Abstract: A zoned radiation device for converging radiation of a wavelength ? to a focus at distance b, the device comprising a first set of zones and a second set of zones, wherein the first set of zones have a different characteristic to the second set and wherein the area of the zones decrease as their distance from a predetermined point increases, and one or more zone distances at which a zone of the first set with a first characteristic switches to a second zone with a second characteristic are configured such that the device can focus the radiation with wavelength ? at a distance b with an autocorrelation/point spread function that is sharper than the autocorrelation/point spread function produced by zones configured to a Fresnel zone construction.

Abstract: A device and method are disclosed for imaging. Coded aperture arrays are used in conjunction with macro-collimators, on either side or both sides of the coded aperture arrays, to produce coded images, which are then used to produce a decoded image. Various parameters, including the distances between the radiation source and the code and between the code and the detector, the relative lengths of macro-collimator tubes, sizes of pin-holes in the coded aperture arrays, and number and sizes of the macro-collimator tubes, can be selected to achieve high resolution images of the radiation source. The macro-collimator eliminates wide angles rays and reduces ghost images in the reconstruction. Combining data sets from two gamma camera heads reduces the noise in OSEM reconstruction by improving the definition of object borders. Rotation of the coded apertures eliminates near field artifacts from the Fourier reconstruction of the image.

Abstract: An apparatus for capturing images. In one embodiment, the apparatus comprises: a coded lens array including a plurality of lenses arranged in a coded pattern and with opaque material blocking array elements that do not contain lenses; and a light-sensitive semiconductor sensor coupled to the coded lens array and positioned at a specified distance behind the coded lens array, the light-sensitive sensor configured to sense light transmitted through the lenses in the coded lens array.

Abstract: An inspection system according to various embodiments can include a stationary mono-energetic gamma source and a detector-spectrometer. The detector-spectrometer is configured to employ a modulation of energy bin boundaries within a multi-channel pulse height analyzer to encode voxels within the inspected object, and apply an analysis to determine the three-dimensional density image of the inspected object.

Abstract: A combined format gamma-ray detector (D) for measuring impinging gamma-rays (10) includes an active upper level coded aperture detector plane member (12) that is suitable for detecting an impinging gamma-ray (10). An active lower level gamma ray detector plane member (14) that is spaced apart from the upper level coded aperture (12) detects an impinging gamma-ray (10). At low gamma-ray energies, the combined format gamma-ray detector device (D) operates as a conventional coded aperture system and at higher gamma-ray energies, the combined format gamma-ray detector device operates as a Compton scattering detector device.

Abstract: This invention relates to coded aperture imaging apparatus and methods. In one aspect a coded aperture imager has at least one detector array and a reconfigurable coded aperture mask means. A reconfigurable coded aperture mask means can display various coded aperture masks to provide imaging across different fields of view and/or with different resolution without requiring any moving parts or bulky optical components. More than one detector array can be used to provide large area imaging without requiring seamless tiling and this represents another aspect of the invention. The present invention also relates to the use of coded aperture imaging in the visible, ultraviolet or infrared wavebands. The use of coded aperture imaging for imaging through a curved optical element is taught as the image decoding can automatically remove any aberrations introduced by the curved element.

Abstract: In coded aperture imaging knowledge of the coded array pattern and its positional relation to the detector array is needed in order to be able to reconstruct the scene image. Usually a theoretical model of the coded array is used and the actual array needs to be aligned accurately with respect to the detector. The present invention uses a coded aperture imager to image a reference object in the scene and uses the intensity pattern on the detector array to determine the decoding pattern corresponding to the coded aperture array. The reference object may be a point source in which case the pattern on the detector array may be used directly as the decoding pattern or it may be used to correct a theoretical pattern for any misalignment.

Abstract: The invention relates to a device limiting the appearance of decoding artefacts for a gamma camera with a coded mask comprising a gamma radiation detector (3) opposite the coded mask (1) and having a field of view with an area partially coded (20) by the coded mask (1). It comprises a recessed part (30), which is opaque to the gamma radiation, to be arranged opposite the detector (3) with respect to the coded mask (1), with said recessed part (30) obscuring the partially coded area (20) of the field of view for the detector (3).

