53 results about "Pinhole collimator" patented technology

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.

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 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.

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.

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.

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 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.

The present invention relates to a variable pinhole collimator and a radiographic imaging device using the same. The variable pinhole collimator according to the present invention comprises a plurality of pinhole plates in each of which a plurality of pinhole formation holes having mutually different sizes are formed along a circumferential direction and a plurality of rotation operation holes areformed around a rotational axis and along the circumferential direction, and which are stacked in a direction in which radiation is incident; and a driving module drawn into the plurality of rotationoperation holes in the plurality of pinhole plates sequentially in the incident direction, for rotating the plurality of pinhole plates about the rotational axis, wherein the plurality of pinhole plates are rotated, thereby forming a pinhole in an overlapping area. Accordingly, various pinhole shapes can be achieved since it is possible to change a pinhole-configuring parameter of the variable pinhole collimator.

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.

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 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.