A scintillation detector, including a scintillator that emits scintillation; a semiconductor photodetector having a surface area for receiving the scintillation, wherein the surface area has a passivation layer configured to provide a peak quantum efficiency greater than 40% for a first component of the scintillation, and the semiconductor photodetector has built in gain through avalanche multiplication; a coating on the surface area, wherein the coating acts as a bandpass filter that transmits light within a range of wavelengths corresponding to the first component of the scintillation and suppresses transmission of light with wavelengths outside said range of wavelengths; and wherein the surface area, the passivation layer, and the coating are controlled to increase the temporal resolution of the semiconductor photodetector.

A collimator for a SPECT system, the collimator being adapted for absorbing and collimating gamma rays emitted by a radiation source within a field of view the collimator, said collimator having an alignment direction for directing along a longitudinal axis of a measuring cavity of the SPECT system and said collimator comprising at least one collimator body of radiation absorbing material, the collimator body comprising a plurality of apertures being formed in the collimator body, the plurality of apertures being arranged in a plurality of groups separated from each other in said alignment direction. The apertures of each group are oriented such as to define at least one projection view along a corresponding at least one projection direction. The plurality of said projection directions corresponding to each and every of said plurality of groups cover an angular range sufficiently large for sufficient image information for artifact-free reconstruction.

A detector for detecting a single x-ray photon with high temporal resolution and high efficiency includes a semiconductor substrate, the semiconductor substrate including element(s) from each of Groups III and V of the Periodic Table of Elements, and pixels on the substrate. Each pixel includes a semiconductor transistor including an epitaxial layer having element(s) from each of Groups III and V of the Periodic Table of Elements, an anode electrically connected to a gate of the semiconductor transistor, and a cathode electrically connected to a drain of the semiconductor transistor. Photon(s) are caused to impinge the single-photon detector along a y-direction (long side of pixel) to provide adequate stopping power, and electron-hole pairs generated by the photon(s) are collected along an x-direction or z-direction (short sides of pixel) to provide short transit time. Detectors form an array of pixels for x-ray imaging with temporal resolution of single photons.

A radiation detector assembly is provided that includes a semiconductor detector having a surface, plural pixelated anodes, and at least one processor. The pixelated anodes are disposed on the surface. Each pixelated anode is configured to generate a primary signal responsive to reception of a photon by the pixelated anode and to generate at least one secondary signal responsive to an induced charge caused by reception of a photon by at least one adjacent anode. The at least one processor is operably coupled to the pixelated anodes. The at least one processor configured to define sub-pixels for each pixelated anode; acquire signals corresponding to acquisition events from the pixelated anodes; determine sub-pixel locations for the acquisition events using the signals; and apply at least one calibration parameter on a per sub-pixel basis for the acquisition events based on the determined sub-pixel locations.

In one embodiment, a method includes forming a powder having a composition with the formula: A.sub.hB.sub.iC.sub.jO.sub.12, where h is 3±l 0%, i is 2=10%, j is 3±10%, A includes one or more rare earth elements, B includes aluminum and/or gallium, and C includes aluminum and/or gallium. The method additionally includes consolidating the powder to form an optically transparent ceramic, and applying at least one thermodynamic process condition during the consolidating to reduce oxygen and/or thermodynamically reversible defects in the ceramic. In another embodiment, a scintillator includes (Gd.sub.3-a-cY.sub.a)x(Ga.sub.5-bAl.sub.b).sub.yO.sub.12D.sub.c, where a is from about 0.05-2, b is from about 1-3, x is from about 2.8-3.2, y is from about 4.8-5.2, c is from about 0.003-0.3, and D is a dopant, and where the scintillator is an optically transparent ceramic scintillator having physical characteristics of being formed from a ceramic powder consolidated in oxidizing atmospheres.

The present invention relates to a detection device (6) for detecting photons emitted by a radiation source (2). The detection device (6) is configured to detect the photons during a first time period. The detection device (6) comprises a sensor (10) having an intermediate direct conversion material for converting photons into electrons and holes, a shaping element (20), and a compensation unit (450, INT, 950). The compensation unit (450, INT, 950) is adapted to provide a compensation signal based on the electrical pulse and on a photoconductive gain of said sensor (10). The core of the invention is to provide circuits to reduce artifacts due to inherent errors with direct conversion detectors in spectral computed tomography by determining a compensation current, by detecting or monitoring a baseline restorer feedback signal, or by ignoring signals above the baseline level.

Various aspects include methods of compensating for issues caused by charge sharing between pixels in pixel radiation detectors. Various aspects may include measuring radiation energy spectra with circuitry capable of registering detection events occurring simultaneous or coincident in two or more pixels, adjusting energy measurements of simultaneous-multi-pixel detection events by a charge sharing correction factor, and determining a corrected energy spectrum by adding the adjusted energy measurements of simultaneous-multi-pixel detection events to energy spectra of detection events occurring in single pixels. Adjusting energy measurements of simultaneous-multi-pixel detection events may include multiplying measured energies of simultaneous-multi-pixel detection events by a factor of one plus the charge sharing correction factor.

A radiation detector according to an embodiment includes a light emitting element, an optical sensor, and a filter. The light emitting element generates light in conjunction with radiation becoming incident thereto. The optical sensor detects the light. The filter is provided between the light emitting element and the optical sensor and passes only a certain wavelength of the light so that delay time until the light is detected becomes shorter.

A radiation detector assembly is provided that includes a semiconductor detector, plural pixelated anodes disposed on a surface of the semiconductor detector, and at least one processor. Each pixelated anode generates a primary signal responsive to reception of a photon by the pixelated anode. The at least one processor is operably coupled to the pixelated anodes, and determines when a primary signal is generated by a given pixelated anode. Responsive to determining the presence of the primary signal in the given pixelated anode, the at least one processor disconnects the given pixelated anode from an electrical source, wherein a re-directed primary signal is directed to a surrounding pixelated anode of the given pixelated anode. The at least one processor identifies the surrounding pixelated anode, and assigns an event for the primary signal to a pre-determined sub-pixel portion of the given pixelated anode based on the identified surrounding pixelated anode.

Among other things, one or more techniques and/or systems are described for setting a sampling frequency for a radiation imaging system. The radiation imaging system comprises a rotating gantry configured to rotate a radiation source and a detector array about an object to generate an image(s) of the object. A data acquisition system is configured to sample the detector array as views. One or more flag structures are arranged according to a partial arc segment (e.g., a structure less than a full 360 degree circle). One or more sensors are disposed on one of the rotating gantry or a stationary support about which the rotating gantry rotates. When a sensor encounters a flag structure, a current rotational speed of the rotating gantry is determined. A clock frequency is updated based upon the current rotational speed to establish a sampling frequency for the data acquisition system for sampling the detector array.