148 results about "Light field imaging" patented technology

A multispectral light field imaging system includes a primary lens, a microlens array, a first relay lens, a dichroic lens, a second relay lens, a third relay lens, a first image sensor, a first filter, a second image sensor and a second filter, wherein the microlens array is located at an image plane of the primary lens; the first relay lens together with the second relay lens and the third relay lens forms a 1:1 relay lens group imaging system on a spectral band 1 light path and a spectral band 2 light path respectively; the dichroic lens forms an included angle of 45° with a light axis; the first image sensor is located at a focal plane of the second relay lens, and the second image sensor is located at a focal plane of the third relay lens.

A method and system for 3D contour reconstruction of AM parts based on light field imaging, belonging to the field of image reconstruction technology is provided. The method includes constructing an EPI-UNet framework, where a preset light field dataset is used to construct a training set, learning labels from the disparity maps corresponding to the preset light field dataset are obtained, and EPI-UNet framework is trained to obtain a predicted disparity vector with the training set and learning labels. Two mappings including disparity and depth mapping, and disparity and 3D mapping, are established to get 3D contour of the AM part. The experiments of validation for accuracy and 3D contour reconstruction of AM parts were performed. By applying light field multi-view vision to the AM process and combining the rich angle and spatial domain view information of the light field, this disclosure provides a reliable quality assurance for AM monitoring.

The invention provides a molten pool temperature field in-situ monitoring method and system based on multi-view light field imaging, and the method employs a light field camera multi-view system, obtains molten pool images of R, G and B channels through building a light field sub-aperture Bayer model, and calibrates the relative spectral responsivity of a light field camera and the proportion of dual-wavelength intensity under a coaxial temperature measurement system. Molten pool images of two channels are selected from the molten pool images of the R channel, the G channel and the B channel, calibration parameters are combined, and a molten pool temperature field is derived through a dual-wavelength temperature measurement method. A blackbody furnace is adopted to calibrate a multi-view light field temperature measurement system, and the error of a monitored temperature field is kept below 3%. The method simplifies the monitoring process, improves the temperature measurement precision, has a wide temperature range and low complexity, can perform in-situ monitoring on the high-temperature metal molten pool, and has a wide application prospect in the field of additive manufacturing.

Disclosed in the present invention are a multispectral light field imaging system, and a three-dimensional temperature field measurement method and measurement system. The multispectral light field imaging system comprises: a primary lens, a micro-lens array, a first relay lens, a dichroic mirror, a second relay lens, a third relay lens, a first image sensor, a first optical filter, a second image sensor and a second optical filter, wherein the micro-lens array is located at an image plane of the primary lens; the first relay lens, the second relay lens and the third relay lens together form a 1:1 relay lens group imaging system on an optical path of a spectral band I and an optical path of a spectral band II; an angle of 45° is formed between the dichroic mirror and an optical axis; and the first image sensor is located at a focal plane of the second relay lens, and the second image sensor is located at a focal plane of the third relay lens. The present invention realizes the collection of multispectral light field data while maintaining the amount of light field data of each spectrum unchanged, such that an instantaneous three-dimensional temperature field of a flow field can be measured.

The invention relates to the field of light field imaging, in particular to a light field camera calibration method based on original light field image line feature detection, which comprises the following steps: acquiring a white background original light field image set of a light field camera under different shooting conditions, and processing to obtain projection center grid data of a microlens array; obtaining a checkerboard original light field image set of the light field camera under different shooting conditions, and loading projection center grid data of the micro-lens array on each checkerboard original light field image; calculating a gradient value of each pixel in each checkerboard original light field image, queuing the gradient values of the pixels, and performing region diffusion and model fitting according to a gradient angle similar direction to obtain line features in each checkerboard original light field image so as to calculate angular point coordinates of each checkerboard original light field image; and constructing a light field camera projection model, and calibrating parameters of the light field camera in combination with the angular point coordinates. According to the method, introduced errors are reduced while time is saved.

