an indicator light source, a high-gain module, a micro-sized pinhole aperture, a micro-sized output mirror, and a micro-sized reflector. The debugging method consists of the following steps: S1: Determine the pitch and yaw of the micro-sized reflector using the indicator light source and the micro-sized pinhole aperture; S2: Determine the spontaneous emission light path of the high-gain module based on the micro-sized reflector and the two micro-sized pinhole apertures; S3: Add the micro-sized output mirror to achieve laser resonator oscillation based on the micro-sized cavity mirror. Because the cavity mirror is small enough, this invention eliminates the need for external pinhole beam contraction, reducing diffraction effects. Furthermore, by using an internal pinhole aperture to determine the optical path, it solves the problem of the spontaneous emission amplification optical path of the module not coinciding with the resonator oscillation optical path, improving output power and meeting the requirements for outputting micro-sized beams based on a high-gain module.

According to the laser generating device and the laser system, the image transmission device is introduced, the object image surface of the image transmission device is accurately overlapped with the two cavity reflectors of the resonant cavity, the important beneficial effects are achieved, the effective transmission distance of light waves between the two cavity reflectors is equivalently eliminated optically, and the laser generating device and the laser system have the advantages of being simple in structure and convenient to use. Therefore, the inherent diffraction effect and the mode selection capability of the resonant cavity are thoroughly inhibited; the direct result is that a large number of laser transverse modes with different orders are allowed to simultaneously meet oscillation conditions and start oscillation in a cavity, and light fields of the multiple transverse modes are combined into a large-mode-field output light beam with the spot size equivalent to the aperture of a gain medium after incoherent superposition. Moreover, the near-field energy distribution is converted from the conventional Gaussian distribution to super Gaussian distribution with a flat top and a steep edge.

The present disclosure relates to electronic devices having a display panel and a plurality of optoelectronic components, and in particular to mechanisms for mitigating diffraction effects when light is exchanged by such optoelectronic components through at least one transmissive region of the display panel. The display panel may be one of and include a layered semiconductor device that, in some non-limiting examples, may be an optoelectronic device having a plurality of (sub) pixel emission regions, each (sub) pixel emission region including a first electrode and a second electrode separated by at least one semiconductive layer.

The invention provides a method for realizing ultra-high-speed translation of a Bessel beam by using double acousto-optic modulation elements, which is characterized in that the displacement in the x-axis direction and the displacement in the y-axis direction are changed at a high speed by quickly switching radio frequencies f1 and f2, so that ultra-high-speed punching on the surface of a workpiece is realized; meanwhile, each hole has excellent morphology consistency due to vertical incidence, so that the problem of hole shape distortion caused by inclined incidence at the scanning edge of a traditional galvanometer is avoided; that is to say, the all-solid-state diffractive optical element is adopted, no mechanical moving part exists, the limitation of mechanical inertia is completely eliminated, the response time of light beam displacement only depends on the change speed of a driving signal and the establishment time of the diffraction effect, the MHz-level control effect can be easily achieved, and the speed is several orders of magnitude faster than that of a traditional galvanometer. The method is especially suitable for application scenes such as laser processing, optical tweezers, confocal microscopic imaging and high-speed optical switches.

A variable light transmission device is disclosed that mitigates negative aperture diffraction effects and shows good switching speed between the open and the closed optical states. The device comprises a microcell layer disposed between two light transmissive electrode layers, the microcell layer having a plurality of microcells, each microcell including an electrophoretic medium. And each microcell comprises a protrusion structure and a channel.

The application discloses a kind of optical fiber side light extraction structure and method, belong to optical fiber side light extraction technical field, structure has including femtosecond grating light extraction component, filter component including filter layer and with slit light shielding layer, and detection component.The method includes: with grating diffraction separation optical signal in fiber core, with filter component filters optical signal, with detector receives signal.The application is by femtosecond laser in fiber core and writes small refractive index modulation area, with diffraction effect will transport light be introduced with specific angle to side, again cooperate external filter and metal slit and constitute spatial filter, physically block the stray light deviating from preset angle.This internal diffraction+external filter synergic mechanism avoids physical damage optical fiber surface, and realizes high purity, high directional signal extraction under micro size.

