12 results about "Pinhole collimator" patented technology

The invention provides an SPECT pinhole collimator imaging truncation artifact filling method and related equipment, and relates to the technical field of CT imaging. The method comprises the following steps: reconstructing real projection data to obtain an original reconstructed image, and determining a high-confidence region in the original reconstructed image; mapping the real projection data to a projection image of an ideal detector radial distance to obtain mapping projection data; predicting projection data outside an effective area of a real acquisition detector and taking the projection data as simulation projection data; carrying out weighted reconstruction on the simulation projection data to obtain a complemented image containing a truncation region; and according to the high-confidence region, fusing the original reconstructed image and the complemented image to obtain a final image. The method aims at solving the problem of truncation artifacts caused by the fact that the probe cannot completely cover the whole human body projection image, negative effects caused by the truncation artifacts can be made up, and the effect of improving the imaging quality and the diagnosis accuracy is achieved.

There is provided a transmission X-ray diffraction (XRD) apparatus, the transmission XRD apparatus including an X-ray source for generating a direct X-ray beam; sample holder for receiving the sample, the sample being positioned to receive the direct X-ray beam when held by the sample holder; a detector for receiving X-rays transmitted through the sample and outputting an X-ray diffraction pattern therefrom; and an optical element positioned between the X-ray source and the detector, the optical element including a Montel optic and a secondary pin-hole collimator collectively adapted to focus the direct X-ray beam on the detector, wherein a ratio between a dimension of the direct X-ray beam projected on the detector and a sample-to-detector distance is equal or smaller than 1 / 570. Related methods are also provided.

This invention provides a dual-aperture multi-pinhole collimator, comprising: a collimator plate; and multiple pinholes of two different apertures spaced apart on the collimator plate. During a single imaging process, radioactive rays passing through the imaging fields of different apertures simultaneously form corresponding and non-overlapping projection responses on the detector. Of the two apertures, the first aperture is smaller than the second aperture. The first aperture is determined based on the desired system spatial resolution, and the second aperture is determined based on the desired detection efficiency. This invention also proposes a SPECT imaging system based on the aforementioned multi-pinhole collimator. Its imaging module obtains imaging results from the data required for tomographic reconstruction using an improved MLEM iterative algorithm. The improved MLEM iterative algorithm introduces weighting factors into the original MLEM iterative algorithm, weighting the projection data of the dual-aperture pinholes and the corresponding system transmission matrix elements respectively. This invention improves detection sensitivity while maintaining spatial resolution.

The invention discloses a parallel pinhole collimator in the technical field of collimator casting, the collimator is integrally cast and formed by lead alloy, the parallel pinhole collimator further comprises a casting device of the parallel pinhole collimator, the casting device comprises a telescopic cylinder, an upper die and a lower die, a lower jacking mechanism is installed at the top of the lower die, and the lower jacking mechanism is connected with the telescopic cylinder. The top of the upper die is connected with an upper jacking mechanism, and the output end of the telescopic cylinder is connected with the upper jacking mechanism; through the arrangement of the lower jacking mechanism and the upper jacking mechanism, the collimator can be automatically ejected downwards from the interior of the upper mold and automatically ejected upwards from the interior of the lower mold during mold opening of the telescopic cylinder, effective demolding of the collimator is guaranteed, and therefore the quality of the collimator is guaranteed.

The utility model relates to an SPECT (Single Phase Emission Computed Tomography) multi-pinhole collimator, a combined collimator and a detection device. The SPECT multi-pinhole collimator comprises a single pinhole collimator module and at least two multi-pinhole collimator modules. The SPECT multi-pinhole collimator comprises a single pinhole collimator module and two to three multi-pinhole collimator modules. The SPECT multi-pinhole combined collimator comprises two SPECT multi-pinhole collimators which are arranged in parallel and opposite to each other. The two SPECT multi-pinhole collimators are respectively arranged on transverse guide rails capable of enabling the SPECT multi-pinhole collimators to transversely move; and each transverse guide rail is arranged on the combination of the threaded lead screw and the guide rail. The SPECT detection device is provided with two opposite detectors, each detector is fixed in a detector frame, the SPECT detection device comprises an SPECT multi-pinhole combined collimator, and the two detectors are also arranged on the combination of the threaded lead screw and the guide rail.

The utility model discloses a collimation mechanism which comprises a movable supporting vehicle body and a collimator, and the collimator is fixedly connected to the top of the supporting vehicle body. The collimator is an arc-shaped structure plate body formed by splicing a plurality of collimator flat plates, the adjacent collimator flat plates are in lap joint, each collimator flat plate is at least provided with one collimator hole, the axes of the different collimator holes intersect at the center of a chord of the arc-shaped structure plate body, and the collimator is a pinhole collimator. According to the collimation mechanism, view waste is avoided, imaging efficiency is improved, different small organs can be imaged, and universality is better. The utility model further discloses medical imaging equipment.

The super-hole collimator for gamma photon detection and the nuclear medicine imaging system provided by the utility model are provided with the collimator plate, the plurality of collimating holes which are irregularly distributed or randomly distributed are formed in the collimator plate, and when radioactive rays in an imaging view pass through the collimating holes and then form projection overlapping on a gamma photon detector, the radioactive rays are irradiated by the gamma photon detector. The orientation of the collimation hole should meet the requirement that the normal vector of the central plane of the collimation hole passes through the center of the imaging view, and the field angle of the collimation hole should meet the requirement that the extension lines of the two edges of the collimation hole are tangent to the imaging view. According to the multi-pinhole collimator, the limitation of a pinhole arrangement mode in a traditional multi-pinhole collimator on the number of pinholes is effectively overcome, a certain number of collimation holes are randomly arranged on the collimator, and the number of the collimation holes is far larger than that of the pinholes in the existing multi-pinhole collimator; the projection overlapping area of radioactive rays on the detector after passing through all the collimation holes in the imaging view field is improved, a super-hole collimator is formed, and the detection efficiency is remarkably improved on the premise that the image resolution is guaranteed.