The invention provides a single-layer large-view-field broadband achromatic metamaterial lens and a design method thereof. The super-structure lens comprises a unit structure array and a substrate from top to bottom, and the shape of a unit structure is related to the polarization characteristic of the super-structure lens. A large-view-field broadband super-structure lens design is realized by using a principle of combining a secondary phase with achromatism, a phase-wavelength-incident angle database and an amplitude-wavelength-incident angle database of a scanning unit structure are obtained by changing the geometric size and the incident angle of the unit structure, the unit structure with large angle tolerance is screened out by using an optimization algorithm, and a super-structure with a wide angle tolerance is obtained. Therefore, the super-structure lens has the performance of a large view field, the actual phase provided by the unit structure in the database can be matched with the target phase, and the broadband achromatic performance is achieved. The device is ingenious in design and simple in structure, the large-view-field broadband achromatic focusing function can be achieved through the single-layer super-structure lens, and the device can be used in functional devices for polarization detection, light field imaging, wavefront detection and the like.

The invention discloses a three-dimensional combustion multi-parameter field inversion method based on two-dimensional infrared imaging and hyperspectral light field imaging, and belongs to the technical field of flame combustion detection. The invention aims to solve the problem of low reconstruction precision caused by limited spontaneous radiation information and poor low-temperature region signal sensitivity in the existing combustion flow field temperature field reconstruction. Comprising the following steps: obtaining a flame two-dimensional infrared temperature distribution image and a flame hyperspectral light field image; a two-dimensional blackbody radiation intensity curve and a three-dimensional blackbody radiation intensity curve are obtained through calibration according to the blackbody radiation law; combining the corresponding image gray values to obtain two-dimensional infrared radiation intensity, three-dimensional visible radiation intensity and three-dimensional infrared radiation intensity; determining a temperature threshold value of the high-temperature area; constructing a multispectral radiation source term matrix equation, and reconstructing a three-dimensional temperature field; obtaining a separated flame hyperspectral light field image, and reconstructing a low-temperature region and a reconstructed temperature field; and combining with a high-temperature region reconstruction temperature field to obtain a whole temperature field. The method is used for three-dimensional combustion multi-parameter field inversion.

The invention relates to the technical field of laser precision machining, and discloses a laser precision machining device and method for dynamically adjusting beam shaping based on light field imaging, and the device comprises a laser emission unit, an X-axis movable laser reflector, an X-axis and Y-axis movable laser reflector, a dynamic shaping module and a focusing galvanometer system. The laser emitting unit, the X-axis movable laser reflecting mirror, the X-axis and Y-axis movable laser reflecting mirror, the dynamic shaping module and the focusing galvanometer system are all fixed to a support at the top of the supporting table. According to the invention, based on a specially designed laser, laser beam phase space distribution is adjusted by using a variable optical path to realize beam shaping, a laser beam can be changed into a rectangular flat-topped light spot, and the size of the rectangular light spot is adjusted through the size of the optical path. And the focal length of the laser beam and the size of the flat-topped light spot can be dynamically adjusted, and uniform machining on microelectronic device packaging, wafer surfaces and optical element surfaces is achieved.

The invention relates to the technical field of optical imaging, and discloses a light field imaging method and device, a medium, an imaging unit and an imaging system.The method comprises the steps that a first sub-aperture image collected by a first imaging unit at the current moment is obtained; generating first exchange information, transmitting the first exchange information to each second imaging unit, and acquiring second exchange information transmitted by each second imaging unit; the exchange information comprises a sub-aperture image and a reconstructed light field; performing environment light field reconstruction according to the first sub-aperture image, each second sub-aperture image and each second reconstruction light field at the previous moment, and generating a first reconstruction light field at the current moment; and under the condition that the preset imaging target is not completed, performing environment light field reconstruction again at the next moment until the imaging target is completed. According to the method, a centralized light field data processing mode is not needed, the requirements for system computing power and data bandwidth are reduced, and processing is more flexible.

The invention discloses a multi-frame reconstruction multispectral imaging system based on dynamic space-time joint coding. The system comprises a filtering window module used for limiting the spectral range of imaging; the spatial code modulation module is used for providing spectral codes in a spatial dimension; the time coding modulation module is used for carrying out inter-frame modulation on the spectrum codes provided by the space coding modulation module; the optical imaging module is used for imaging the light field modulated by the time coding modulation module on the color acquisition module; the color acquisition module is used for carrying out further spectral coding on the light field to obtain a measurement image; a calculation reconstruction module; the method is used for recovering a high-dimensional multispectral image data cube by using a measurement image. The method has the advantages of being light in weight, low in cost, high in underqualitative relieving capacity, efficient and stable in reconstruction method, high in adaptability and practicability and the like.

