53 results about "Pinhole collimator" patented technology

A pinhole collimator is provided that eliminates or at least minimizes the need for collimator exchange, to manage system sensitivity versus spatial resolution tradeoff, and to control imaging FOV (field of view) depending on object size by controlling the focal length of the collimator. There is also provided a detector system is that includes a detector, a collimator, and means for changing the focal length. Various means for changing the focal length are also identified. The collimator can have a plurality of apertures in a top plate, each aperture with its own collimator septa. Additionally, there is provided a medical imaging system that includes the detector system and collimator of the present invention. The nuclear medical imaging systems can have a hand-held detector assembly and be portable.

A multi-pinhole collimator nuclear medical imaging detector divides a target object space into many non-overlapping areas and projects a minified image of each area onto a segmented detector, where each segment functions as an independent detector or imaging cell. Septa may be provided between the collimator and the detector, to physically isolate the segments.

A preclinical nuclear imaging detector system, including a gantry and one or more detector assemblies, each including a scintillator configured to interact with radiation emanating from a target test object being imaged and at least one pinhole collimator, having one or more pinhole apertures formed therein. The pinhole collimator is disposed between the target object and the scintillator, wherein a distance between the pinhole aperture and the scintillator is selected as a function of the number of pinhole apertures provided in the collimator and to optimize one of sensitivity or spatial resolution, such that the one or more pinhole apertures collectively project a unitary minified radiation image of the target object onto the scintillator. Further, one or more photosensors are optically coupled to the scintillator to receive interaction events from the scintillator.

Embodiments relate to pinhole collimator assemblies having one or more adjustable size pinhole apertures therein. The pinhole collimator assembly is configured so that gamma rays can pass through the collimator assembly, but the remainder of the collimator assembly is substantially gamma ray absorbent. Embodiments also relate to imaging systems and methods of adjusting pinhole collimator performance.

The invention belongs to the field of Gamma ray radiation measurement, particularly relates to a Gamma ray imaging device which comprises a Gamma camera and a data acquisition processing system, wherein the Gamma camera comprises a pinhole collimator, a scintillation crystal, a position sensitive photo-multiplier tube and resistor grids; and electrical signals output by the resistor grids are input to the data acquisition processing system arranged outside the Gamma camera. The Gamma ray imaging device produced according to the technical scheme of the invention can measure the large-scaled decommissioning site of nuclear facilities in real time to obtain a region distribution map of hot points, which includes nuclide positioning, nuclide identification and nuclide dosage.

A tomography device, particularly for single photon emission computed tomography (SPECT), comprises a multi-pinhole collimator and a detector for detecting gamma quanta or photons that penetrate the multi-pinhole collimator. In a tomographic method using the device, the distance between the object and the multi-pinhole collimator is selected to be smaller than the distance between the multi-pinhole collimator and the surface of the detector.

Briefly described, in an exemplary form, the present invention discloses a system, method and apparatus for X-ray Compton scatter imaging. In one exemplary embodiment, the present invention uses two detectors in a volumetric CT system. A first detector is positioned generally in-line with the angle of attack of the incoming energy, or, generally in-line of path x, where x is the path of the incoming energy. The first, or primary, detector detects various forms of radiation emanating from an object undergoing testing. In some embodiments, the present invention further comprises a Compton scattering system positioned generally normal to path x. In some embodiments, the Compton scattering subsystem comprises a second detector and a pin-hole collimator. The second detector detects Compton scattering energy from the object being tested.

A highly directional radiation probe with a laser guide to pinpoint the position of a source of radiation. The probe is configured with a lead pinhole collimator, a radiation detector configured to detect radiation through the pinhole, and a laser positioned in the collimator and configured to project a beam through the pinhole. When the probe is aligned with the radiation source detected through the pinhole, the laser is activated and projects a beam at the source position. The probe can scan a person in three dimensions to quickly locate radioactive shrapnel for removal. The probe can also be used to pinpoint small sources of radiation in a localized area within a radius up to about 20 meters or further, depending on the level of radiation exposure encountered. The probe is adapted to be hand-held, battery-operated and used with a visual or audible radioactivity indicator or a visual display device.

A computed tomography apparatus is provided that includes a single photon emission computed tomography (SPECT) multi-pinhole collimator, where the multi-pinhole collimator includes an aperture plate and a grid pattern of pinholes disposed in the aperture plate, and the pinholes include through-holes each having a central axis pointing at a common focal point at a finite distance from the aperture plate. The multi-pinhole collimator is disposed for radionuclide imaging using nuclear medicine therapies that include TI-201, Tc-99m, I-123, In-111 or I-131. Here, the radionuclide imaging can include brain radionuclide imaging, cardiac radionuclide imaging, bladder radionuclide imaging, thyroid radionuclide imaging, breast radionuclide imaging, prostate gland radionuclide imaging, or adrenal gland radionuclide imaging. The grid pattern includes up to 5 pinholes across the aperture plate and up to 4 pinholes down the aperture plate. The aperture plate includes a form factor having dimensions that fit into an imaging SPECT scanner.

