31 results about "Absorption contrast" patented technology

The principle of reciprocity states that full-field and scanning microscopes can produce equivalent images by interchanging the roles of condenser and detector. Thus, the contrast transfer function inversion previously used for images from scanning systems can be applied to Zernike phase contrast images. In more detail, a full-field x-ray imaging system for quantitatively reconstructing the phase shift through a specimen comprises a source that generates x-ray radiation, a condenser x-ray lens for projecting the x-ray radiation onto the specimen, an objective x-ray lens for imaging the x-ray radiation transmitted through the specimen, a phase-shifting device to shift the phase of portions of x-ray radiation by a determined amount, and an x-ray detector that detects the x-ray radiation transmitted through the specimen to generate a detected image. An image processor then determines a Fourier filtering function and reconstructs the quantitative phase shift through the specimen by application of the Fourier filtering function to the detected image. As a result, artifacts due to absorption contrast can be removed from the detecting image. This corrected image can then be used in generating three dimensional (3D) images using computed tomography.

The invention discloses a nucleic acid nano structure carrier, a nucleic acid nano structure carrier-precious metal photosensitive contrast agent composite comprising the same, and preparation methods and applications of the carrier and the composite. The nucleic acid nano structure is a random two-dimensional and/or three-dimensional nano structure constructed by a DNA paper-folding technology. The precious metal components are used to carry out DNA modification on the surface of the carrier and selected from one or more of gold nano rods, gold nano shells, silver-coated gold nano rods, and gold nano cages. The provided composite is used as a photo-acoustic imaging probe, is capable of guaranteeing the absorption contrast enhancing effect of the photo-acoustic contrast agent which is coupled to the composite, and moreover can prominently improve the targeting performance of the contrast agent on tumors. Furthermore, the precious metal photosensitive components which are coupled to the carrier are enriched in the inner of tumor tissues, and thus the solved is the problems that conventional contrast agent is distributed over the whole human body or the contrast agent can only stay on the tumor surfaces. The preparation method has the advantages of simple technology, low cost, convenience, and easy application.

A user-friendly, inexpensive radiation image radiographing apparatus capable of easily switching between absorption contrast image radiography and phase contrast image radiography. The radiation image radiographing apparatus has: a radiation source; a subject platform for supporting a subject so as to face the subject to the radiation source; and a plurality of supporting platforms for supporting a radiation image information detecting member at a side opposite to the radiation source with respect to the subject platform, the radiation image information detecting member for detecting radiation image information based on radiation transmitted through the subject, wherein distances between the plurality of supporting platforms and the radiation source are different from each other.

An X-ray imaging system includes an X-ray Talbot; imaging apparatus and an image processing apparatus. The image processing apparatus generates reconstruction images from the moire image taken by the X-ray Talbot imaging apparatus. The reconstruction images include a differential phase image, an absorption image and a small-angle scattering image. The X-ray imaging system performs X-ray Talbot imaging and normal X-ray imaging. X-ray Talbot imaging includes setting an exposure energy of the X-ray Talbot imaging apparatus to a first exposure energy and taking the moire image with the X-ray detector. Normal X-ray imaging includes setting the exposure energy of the X-ray Talbot imaging apparatus to a second exposure energy and taking an absorption contrast image with the X-ray detector by normal X-ray imaging.

The invention discloses a transverse dislocated absorption grating-based X ray grating differential phase contrast imaging method and device. The method comprises the following steps: arranging a Talbot-Lau imaging structure by the novel transverse dislocated absorption grating disclosed by the invention; acquiring the two-dimensional intensity image after X ray penetrates through an object by the imaging structure; and separating the X ray absorption contrast image, differential phase contrast image and scattering contrast image from the acquired two-dimensional intensity image by the Fourier analysis method. Compared with the traditional method, the embodiment of the invention does not need to move the grating, three types of contrast images can be obtained by single exposure, so the imaging time is greatly shortened, the imaging dose is reduced and the imaging efficiency and stability of a system are improved.

The invention provides a calcification imaging method and system. The calcification imaging method comprises the following steps of: transmitting a first ultrasonic wave to a tissue; receiving the echo wave of the first ultrasonic wave and forming the first ultrasonograph of the tissue; transmitting a first light ray onto the tissue to excite a first optical sound; receiving the first optical sound and forming a first optical sound image of a calcification; and overlapping the first ultrasonograph with the first optical sound image to form a first overlapped image for imaging the distribution condition of the calcification in the tissue. Compared with ultrasonic wave and X-ray mammography, the image obtained by the invention has the advantages of no speckle noise, high optical absorption contrast and high ultrasonic wave spatial resolution, and the used light source is non-ionizing radiation, thus having higher safety.

An imaging technology for fuel cells is based on x-ray microscopy. A metrology system images the electrochemical interaction areas of solid-oxide fuel cells (SOFC) in-situ. This system takes advantage of both the penetrating power and elemental absorption contrast of hard x-ray radiation to image the internal interaction areas in a SOFC. The technology can further take advantage of the strong dependence of the x-ray absorption on material type and energy to distinguish the four major material types: cathode, electrolyte, air, and low-Z contaminants such as sulfur.

A method for imaging a tissue of an eye, the method including the steps of providing oblique illumination to the eye by a plurality of light emitting areas of a light delivery device, the plurality of light emitting areas being independently controllable and arranged to direct light towards at least one of a retina and an iris of the eye, causing an output beam from light backscattered from the at least one of the retina and the iris by the oblique illumination, capturing the output beam with an imaging system to provide a sequence of images of a fundus of the eye, and retrieving a phase and absorption contrast image from the sequence of images of the fundus, wherein the sequence of images of the fundus of the step of capturing is obtained by sequentially turning on one or more of the plurality of light emitting areas at a time in the step of providing the oblique illumination.