The invention relates to an improved cage type light field imaging system and a debugging method, and belongs to the technical field of light field imaging, and the system comprises a main lens which is used for collecting light spots on an object surface, and enabling the light emitted by the light spots to be imaged on a micro lens; the micro lens is used for separating the light collected by the main lens into light beams in different directions and imaging the light beams on a virtual image plane; the relay lens is used for carrying out secondary imaging on the light beams in different directions to different pixels of a CCD detector of the camera; the relay lens comprises a first lens and a second lens, the focal lengths of the first lens and the second lens are positive, the focal length of the first lens is smaller than that of the second lens, and the magnification of the relay lens is larger than 1: 1. In the debugging process of the system, parallel light beams are arranged in front of the micro lens, and the position of the micro lens is determined in the mode that the parallel light beams vertically enter the micro lens. The system is not influenced by vignetting and distortion generated by the relay lens any more, and the debugging method improves the positioning precision of the micro lens.

The invention discloses a near-infrared light field three-dimensional imaging system and application, and the system is based on single-photon imaging and comprises an illumination light path and a light field imaging light path. The illumination light path generates an illumination light beam of a near-infrared band, and the illumination light beam is projected on a sample by adopting vertical illumination to excite fluorescence of the sample in a Rayleigh range of the illumination light beam; a light spot in the Rayleigh range of the illumination light beam is elliptical; a galvanometer is arranged in the illumination light path, and a tube lens is arranged between the galvanometer and the objective lens, so that an illumination light beam scans in an imaging view field in parallel to a main optical axis of the objective lens; the light field imaging light path is provided with a microlens array, collects fluorescence emitted by the sample, records the fluorescence direction to obtain light field information, and performs light field three-dimensional imaging on the sample. According to the invention, selective illumination is realized by shaping the illumination beam of the near-infrared band, the imaging quality, the imaging depth and the imaging speed of light field three-dimensional imaging are considered in combination with beam scanning, and the method is suitable for real-time three-dimensional imaging of a living body.

The invention provides a light field detector based on a micro-nano optical structure and a light field imager. The light field detector comprises a substrate, an active region, an electrode and the micro-nano optical structure, wherein the micro-nano optical structure is prepared on the surface of the active region and / or the electrode; the micro-nano optical structure prepared in the active area is used for regulating and controlling the light field distribution of incident light in the active area, and the micro-nano optical structure prepared on the surface of the electrode is used for regulating and controlling the transmittance of the incident light, so that the light field detector generates different adjustable and controllable light responses to the incident light carrying different optical information under the driving of different voltages. Therefore, the adjustable reconstruction of the multi-dimensional optical information of the incident light can be realized. The optical information comprises wavelength information, optical power information, optical polarization information and optical phase information.

The invention provides a light field regulation and control method and device, and relates to the technical field of light field regulation and control. The light field regulation and control method comprises the following steps: dividing an input light beam into a first light component and a second light component under the condition that the input light beam is modulated into a first polarization direction; a light field modulation module modulates the first light component and the second light component to obtain a modulated first light component and a modulated second light component; combining the modulated first light component and the modulated second light component to obtain a combined light beam; modulating the combined light beam towards a second polarization direction to form a vector light field; imaging is carried out based on the vector light field, and the spatial intensity distribution and polarization characteristics of the vector light field are obtained under the condition that optimal light field imaging is obtained. According to the light field regulation and control method and device, light beam distortion can be compensated through the phase modulation capacity, and meanwhile the incident polarization state can be changed through the polarization modulation capacity.

The invention discloses a method for performing three-dimensional positioning by using a light field microscope, which belongs to the field of light field microscope imaging, and comprises the following steps of: S1, performing light field imaging of an object by using the light field microscope, calibrating an observed original light field image and decoding the original light field image into a biplane parameterized four-dimensional format, therefore, a real polar plane image, namely a real EPI, is formed; s2, wave light forward direction models of spherical volumes located at different depths are used for simulating a set of light fields, a depth perception dictionary is constructed, and each atom is a synthetic polar plane image related to the specific depth, namely a synthetic EPI; s3, implementing three-dimensional positioning by executing a convolutional sparse coding model based on a depth perception dictionary and a dry friction inertial near-end gradient algorithm (IPGDF) on the observed polar plane image; according to the invention, the positioning precision and the positioning speed of three-dimensional positioning under the light field microscope are improved.