Apparatus and methods for determining a system matrix for pinhole collimator imaging systems are provided. One method includes using a closed form expression to determine a penetration term for a collimator of the medical imaging system and determining a point spread function of the collimator based on the penetration term. The method further includes calculating the system matrix for the medical imaging system based on the determined point spread function.

The present invention discloses an integral anatomical and functional computed tomography imaging system, which includes an x-ray source, a rotational stand for a sample and an imager. The imager includes an x-ray and a gamma-ray scintillator, an image sensor for detecting photon from the scintillator and a pinhole collimator positioned between the rotational stand and the scintillator. During the anatomical imaging process, the x-ray penetrating through the sample will directly irradiate on the scintillator in x-ray mode. During the functional imaging process, the gamma-ray emitted from the radioisotope-injected sample will penetrate through the pinhole of the pinhole collimator and then irradiate on the scintillator in gamma-ray mode. For both cases, photons are generated by the scintillator and picked up by the image sensor.

Imaging detectors and methods of manufacturing are provided. One imaging detector includes a first detector layer within a detector module and a second detector layer within the detector module and spaced apart from the first detector layer, wherein the second detector layer has an opening therethrough. The imaging detector also includes a collimator mounted to the detector module, wherein the collimator is one of a single pinhole collimator or a multi-pinhole collimator. Additionally, the second detector layer is mounted within the detector module closer to an opening of the collimator than the first detector layer.

The invention belongs to the field of a radiation measuring technique, in particular to a radiation imaging system based on a photoluminescence image plate with a radiation memory function, which comprises a masking frame body, a pinhole collimator, a position sensitive optical detection module and a control and image processing module, wherein the pinhole collimator is arranged at the front end of the masking frame body; the position sensitive optical detection module is arranged at the back end of the masking frame body, and the optical detection surface of the position sensitive optical detection module is over against to the pinhole collimator; the control and image processing module is connected with the position sensitive optical detection module; an image plate made of a photoluminescence material with the radiation memory function is arranged between the pinhole collimator and the position sensitive optical detection module; an excitation light source corresponding to the photoluminescence material is arranged at the back end of the masking frame body; and a shutter is arranged at the back end of the masking frame body. The radiation imaging system of the invention can measure X-rays or gamma rays with extremely low strength and can be widely used for measuring the radiation strength and the radiation distribution in low-radiation sites.

The invention relates to a manufacturing method of a collimator. The problems that the shape of a pinhole of an existing pinhole collimator is not ideal, so that low-energy scattering of heavy ion microbeams is serious, heavy ion beam spots are large, and the application needs can not be met are solved. The manufacturing method of the pinhole collimator includes the following steps: 1) blade grinding, the top ends of cutting edges of blades are ground to be smooth and clean by using precision abrasive paper; 2) slit structure splicing, the cutting edges of the two blades are oppositely fixed on a bottom liner, and a slit is reserved between the cutting edges; 3) assembling, two slit structures are fixed together in an overlaying mode to form the pinhole of the pinhole collimator. The top ends of the cutting edges of the blades of the pinhole collimator manufactured according to the manufacturing method are good in straightness, the width of the spliced slit can be smaller than 1 micron, low-energy scattering ingredients of the heavy ion microbeams can be better lowered, the generated heavy ion beam spots are good in quality, and the application in heavy ion microbeam irradiation equipment is well achieved.

The invention relates to a collimator, and solves the problems that the conventional pinhole collimator is undesirable in pinhole shape, so that low-energy scattering of heavy ion microbeams is serious, spots of the heavy ion beams are overlarge, and application requirements cannot be met. The pinhole collimator provided by the invention comprises an upper end liner, a first slit structure, a second slit structure and a lower end liner; the first slit structure as well as the second slit structure comprises two blades which are arranged in the same plane and the cutting edges of the blades are opposite to each other; a slit is reserved between the opposite cutting edges; the cutting edges are required to be thick enough to prevent transmission of an object to be collimated. The pinhole collimator provided by the invention has the advantages that the straightness of the top ends of the cutting edges of the blades is good, and the width of a spliced slit can be smaller than 1 Mum, so that the low-energy scattering ingredients of the heavy ion microbeams can be reduced better, the spots of the heavy ion beams are good in quality, and the application of the pinhole collimator in heavy ion microbeam irradiation devices is realized better.

The invention discloses a multifunctional self-conversion multi-pinhole collimator and an operating method thereof. The multi-pinhole collimator comprises an external shielding component, an internalshielding component and a motion component. The external shielding component comprises an external shielding barrel and an external shielding frame; the internal shielding component comprises an internal shielding barrel and an internal shielding frame; the internal shielding barrel internally sleeves the external shielding barrel through the internal shielding frame and the external shielding frame; the motion component is a device which drives the internal shielding barrel and the external shielding barrel to generate relative displacement along own center axis; the internal shielding barrelis provided with a plurality of rows of pinholes along the direction of own center axis, the pinholes in the same row are peripherally distributed along the internal shielding barrel, and the rows ofthe pinholes are different in diameter and distance. By relative motion of the internal shielding barrel and the external shielding barrel, multifunctional quick and flexible changing and conversionof different resolutions, different view angles, different view fields, different sensitivities and the like can be realized, and complicated operation of mounting another collimator due to requirement of replacement of collimators with different functions is avoided.