The invention discloses an X-ray grating differential phase contrast imaging method and device based on a two-dimensional dislocation absorption grating. The method comprises the following steps: arranging a Talbot-Lau imaging structure according to a novel two-dimensional dislocation absorption grating provided in the invention; acquiring a two-dimensional intensity image of X rays passing through an object by virtue of the previous structure; and separating three images from the acquired two-dimensional intensity image by a Fourier analysis method, namely an X-ray absorption contrast image,a differential phase contrast image and a scattering contrast image. Compared with the traditional method, the method in the embodiment of the invention has the advantages that the grating does not need to be moved, the three contrast images can be acquired by virtue of single exposure, the imaging time is greatly shortened, the imaging dose is reduced, and the imaging efficiency and stability ofthe system are improved.

An X-ray image photographing method and apparatus is capable of photographing a high resolution phase contrast image and a high resolution absorption contrast image in a short time by finely adjusting the distance between a specimen and a detector with respect to an X-ray source.

The method enables photographing a fine structure with high space resolution while using an X-ray source having a finite size, and d/L is sufficiently smaller than 1, when L is a distance from an X-ray source to a specimen and d is a distance from the specimen to a detector.

The invention relates to a cone-beam X-ray fluorescence imaging method and system, a terminal and a storage medium. The method comprises the following steps: acquiring a phase contrast projection image of an imaging target through an X-ray phase contrast-fluorescence imaging device, and synchronously acquiring a surface fluorescence image of the imaging target; performing information separation and extraction on the phase contrast projection image to obtain an absorption contrast image, a refraction contrast image and a scattering contrast image of the imaging target, and performing three-dimensional reconstruction on the absorption contrast image, the refraction contrast image and the scattering contrast image respectively; inputting the three-dimensional reconstruction images of the absorption contrast image, the refraction contrast image and the scattering contrast image and the surface fluorescence image into the trained XLCT three-dimensional reconstruction deep convolutional neural network model, and outputting a cone beam XLCT fluorescence image of the imaging target through the XLCT three-dimensional reconstruction deep convolutional neural network model. According to the method, the ill-conditioned degree of solving the cone-beam XLCT three-dimensional reconstruction equation can be effectively reduced, and rapid and high-resolution cone-beam X-ray fluorescence imaging is realized.

The invention relates to the technical field of nondestructive testing of building structures, and discloses a sleeve grouting forming quality detection method based on improvement of X-ray absorption contrast, which comprises the following steps: mixing: putting a grouting material and barium sulfate powder into a stirrer for premixing at the stirring speed of 240-280 r/min for 3 minutes, and after stirring is completed, putting the grouting material and barium sulfate powder into the stirrer for pre-mixing; and taking out about 30% by mass of the mixed grouting material for later use, and adding water accounting for 12% of the sum of the mass of the mixed grouting material into the stirrer for stirring. According to the method, the barium sulfate powder is added into the grouting material, and the barium sulfate powder and the grouting material are fully mixed, so that the absorption contrast of the mixed slurry to X rays is improved, the contrast difference between the grouting material and grouting defects is increased, and accurate judgment of the grouting fullness and the grouting node internal defects is realized; compared with the conventional X-ray detection, the portable X-ray detector has the advantages that the technical progress is realized, and meanwhile, the portable X-ray detector has popularization performance.

The invention discloses a microscopic imaging method for simultaneously obtaining light absorption contrast and light scattering contrast. The method comprises the following steps: focusing pulse laser on a sample, absorbing part of the pulse laser by the sample, exciting an ultrasonic signal due to a photoacoustic effect, and receiving the ultrasonic signal through an ultrasonic transducer whichis confocal with a microscope objective and coaxially arranged to obtain an image with light absorption contrast; and meanwhile, using residual pulse laser penetrating through the sample irradiates the surface of the same ultrasonic transducer after being scattered and absorbed by the sample, so as to excite another ultrasonic signal, receiving the ultrasonic signal by the ultrasonic transducer, and obtaining an image with light scattering contrast. According to the invention, for any imaging point on the sample, light scattering-light absorption bimodal microimaging can be realized at the same time only by one-time light excitation; moreover, the method is a high-resolution imaging technology without an exogenous marker, avoids possible influence of a marker on the properties of the sample, and has higher usability and practicability.

The invention discloses a high-energy X-ray CT device based on phase contrast imaging and an imaging method. The high-energy X-ray CT device comprises a high-energy X-ray source, a sample table and animaging device, wherein the high-energy X-ray source is a high-energy X-ray punctuality light source, is an irradiation light source of a sample and is used for directionally emitting and irradiatingand transmitting the sample; the sample table is used for placing a sample, and after the high-energy X-ray source penetrates through the sample, transmitted X-rays are transmitted in a fluctuation mode and are coherently superposed on an image plane behind the sample to form photon intensity information containing phase and amplitude information; and the imaging device is arranged on an image plane behind the sample and is used for converting photon intensity information into an image signal. According to the method, the problems that the quality of the obtained CT image is not ideal and thespatial resolution is poor due to the existing CT technology based on high-energy X-ray absorption contrast, particularly, the resolution of the obtained image of the micro gap in the product is verylow, the micro gap is visible and unmeasurable, and the micro defects are difficult to distinguish are solved.