The invention discloses a light field microscopic self-supervised denoising system and method fusing a physical process. The system comprises a light field imaging subsystem and a self-supervised denoising subsystem. The light field imaging subsystem is used for capturing multi-view light field original data of a sample; the self-supervised denoising subsystem is used for processing original data of a light field, preprocessing the original data of the light field in a training stage, and decomposing the original data into multi-view sub-images; the method comprises the following steps: constructing original data of a training set through two different self-supervision strategies, and then generating a self-supervision training data pair through RL deconvolution according to a physical optical process; and finally, a denoising model is obtained through 3D neural network training. In the reasoning stage, light field original data to be reconstructed are preprocessed and then subjected to RL deconvolution to generate input data to be denoised, the input data are input into the trained denoising model, and a reconstruction result is output. According to the invention, the problems of noise amplification, data dependence and poor universality of the light field fluorescence microscope are effectively overcome.

The invention discloses a transient three-dimensional combustion flow temperature field real-time measurement method based on combination of regularization Kalman filtering and a micro-lens array. The method comprises the following steps: firstly, setting radiation distribution at an initial moment, and setting an initial error covariance matrix of a measurement model and an estimation model; secondly, a micro-lens array light field imaging system is used for obtaining a light field image of a combustion flow field; constructing a matrix form and a radiation coefficient matrix of a radiation observation model of the combustion flow field according to the obtained light field image; then Kalman filtering estimation is carried out to obtain flow field radiation source distribution; and finally, according to the processed flow field radiation source distribution, reconstructing transient three-dimensional combustion flow temperature field distribution and outputting the transient three-dimensional combustion flow temperature field distribution. According to the method, the micro-lens array is utilized and matched with the Kalman filtering algorithm, so that the combustion flow field can be measured more effectively, and the defects of a traditional method are overcome.

The invention provides a light field resolution method and system, and relates to the technical field of ultrafast light field imaging. The light field resolution method comprises the following steps: carrying out delay processing on a reference light beam to obtain a delayed reference light beam; delaying the probe light beam to obtain a delayed probe light beam; enabling the delayed probe light beam to pass through an ultrafast event scene to obtain a modulated probe light beam; performing interference on the modulation probe light beam and the delay reference light beam to obtain an image formed by interference; and based on the image formed by interference, obtaining three-dimensional space distribution at different times in the ultrafast event scene. And under the condition that the three-dimensional space distribution is obtained, analyzing the physical characteristics of the ultrafast event scene. Through three-dimensional space distribution, the morphology and characteristics of an ultrafast event scene are analyzed from multiple dimensions of time, space and the like, and a specific relation between a laser parameter and a laser propulsion coupling coefficient can be established.

The invention relates to the technical field of optical imaging, and discloses an automatic aberration correction system and method for remote sensing light field imaging, and the method comprises the steps: constructing an aberration sensitive feature set through dynamic projection coding and multispectral synchronous collection, and improving the aberration perception capability of a complex scene in combination with polarized light information; establishing a three-dimensional aberration field model based on a light field gradient decomposition and multi-focal length coupling model; calculating an optimal focusing parameter and a digital phase compensation mask in combination with physical driving optimization and data driving compensation; and dynamic adaptive correction is realized based on real-time aberration monitoring and light field entropy minimization optimization. According to the method, aberration such as spherical aberration, coma aberration and curvature of field can be effectively inhibited, and the resolution and depth estimation precision of remote sensing light field imaging are improved.