The invention discloses a heavy-loaded precise centering adjustment device for a thick pinhole collimator. The heavy-loaded precise centering adjustment device is characterized in that a front-end support of the thick pinhole collimator is formed after a Y-axis adjustment mechanism I, a Z-axis adjustment mechanism I and a planar spherical hinge mechanism are combined; a tail-end support of the thick pinhole collimator is formed after a Y-axis adjustment mechanism II, a Z-axis adjustment mechanism II and a tail pressing seat mechanism are combined; the front end of the thick pinhole collimatoris fixedly arranged in the center position of the planar spherical hinge mechanism, and the tail end of the thick pinhole collimator is connected with the tail pressing seat mechanism. According to the heavy-loaded precise centering adjustment device disclosed by the invention, the adjustment accuracy is increased through bevel gear combination, harmonic deceleration and driving hand wheel combination, and a self-locking function after adjustment is completed is realized; the tail pressing seat mechanism adopts a spherical support and an upper pressing block spring locking structure, so that drift of a light spot during a locking state can be avoided; determination on relative positions of a laser spot of a reference optic axis of the thick pinhole collimator and the center of a front collimating hole of an imaging plate can be realized, and the situation that the diameter of a field of view can be obtained by measuring the position of an arc-shaped edge in an image of the imaging plate can be realized.

A detector assembly is provided that includes a semiconductor detector, a pinhole collimator, and a processing unit. The semiconductor detector has a first surface and a second surface opposed to each other. The first surface includes pixels, and the second surface includes a cathode electrode. The pinhole collimator includes an array of pinhole openings corresponding to the pixels. Each pinhole opening is associated with a single pixel of the semiconductor detector, and the area of each pinhole opening is smaller than a corresponding area of the corresponding pixel. The processing unit is operably coupled to the semiconductor detector and configured to identify detected events within virtual sub-pixels distributed along a length and width of the semiconductor detector. Each pixel includes a plurality of corresponding virtual sub-pixels (as interpreted by the processing unit), wherein absorbed photons are counted as events in a corresponding virtual sub-pixel.

An open-gantry structure of SPECT imaging system for scanning human small organs or small animals and method for preparing the system is disclosed. The system contains an imaging desk that one or multiple detector heads are rotated around the object to be scanned while tilted under the imaging desk and dedicated image reconstruction algorithm was developed for the system in case of applying single pinhole collimator.

The invention belongs to the technical field of radiation measurement, in particular to a radiation imaging system based on a radiophotolumine scene image board with a radiation memorizing function. The system comprises a shading frame, a pinhole collimator, a position sensitive optical detection module and a controlling and image processing module, wherein the pinhole collimator is arranged at the front end of the shading frame; the position sensitive optical detection module is arranged at the rear end of the shading frame, and the optical detection surface of the position sensitive opticaldetection module is over against the pinhole collimator; the controlling and image processing module is connected with the position sensitive optical detection module; an image plate made of a radiophotolumine scene material is also arranged between the pinhole collimator and the position sensitive optical detection module; the rear end of the shading frame is provided with a laser light source corresponding to the radiophotolumine scene material; and the rear end of the shading frame is also provided with a shutter. The radiation imaging system can be used for measuring X-rays or gamma-rays with extremely low intensity and can be widely applied to imaging the radiation intensity and the radiation imaging in a low-radiation place.

A detector assembly is provided that includes a semiconductor detector, a pinhole collimator, and a processing unit. The semiconductor detector has a first surface and a second surface opposed to each other. The first surface includes pixelated anodes. The pinhole collimator includes an array of pinhole openings corresponding to the pixelated anodes. Each pinhole opening corresponds to a corresponding group of pixelated anodes. The processing unit is operably coupled to the semiconductor detector and configured to identify detected events from the pixelated anodes. The processing unit is configured to generate a trigger signal responsive to a given detected event in a given pixelated anode, provide the trigger signal to a readout, and, using the readout, read and sum signals arriving from the given pixelated anode and anodes surrounding the given pixelated anode.

The invention relates to a low-scattering X-ray fluorescence CT imaging system and method. The system comprises a light source, X-ray fluorescence detectors, and a data processing system. The light source is a fan-shaped beam X-ray source. The detectors are eight minitype fluorescent detectors and are classified into two groups; and each group includes four detectors. Pinhole collimators are addedin front of the detectors and are arranged at the two sides of an incident X-ray beam symmetrically; and an included angle between the collimators and the incident X-rays are 90 to 180 degrees. Fluorescent light passes through the pinhole collimators and then is received by the fluorescence detectors; the data processing system carries out conversion to obtain projection data; and then an elementdistribution structure chart of the sample is reconstructed. Therefore, the resolution and contrast of different soft tissues of medical CT images can be increased; and the interference on the photons by the Compton scattering can be reduced.