Abstract: A device and method are disclosed for imaging. Coded aperture arrays are used in conjunction with macro-collimators, on either side or both sides of the coded aperture arrays, to produce coded images, which are then used to produce a decoded image. Various parameters, including the distances between the radiation source and the code and between the code and the detector, the relative lengths of macro-collimator tubes, sizes of pin-holes in the coded aperture arrays, and number and sizes of the macro-collimator tubes, can be selected to achieve high resolution images of the radiation source. The macro-collimator eliminates wide angles rays and reduces ghost images in the reconstruction. Combining data sets from two gamma camera heads reduces the noise in OSEM reconstruction by improving the definition of object borders. Rotation of the coded apertures eliminates near field artifacts from the Fourier reconstruction of the image.

Abstract: A three-dimensional image-generating device is an inspection system incorporating three components: a radiation source, a modulating unit, and a radiation detector. All three components of the inspection system may be stationary. The radiation source irradiates an external inspected object with mono-energetic gamma rays. The modulating unit, used in conjunction with the unique energy-angle characteristics of the Compton scattering process, by encoding the gamma rays, enables the identification of the spatial origin of single-scattered gamma fluxes as they pass through the inspected object enroute to the detector. The radiation detector and the computerized processor identify gamma fluxes scattered from various locations within the inspected object. The three-dimensional distribution of scattering locations within the inspected object that produce the detected single-scattered gamma fluxes and their intensity is converted to a three-dimensional mass distribution as an image within the inspected object.

Abstract: In some preferred embodiments, an apparatus is provided that facilitates correction, such as, e.g., linearity correction, in imaging devices, such as, e.g., scintillation cameras. In preferred embodiments, a mask is implemented that can produce images for locating the actual position of a nuclear event based on its apparent position with high accuracy and reliability. In the preferred embodiments, the mask includes a non-uniform array of apertures that can achieve this goal.

Abstract: A sensor for determining a component of a location of a radiation source within a three dimensional volume includes a mask having a series of openings that has a predetermined mathematical relationship among the openings within the series of openings and defines a mask reference line; a detector surface spaced from the mask where radiation passing through the mask creates a mask image on the detector surface having a series of peaks and an image reference line within the mask image that can be located and where at least 50% of the mask image is projected onto the detection surface; and a calculating unit to determine a location of the image reference line within the mask image and the component of the location of the radiation source from the calculated location of the image reference line within the mask image. A method and system for using this sensor are also disclosed.

Abstract: Determining instantaneously the three-dimensional coordinates of large sets of points in space using two or more CCD cameras (or any other type of camera), each with its own lens and pinhole. The CCD's are all arranged so that the pixel arrays are within the same plane. The CCD's are also arranged in a predefined pattern. The combination of the multiple images acquired from the CCD's onto one single image forms a pattern, which is dictated by the predefined arrangement of the CCD's. The size and centroid on the combined image are a direct measure of the depth location Z and in-plane position (X,Y), respectively.

Abstract: A radiation source distribution image of an examinee is formed by driving X direction movement motors to move a radiation information-detecting unit in the X direction, and detecting radiation from the examinee on a stretcher placed between guide rails by using a collimator and a line sensor which constitute a detection unit.

Abstract: After the position of a collimator with respect to a gamma camera depending on the position of a detection plane in an examinee, gamma rays radiated from the examinee are detected by a scintillation detector via a collimator and a scintillator, and a signal from the scintillation detector is processed by a signal processing circuit and then transferred to an image reconstructing unit, which reconstructs a three-dimensional image of the radiation source in the examinee and displays the three-dimensional image on a display unit.

Abstract: Improved systems and methods for coded aperture imaging of radiation-emitting sources. According to one aspect, the present invention is directed to reducing and/or eliminating the artifacts that are inherent in previous near field coded aperture imaging systems such that the improved sensitivity and resolution of these systems can be practically utilized. A system and method of the present invention utilizes two projections of radiation from an object, the first through a first coded aperture mask pattern, and the second through a second coded aperture mask pattern, where a decoding array associated with the second mask pattern is the negative of a decoding array associated with the first mask pattern. Data from both projections is combined to produce a reconstructed object image that is substantially free of near-field artifacts. The present invention additionally relates to further improvements in the sensitivity and spatial resolution of coded aperture imaging applications.