A variable light transmission device is disclosed that mitigates negative aperture diffraction effects and shows good switching speed between the open and the closed optical states. The device comprises a microcell layer disposed between two light transmissive electrode layers, the microcell layer having a plurality of microcells, each microcell including an electrophoretic medium, and each microcell comprising a channel, a protrusion structure, the protrusion structure having one or more concavities.

To solve the numerous sound quality challenges encountered when using MEMS microphones utilizing microelectromechanical systems (hereinafter referred to as MEMS) based on semiconductor manufacturing technology widely used in smartphones and other devices, which are compact and possess the advantages of being durable and highly reliable due to the use of semiconductor manufacturing technology, as high-fidelity recording microphones, due to their size and structure.SOLUTION: By using a plurality of MEMS microphones in parallel, suppressing the steep peaks in the high-frequency range inherent to MEMS microphones, minimizing the effects of phase differences caused by a plurality of units, driving the frequency response compensation circuit with low power, and preventing degradation in sound quality due to diffraction effects, a microphone for high-quality audio capture is realized.SELECTED DRAWING: Figure 1

The application is a device for testing parallelism of two gratings, which comprises a first grating, a second grating, a laser, a pinhole diaphragm, a half-transmission half-reflection prism, a pentagonal prism and an observation screen arranged on the same optical axis, and comprises two parts of adjusting grating surface parallelism and adjusting grating line parallelism. Two light spots on the observation screen are in the same horizontal straight line by adjusting the deflection angle of the first grating and the second grating through mirror reflection of the first grating and the second grating, so that the grating surface parallelism of the two gratings is adjusted. Two light spots on the observation screen are in the same vertical straight line by adjusting the rotation angle of the first grating and the second grating rotating around the horizontal direction through the diffraction effect of the first grating and the second grating, so that the grating line parallelism of the two gratings is adjusted. The application has simple structure, easy-to-understand principle and convenient operation.

A variable light transmission device is disclosed that mitigates negative aperture diffraction effects and shows good switching speed between the open and the closed optical states. The device comprises a microcell layer disposed between two light transmissive electrode layers, the microcell layer having a plurality of microcells, each microcell including an electrophoretic medium, and each microcell comprising a channel, a protrusion structure, the protrusion structure comprising a conoid geometric solid.

A variable light transmission device is disclosed that mitigates negative aperture diffraction effects and shows good switching speed between the open and the closed optical states. The device comprises a microcell layer disposed between two light transmissive electrode layers, the microcell layer having a plurality of microcells, each microcell including an electrophoretic medium, each microcell comprising a protrusion structure, the protrusion structure having one or more wells.

The present application belongs to the technical field of anti-fake gilding, and discloses a multilayer structure anti-fake gilding method, which comprises the following steps: step 1, manufacturing a micro-nano gilding plate with microstructure; step 2, manufacturing a transparent color-changing gilding film; step 3, printing a pattern on the surface of a substrate; and step 4, using the micro-nano gilding plate with microstructure manufactured in step 1 to stamp the transparent color-changing gilding film manufactured in step 2 on a four-color image. The gilding plate with optical microstructure is adopted in the present application to produce diffraction effects on the surface, such as light column, frosted glass, embossing and other effects. The gilding film adopts high-transparency pearl luster, and has very strong diffraction color-changing effect. The multilayer color-changing effect is achieved through the multiple superposition of light diffraction and interference to achieve the anti-fake effect. The combination and location of the printed image can meet the high aesthetic requirements, and the anti-fake pattern produced has diversity.