The application relates to an improved cage type light field imaging system and a debugging method, and belongs to the technical field of light field imaging. The system comprises a main lens for collecting light spots on an object plane and imaging light emitted by the light spots onto a microlens; the microlens is used for separating the light collected by the main lens into light beams in different directions and imaging the light beams onto a virtual image plane; a relay lens is used for twice imaging the light beams in different directions onto different pixels of a CCD detector of a camera; the relay lens comprises a first lens and a second lens, the focal lengths of the first lens and the second lens are both positive, the focal length of the first lens is smaller than that of the second lens, and the magnification of the relay lens is greater than 1:1. During the debugging process of the system, parallel light beams are arranged in front of the microlens, and the parallel light beams are vertically injected into the microlens to determine the position of the microlens. The system is not affected by the vignetting and distortion generated by the relay lens, and the debugging method improves the positioning accuracy of the microlens.

This application discloses a method and system for synchronous testing of metasurface grating waveguide performance, relating to the field of metasurface grating technology. The method includes polarization state modulation and spatial frequency encoding of multi-wavelength incident beams to obtain a modulated incident light field; coupling this modulated incident light field into the metasurface grating waveguide under test, which then undergoes total internal reflection to form the outgoing light field; acquiring a raw dataset of the entire light field, including Stokes polarization images and spatial spectrum images corresponding to each wavelength of the outgoing beam; calculating the total internal reflection hop count based on the Stokes polarization image; calculating the spatial step size offset based on the spatial spectrum image; and establishing a mapping relationship between the image pixel coordinates of the raw dataset and the internal physical regions of the metasurface grating waveguide under test to obtain local diffraction efficiency distribution data. This application solves the problem that traditional outgoing end intensity testing is difficult to trace to local defects inside the waveguide, achieving synchronous, high-precision quantitative characterization of local diffraction efficiency across multiple wavelengths.

A light field imaging device and method are provided. The device can include a diffraction grating assembly receiving a wavefront from a scene and including one or more diffraction gratings, each having a grating period along a grating axis and diffracting the wavefront to generate a diffracted wavefront. The device can also include a pixel array disposed under the diffraction grating assembly and detecting the diffracted wavefront in a near-field diffraction regime to provide light field image data about the scene. The pixel array has a pixel pitch along the grating axis that is smaller than the grating period. The device can further include a color filter array disposed over the pixel array to spatio-chromatically sample the diffracted wavefront prior to detection by the pixel array. The device and method can be implemented in backside-illuminated sensor architectures. Diffraction grating assemblies for use in the device and method are also disclosed.

Described are embodiments of a multi-layer giga-pixel plenoptic camera that enable three-dimensional (3D) light-field imaging, high resolution and large field-of-view. In embodiments, the camera includes a radiation conversion array layer, an optics array layer, a complementary metal-oxide-semiconductor (CMOS) image sensor array layer, and a memory layer. Depending on the embodiment, the sequence of the radiation conversion array layer and the optics array layer may be reversed, and / or additional isolation layers may be provided between some of the layers. Applications can span the visible light spectrum, and can include ultraviolet (UV) and infrared (IR) spectra. In an embodiment, applications can span x-ray spectra and gamma ray spectra. Radiation converters in the radiation conversion array layer can be filters or scintillation converters. Optics in the optics array layer can be lenses or pinholes and / or coded apertures.

The light field imaging device of the present invention may comprise: a linear polarizing plate; a first polarization switching element on which light passing through the linear polarizing plate is incident and which is electrically controlled to be turned on / off; a quarter-wave plate on which the light passing through the first polarization switching element is incident; and a first geometric phase lens on which the light passing through the quarter-wave plate is incident.

The application relates to the technical field of imaging devices, and particularly discloses a light field imaging device and method, which comprises a main lens configured to receive light rays in a scene and refract to form a first image; a diffraction element arranged on the side of the main lens away from the scene, the diffraction element is arranged in an array and has a plurality of diffraction elements, the diffraction element is configured to perform isofocal diffraction focusing on monochromatic light of a target wavelength in the first image to form focused light rays; a light filtering element arranged on the side of the diffraction element away from the main lens, the light filtering element is configured to receive the focused light rays and allow the monochromatic light to pass through the light filtering element; and an image sensor arranged on the side of the light filtering element away from the diffraction element, the image sensor is configured to receive the monochromatic light passing through the light filtering element to form an element image. The light field imaging device and method can effectively eliminate imaging chromatic aberration and reduce the cost.

