Patent classifications
G01T1/29
High resolution dynamic detector for imaging and dosimetry in megavoltage radiation therapy
Disclosed herein are variations of megavoltage (MV) detectors that may be used for acquiring high resolution dynamic images and dose measurements in patients. One variation of a MV detector comprises a scintillating optical fiber plate, a photodiode array configured to receive light data from the optical fibers, and readout electronics. In some variations, the scintillating optical fiber plate comprises one or more fibers that are focused to the radiation source. The diameters of the fibers may be smaller than the pixels of the photodiode array. In some variations, the fiber diameter is on the order of about 2 to about 100 times smaller than the width of a photodiode array pixel, e.g., about 20 times smaller. Also disclosed herein are methods of manufacturing a focused scintillating fiber optic plate.
System and method for imaging by gamma radiation detection
A system and method for imaging by gamma radiation detection having at least one processing unit analyzing at least one signal provided by at least one set of detection modules mounted on a frame and including, on the one hand, at least one module of Compton camera type having a field of view directed towards a volume delimited by the frame and, on the other hand, at least one pair of coincidence detection PET modules, diametrically opposite to each other on the frame and defining an imaging axis, the processing unit analyzing the signal derived from the Compton-type module to determine the intersection of the imaging axis with the field of view and to determine the optimal orientations and/or locations of the various detection modules on the frame so that the imaging axis passes through the source of the gamma radiation in the object to be imaged.
System and method for imaging by gamma radiation detection
A system and method for imaging by gamma radiation detection having at least one processing unit analyzing at least one signal provided by at least one set of detection modules mounted on a frame and including, on the one hand, at least one module of Compton camera type having a field of view directed towards a volume delimited by the frame and, on the other hand, at least one pair of coincidence detection PET modules, diametrically opposite to each other on the frame and defining an imaging axis, the processing unit analyzing the signal derived from the Compton-type module to determine the intersection of the imaging axis with the field of view and to determine the optimal orientations and/or locations of the various detection modules on the frame so that the imaging axis passes through the source of the gamma radiation in the object to be imaged.
Compton camera with segmented detection modules
A Compton camera for medical imaging is divided into segments with each segment including part of the scatter detector, part of the catcher detector, and part of the electronics. The different segments may be positioned together to form the Compton camera arcing around part of the patient space. By using segments, any number of segments may be used to fit with a multi-modality imaging system.
Compton camera with segmented detection modules
A Compton camera for medical imaging is divided into segments with each segment including part of the scatter detector, part of the catcher detector, and part of the electronics. The different segments may be positioned together to form the Compton camera arcing around part of the patient space. By using segments, any number of segments may be used to fit with a multi-modality imaging system.
Coded-mask-based X-ray phase-contrast and dark-field imaging
Phase contrast and dark-field X-ray imaging enable imaging of objects that absorb or reflect very little X-ray light. Disclosed is a method and systems for performing coded-mask-based multi-contrast imaging (CMMI). The method includes providing radiation to a coded mask that has a known phase and absorption profile according to a pre-determined pattern. The radiation is then impingent upon a sample, and the radiation is detected to perform phase-reconstruction and image processing. The method and associated systems allow for the use of maximum-likelihood and machine learning methods for reconstruction images of the sample from the detected radiation.
METHOD FOR FORMING A GAMMA IMAGE WITH SUB-PIXEL RESOLUTION, TAKING INTO ACCOUNT A SPATIAL NON-UNIFORMITY IN SENSITIVITY
A method for determining a spatial-sensitivity function of a gamma camera, the gamma camera observing a field of observation (Ω) liable to contain radiation sources, the gamma camera including a detector material; pixels, distributed over a detecting area, each pixel being configured to form a detection signal under the effect of detection of an interaction of an ionising photon in the detector material; a unit for achieving sub-pixel resolution, the unit being programmed to assign a position (x, y) to each detected interaction on the basis of detection signals formed by a plurality of pixels, the position being determined on a mesh dividing each pixel into a plurality of virtual pixels. The method includes steps allowing weights assigned to each virtual pixel to be determined, each weight corresponding to a sensitivity of each virtual pixel.
Compressive imaging method and system comprising a detector, a mask, and a drive for rotating the mask about at least one of one or more axes of rotational symmetry
A mask for use in compressed sensing of incoming radiation includes a material that modulates an intensity of incoming radiation, a plurality of mask aperture regions, and one or more axes of rotational symmetry with respect to the mask aperture regions. Each mask aperture region includes at least one mask aperture that allows a higher transmission of the incoming radiation relative to other portions of the mask aperture region. The relative transmission sufficient to allow a reconstruction of compressed sensing measurements and has a shape that provides a symmetry under rotation about the one or more axes of rotational symmetry. A mutual coherence of a sensing matrix generated by a rotation of the plurality of mask aperture regions is less than one. An imaging system for compressed sensing of incoming radiation including such a mask is also provided.
Systems and methods for determining at least one artifact calibration coefficient
A method for determining at least one artifact calibration coefficient is provided. The method may include obtaining preliminary projection values of a first object. The radiation rays may be detected by at least one radiation detector. The method may further include generating a preliminary image of the first object based on the preliminary projection values of the first object and generating calibrated projection values of the first object based on the preliminary image. The method may further include determining a relationship between the preliminary projection values and the calibrated projection values. The method may further include, for each of the at least one radiation detector, determining a location of the radiation detector and determining an artifact calibration coefficient corresponding to the radiation detector based on the relationship between the preliminary projection values and the calibrated projection values and the location of the radiation detector.
Segmented multi-channel, backside illuminated, solid state detector with a through-hole for detecting secondary and backscattered electrons
A segmented detector device with backside illumination. The detector is able to collect and differentiate between secondary electrons and backscatter electrons. The detector includes a through-hole for passage of a primary electron beam. After hitting a sample, the reflected secondary and backscatter electrons are collected via a vertical structure having a P+/P−/N+ or an N+/N−/P+ composition for full depletion through the thickness of the device. The active area of the device is segmented using field isolation insulators located on the front side of the device.