A holographic security code comprising: a pattern of elementary cells having a predetermined shape and a predetermined relative position, said pattern comprising a two-dimensional sequence of said elementary cells; said pattern comprising a predetermined number of so-called "empty" elementary cells, i.e. such as to appear in a predetermined dark color, in particular black, and said pattern comprising a predetermined number of elementary cells that generate a diffractive effect, so-called iridescent cells, and which each comprise at least one diffractive grating having a predetermined orientation, preferably a combination of at least two diffractive gratings that differ between their orientation; said diffractive gratings being made in such a way that the light radiation emitted is visible only with an observation according to different viewing angles comprised in a predetermined range, said pattern generating, when observed according to the aforementioned viewing angles, an image consisting of the combination of said predetermined number of so-called empty cells, having a predetermined dark colour, preferably black, and of so-called iridescent cells and in particular of different colours contrasting with said dark colour of the so-called empty cells; while with viewing angles and / or illumination outside said range of viewing angles, in particular perpendicular to the surface along which said two-dimensional sequence of elementary cells extends, said empty elementary cells and said iridescent elementary cells do not have a different appearance from each other; said elementary cells having sides lengths and / or diagonals or larger diameters in the range from 50 to 300 microns. The invention also concerns a holographic security product characterized by the fact that it comprises a substrate on which said aforementioned holographic code is applied. In addition, the invention has as its object an anti-counterfeiting verification system, said system comprising: a plurality of anti-counterfeiting labels that comprise a product of the aforementioned type; at least one code reader applied to said labels, said codes being made up of at least one said holographic code; at least one processing unit comprising a memory wherein the aforementioned codes are stored and at least one program for comparing the codes transmitted by the reader and the codes contained in said database, at least one visual and / or acoustic reception and reproduction unit associated with said reader; said processing unit generating a confirmation or denial signal of the authenticity of the code depending on the outcome of said comparison, said signal being transmitted to said visual and / or acoustic reproduction unit for the emission of visual and / or acoustic information about the confirmation or denial of authenticity of said code.

The invention provides a mask structure parameter optimization method and device and a computer readable storage medium. According to the optimization method of the mask structure parameters, first diffraction field distribution associated with to-be-optimized first mask structure parameters is constructed based on a propagation path after incident light encounters a mask, and according to an imaging model of an imaging system, imaging intensity distribution of the first diffraction field distribution after the first diffraction field distribution passes through the imaging system is constructed; according to the correlation information between the intensity distribution and the imaging quality parameter, the first mask structure parameter is optimized by taking the imaging quality parameter reaching the first preset condition as an optimization target, and the optimized first mask structure parameter is obtained, so that the imaging quality parameter of the mask structure is close to the first preset condition; the imaging quality parameter of the mask structure is improved, and the influence of the diffraction effect of the mask structure on the incident light on the imaging quality is reduced.

The present disclosure relates to electronic devices having a display panel and a plurality of opto-electronic components, and in particular, mechanisms for mitigating diffraction effects when exchanging light, by such opto-electronic components, through at least one transmissive region of the display panel. The display panel may be one of: be, and comprise, a layered semiconductor device, which in some non-limiting examples, may be an opto-electronic device, having a plurality of (sub-) pixel emissive regions, each comprising first and second electrodes separated by at least one semiconducting layer.

The embodiment of the application provides a wavelength selective switch, which comprises a dispersion element and a switching engine. The dispersion element can disperse multiplexed light input from an input port into a plurality of sub-beams in a dispersion plane and irradiate the sub-beams to the switching engine. The switching engine can deflect the plurality of sub-beams to form deflected sub-beams according to preset deflection angles in a switching plane, and output the deflected sub-beams from corresponding output ports. The deflection angles of one kind of wavelength beam and other wavelength beams are different, so that the one kind of wavelength beam can be separated and output from different output ports, and the scheduling and distribution of signal wavelengths are realized. The wavelength selective switch further comprises a first lens group. The first lens group can irradiate the multiplexed light to the dispersion element along a direction parallel to the dispersion plane in the switching plane, and irradiate the sub-beams dispersed by the dispersion element to the switching engine. The oblique incidence angle between the multiplexed light and the dispersion element is eliminated, the conical diffraction effect of the dispersion element is reduced, and the filter passband performance of the wavelength selective switch is improved.

Several aspects of the revelation concern an optical arrangement (100) comprising several holographic optical elements, HOE, (91, 92). At least one HOE disperses the light. For example, a deflecting HOE (91) directs light onto a diffuser HOE (92), where the light is dispersed by diffraction effects. By such a staggered arrangement of the two holographic optical elements (91, 92), the optical arrangement can, for example, be made particularly compact. Stray light can be reduced.