The application provides an inorganic scintillation crystal performance test system and method based on an adjustable pinhole collimator, and solves the problem that existing inorganic scintillation crystal performance test systems are mostly limited to the research of specific crystals and radioactive sources and are not universal in radiation detection macroscopic applications. The system comprises a base, a radioactive source, a radioactive source limiting unit, a collimation assembly, a collimation adjusting unit, a detector position adjusting unit and a rear-end test unit. Through the use of the system core structure, the collimation assembly composed of multiple pinhole collimators, the radioactive source radiation is accurately injected into the scintillation crystal at a certain angle, reducing the interference caused by scattering and environmental background, and combining standard scintillation crystals and standard radioactive sources of the same kind, the activity and energy consistency of the radioactive source is calibrated with high precision and sensitivity, and then flexible matching of various types of radioactive sources is realized, and the objective conditions of the numerous radiation isotopes in the application environment are restored as much as possible.

The invention discloses a pinhole collimator configuration method, scanning equipment, an imaging method of the scanning equipment and a medium. The pinhole collimator configuration method comprises the following steps: acquiring an imaging simulation model, and a radioactive source, a pinhole collimator and a detector which are defined in the imaging simulation model; constructing a plurality of different parameter configuration schemes based on the collimator configuration parameters corresponding to the pinhole collimator; performing simulation processing in the imaging simulation model according to a plurality of different parameter configuration schemes and the radioactive source, and collecting a plurality of groups of projection data projected to the detector; and performing image reconstruction based on the plurality of groups of projection data to obtain a plurality of reconstructed images, screening out a target reconstructed image meeting a preset index requirement from the plurality of reconstructed images, and taking a parameter configuration scheme corresponding to the target reconstructed image as an optimal configuration scheme corresponding to the pinhole collimator. According to the optimization configuration method of the pinhole collimator, the sensitivity can be greatly improved by using the optimized pinhole collimator, and the contrast ratio of the reconstructed image is increased.

The invention provides a super-hole collimator for gamma photon detection, the super-hole collimator is provided with a collimator plate, a plurality of collimating holes which are irregularly distributed or randomly distributed are formed in the collimator plate, and when radioactive rays in an imaging view pass through the collimating holes, projection overlapping is formed on a gamma photon detector. And the superposition of the projection areas is at least two times of the detection area of the gamma photon detector. According to the multi-pinhole collimator, the limitation of a pinhole arrangement mode in a traditional multi-pinhole collimator on the number of pinholes is effectively overcome, a certain number of collimation holes are randomly arranged in the collimator, and the number of the collimation holes is far larger than that of the pinholes in the existing multi-pinhole collimator; according to the invention, the projection superposition area of radioactive rays in an imaging field of view on the detector through all the collimation holes meets the requirement, a super-hole collimator is formed, and the detection efficiency is obviously improved on the premise of ensuring the image resolution, so that the counting of gamma photons collected in unit time is improved, and the imaging collection time is effectively shortened.

The present invention discloses a multi-pinhole collimator with multi-functional self-conversion and its operation method, which includes an outer shielding component, an inner shielding component and a motion component; the outer shielding component includes an outer shielding cylinder and an outer shielding frame, the inner shielding component includes an inner shielding cylinder and an inner shielding frame, and the inner shielding cylinder is sleeved inside the outer shielding cylinder through the inner shielding frame and the outer shielding frame; the motion component is a device for driving the relative displacement of the inner shielding cylinder and the outer shielding cylinder along their own central axes; multiple rows of pinholes are arranged along the central axis direction of the inner shielding cylinder, and the pinholes in the same row are distributed circumferentially along the inner shielding cylinder, and the apertures and hole pitches of the multiple rows of pinholes are different from each other. Through the relative movement of the inner shielding cylinder and the outer shielding cylinder, the multi-functional and rapid and flexible changes and switching of different resolutions, different perspectives, different fields of view, different sensitivities, etc. are realized, and the cumbersome work of replacing another collimator due to the need to replace collimators with different functions is eliminated.

The invention provides an inorganic scintillation crystal performance test system and method based on an adjustable pinhole-shaped collimator, and solves the problem that the existing inorganic scintillation crystal performance test system mostly stays at the research level of specific crystal and radioactive source conditions and does not have universality in the macroscopic application of radiation detection. The system comprises a base, a radioactive source, a radioactive source limiting unit, a collimation assembly, a collimation adjusting unit, a detector position adjusting unit and a rear-end testing unit. Through use of a system core structure, namely a collimation assembly composed of a plurality of pinhole-shaped collimators, radiation rays of a radioactive source are accurately emitted into a scintillation crystal at a determined angle, interference caused by scattering of the radiation rays and an environment background is reduced, and the detection accuracy is improved by combining a standard scintillation crystal and a standard radioactive source of the same kind. High-precision and sensitivity calibration of activity and energy consistency of the radioactive source is realized, flexible matching of various radioactive sources is further realized, and objective conditions of various radioactive isotopes in an application environment are restored as much as possible.