The present invention relates to a high-resolution light field image reconstruction method, device, electronic device and storage medium, and belongs to the field of light field imaging technology. The present invention utilizes the electrically controlled focusing characteristics of a liquid crystal microlens array to realize the acquisition of different light field images. The acquisition process does not require frequent movement of the liquid crystal microlens array, which can reduce the acquisition time of the light field image and the required manpower and material resources, thereby improving the efficiency of the above-mentioned high-resolution light field image reconstruction method, and utilizes light field images at different focus positions to reconstruct high-resolution light field images based on a signal recovery method, so that the reconstruction process of the high-resolution light field image does not require the introduction of a high-resolution network, thereby making the above-mentioned high-resolution light field image reconstruction method easier to implement.

The invention provides a visual field depth expanding method based on sparse scanning of a light field microscope, which comprises the following steps of: performing sparse scanning on a sample in X, Y and Z axial directions by utilizing a micro-lens array light field imaging system, enabling the overlapping rate between adjacent visual fields to be lower than a preset value, and acquiring multi-visual-field two-dimensional original light field data; performing pixel rearrangement and deconvolution three-dimensional reconstruction on the two-dimensional original light field image of each view to obtain a reconstructed three-dimensional body of each view; calculating the theoretical overlapping region width in the XYZ axial direction according to the sparse scanning step length, and carrying out consistency calibration on the overlapping region in the XYZ axial direction of the adjacent visual fields; and carrying out recursive fusion on the calibrated reconstructed three-dimensional body along the X, Y and Z axial directions to obtain a full-view-field and full-depth-of-view three-dimensional body image. According to the invention, not only can a larger imaging depth range be provided, but also the image definition at different depth levels can be ensured, and the inherent depth-of-field limitation of a traditional optical system is overcome.

The application discloses a kind of optimization method and device for motion artifact in scanning light field imaging, the method includes the following steps: obtaining the single-frame original light field image to be optimized;Original light field image is rearranged as space-angle image according to space and angle information by pixel rearrangement;Periodic scanning is carried out to space-angle image, and subpixel in different space positions and angle directions is obtained, and pixel is realigned;According to scanning order, the image after realignment is disassembled, and multiple space-angle subgraphs in time dimension are obtained;Space-angle subgraph is input into the scanning correction network trained, image correction fusion is carried out, and high-resolution space-angle image removing motion artifact is obtained;Scanning correction network is based on neural network model construction.The application is processed by pixel rearrangement, periodic scanning, pixel realignment and disassembly, and then input into scanning correction network, while eliminating motion artifact, the higher spatial resolution of image is maintained.

The present invention discloses an optical field imaging system and an optical field acquisition method in the terahertz band, which include at least one imaging module, at least one light source module, a positioning and adjustment module, and a control and processing module. The imaging module is used to convert the spatial information of the imaging target in the scene into a projected two-dimensional image; the positioning and adjustment module is used to control the position and attitude of the imaging module in space, and the camera optical characteristics including but not limited to the aperture of the diaphragm and the distance between the focal plane and the lens group; the positioning and adjustment module of the optical imaging system is used to achieve precise positioning of the imaging module, realize detailed quantitative exploration and measurement of the complex spatial complex refractive index distribution inside the object, and the application range of the optical field imaging system of the present application is wider than that of relatively simple imaging systems.

The invention belongs to the technical field of computer vision and light field imaging, and discloses a large-area highlight detection and repair method and system. The method comprises the following steps: imaging by using a light field camera array to obtain a multi-view-angle light field image, and calculating an initial parallax; the method comprises the following steps: obtaining a multi-view highlight area mask through highlight detection, removing the highlight area mask to obtain a light field image without a highlight area, carrying out light field refocusing to obtain a non-highlight refocusing image stack, applying the highlight area mask obtained through central view angle detection to an initial parallax image, and constructing a reliable parallax set to realize parallax layering; according to parallax layer information of a non-highlight area pixel adjacent to a highlight pixel space in the highlight area, carrying out adaptation on a parallax layer of the highlight pixel; and constructing a hierarchical restoration strategy based on observation conditions of different viewpoints when no-highlight refocusing image of the highlight pixel in the corresponding parallax layer is superposed and averaged at the pixel position, thereby realizing restoration of the highlight area. According to the method, high-quality and large-area highlight repair can be realized.