Disclosed herein is a non-destructive method for determining a vertical extent of a feature of a patterned wafer, the method including using a scanning electron microscope (SEM) to scan an e-beam over a featured region on a tested wafer and sense backscattered electrons returned from the tested wafer to obtain a backscattered electron (BSE) image of the featured region, wherein the scanned e-beam is projected on the tested wafer so as to impinge thereon at an electronic tilt angle of up to 2° in order to minimize non-linear diffraction effects.

The invention discloses a method for determining the optimal size of a collimated light beam in a high-energy laser system. The method comprises the following steps: S1, acquiring basic parameters of the high-energy laser system; s2, establishing an electric field distribution model of the Gaussian beam on a diaphragm plane; s3, establishing an electric field distribution model after the Gaussian beam passes through the diaphragm; s4, establishing an electric field distribution model after the light beam is transmitted for a specified distance through the diaphragm; s5, establishing a light intensity distribution model after the Gaussian beam is transmitted for a specified distance through the diaphragm; s6, transmitting antenna parameters are converted into equivalent focusing parameters, and a focal plane electric field and focal spot light intensity distribution model of the Gaussian beam is established; and S7, selecting the waist radius of the input light spot. According to the invention, the efficiency waste caused by overlarge lens allowance and insufficient utilization of effective aperture in the prior art is avoided, and the problem that the energy distribution of light beams is influenced by diffraction effect caused by light cutting is solved.

This invention provides a method and system for locating microseismic sources in deeply buried tunnels, relating to the field of microseismic source location technology. The method includes: acquiring first, second, and third information; initializing a particle swarm based on the first, second, and third information to obtain an initial particle swarm parameter set; identifying diffraction paths based on the particle swarm parameter set to obtain a determination result of diffraction occurrence conditions; calculating the minimum diffraction path based on the diffraction identification result to obtain a set of shortest path lengths; performing wave velocity inversion based on the set of shortest path lengths and the second information to obtain the optimal wave velocity value and the spatial location of the seismic source; and calculating the seismic origin time based on the optimal wave velocity value and the spatial location of the seismic source to obtain seismic origin time data. This invention achieves accurate modeling and path compensation for elastic wave diffraction effects, thereby effectively eliminating propagation path deviations caused by the existence of voids and significantly improving the accuracy and reliability of microseismic source location in deeply buried tunnels.

A variable light transmission device is disclosed that mitigates negative aperture diffraction effects and shows good switching speed between the open and the closed optical states. The device comprises a microcell layer disposed between two light transmissive electrode layers, the microcell layer having a plurality of microcells, each microcell including an electrophoretic medium, and each microcell comprising a channel, a protrusion structure, the protrusion structure having one or more concavities.

The application discloses a liquid surface under sonar detection target, which is used for liquid surface under detection of a sonar device. The detection target comprises a target head, a support and a sound shadow tracking mechanism. When the detection target and the sonar device are simultaneously located on a liquid surface, the support is located in a sound shadow area range caused by the sonar wave emitted by the sonar device acting on the target head. When the detection target and the sonar device are simultaneously submerged under the liquid surface and the detection target is deformed, the support is kept in the sound shadow area range caused by the sonar wave emitted by the sonar device acting on the target head by the action of the sound shadow tracking mechanism. The sound shadow area formed by the detection target in the sonar wave range of the sonar device is utilized, the deformation of the support caused by the action force is reduced by the sound shadow tracking mechanism, the influence of the deformation on the test result is reduced, the support can be completely hidden in the sound shadow area, the reflection effect and the diffraction effect of the support are avoided, and the influence on the performance test result of the active sonar is greatly reduced.

An apparatus includes an optical system, a transmitter, and a detector. The optical system includes a transmitter-side component and a detector-side component. The transmitter is adapted to transmit a first plurality of light spots along a transmitter-side optical path passing through at least one transmission region of the transmitter-side component and outside the apparatus. The detector is adapted to detect a second plurality of light spots from outside the apparatus and along a detector-side optical path passing through at least one transmission region of the detector-side component. The transmitter-side component is adapted to apply a first diffraction effect to the first plurality of spots, the first diffraction effect introducing at least one n-order diffraction point, each n-order diffraction point corresponding to one of the first plurality of spots. The detector-side component is adapted to apply a second diffraction effect to the second plurality of spots prior to detection by the detector.