Abstract: An x-ray imaging system according to the present invention comprising a stepped scanning-beam x-ray source and a multi-detector array. The output of the multi-detector array is input to an image reconstruction engine which combines the outputs of the multiple detectors over selected steps of the x-ray beam to generate an x-ray image of the object. A collimating element, preferably in the form of a perforated grid containing an array of apertures, interposed between the x-ray source and an object to be x-rayed. A maneuverable positioner incorporating an x-ray sensitive marker allowing the determination of the precise position coordinates of the maneuverable positioner.

Abstract: A radiation source distribution image of an examinee is formed by driving X direction movement motors to move a radiation information-detecting unit in the X direction, and detecting radiation from the examinee on a stretcher placed between guide rails by using a collimator and a line sensor which constitute a detection unit.

Abstract: After the position of a collimator with respect to a gamma camera depending on the position of a detection plane in an examinee, gamma rays radiated from the examinee are detected by a scintillation detector via a collimator and a scintillator, and a signal from the scintillation detector is processed by a signal processing circuit and then transferred to an image reconstructing unit, which reconstructs a three-dimensional image of the radiation source in the examinee and displays the three-dimensional image on a display unit.

Abstract: A coded aperture is placed in proximity of a patient's body and a 2D coded image is acquired in conventional manner. The basic data-acquisition geometry is similar to that used in various coded-aperture systems. According to one aspect of the invention, additional coded images are acquired with different spacings between the aperture and the detector. Alternatively, additional coded images could be acquired with multiple movable apertures or by varying the location of the aperture relative to a patient. Another aspect of the invention resides in the recognition that presently available computer algorithms can process these multiple coded images in such a way as to estimate the integrals of the 3D object over a set of parallel cylindrical tubes extending through the volume of the target object. Such “tube integrals” can be thought of as the output of an ideal collimator where the sensitivity is confined to a tubular region of constant cross-section.

Abstract: Apparatus for collimating particle emanations, whether photons or material particles, comprises a collimator plate and a motion means. The collimator plate is made of an attenuating material capable of attenuating the particle emanations. The collimator has a plurality of apertures of defined cross-sectional diameter, cross-sectional shape and three-dimensional distribution which restricts the emanations to pass through the plate in a plurality of defined collimated beams. The motion means moves the collimator to enable the plurality of collimated beams to form a defined combined beam having a preselected cross-sectional distribution of flux, when averaged over a specified time. The resolution of the collimator is essentially the cross-sectional diameter of the apertures, which is limited only by technical manufacturing capabilities.

Abstract: A positioner for a scintillation camera detector head is designed for use with a detector head of the type having a center of gravity dependent upon the weight of a removable collimator plate and being supported between a pair of substantially parallel support arms such that the detector head is rotatable relative to the support arms about an axis of rotation passing through the support arms. The positioner includes a pair of rigid detector head links for aligning the center of gravity of the detector head relative to the support arms. Each detector head link includes an arm end rotatably attached to the adjacent support arm by way of an arm axle, and a head end rotatably attached to the detector head by way of a head axle. The positioner also includes a lock for selectively securing the relative positions of the detector head and the detector head links.

Abstract: This invention provides coded aperture imaging apparatus and methods for the detection and imaging of radiation which results from nuclear interrogation of a target object. The apparatus includes: 1) a radiation detector for detecting at least a portion of the radiation emitted by the object in response to nuclear excitation and for producing detection signals responsive to the radiation; 2) a coded aperture disposed between the detector and the object such that emitted radiation is detected by the detector after passage through the coded aperture; and 3) a data processor for characterizing the object based upon the detection signals from the detector and upon the configuration of the coded aperture.

Abstract: A radiation detection device for gamma radiation is disclosed having an array of crystals optically positioned adjacent an optional collimator, the crystals emitting visible light upon illumination by the incident gamma radiation. An array of photodetectors is optically positioned adjacent the crystal array on the side of the crystal array opposite that of the collimator. A select photodetector in the photodetector array provides an output signal when the select photodetector is illuminated by the visible light. An integrated circuit having an input from the output signals of said array of photodetectors is used to process and output signals indicative of the intensity and position of the gamma radiation.

Abstract: An apparatus for analyzing substances within a breast is disclosed. The apparatus includes a breast positioning area and a beam forming apparatus having a geometry which forms breast penetrating radiation into at least one beam. A detector is configured to detect a scattering pattern of the portion of the breast which scatters radiation from the at least one beam when the breast is positioned within the breast positioning area.