Abstract: Systems, methods, and devices for thermally protecting a scintillator crystal of a scintillation detector are provided. In one example, a thermally-protected scintillator may include a scintillator crystal and a thermal protection element, which may partially surround the scintillator crystal. The thermal protection element may be configured to prevent the scintillator crystal from experiencing a rate of change in temperature sufficient to cause cracking or non-uniform light output, or a combination thereof.

Abstract: A microdosimeter, comprising an array of three-dimensional p-n junction semiconductor detectors, each providing a sensitive volume-target and a tissue equivalent medium for generating secondary charged particles. The array is manufactured from a semiconductor on insulator wafer and the detectors are located to detect secondary charged particles generated in the tissue equivalent medium.

Abstract: Method, apparatus and system for reducing or preventing polarization in semiconductor radiation detectors for medical imaging. For example, an apparatus includes a semiconductor with electrodes coupled thereto, configured to generate an electrical signal in the electrodes in response to absorption of ionizing radiation in the semiconductor, wherein the absorption of the ionizing radiation generates a space charge in the semiconductor; and an infra-red (IR) generator configured to generate IR radiation of a selectable wavelength, the selectable wavelength being chosen so as to at least partially reduce an effect of the space charge on the electrical signal.

Abstract: A high speed and miniature detection system, especially for electromagnetic radiation in the GHz and THz range comprises a semiconductor structure having a 2D charge carrier layer or a quasi 2D charge carrier layer with incorporated single or multiple defects, at least first and second contacts to the charge carrier layer, and a device for measuring photovoltage between the first and second contacts. System operation in various embodiments relies on resonant excitation of plasma waves in the semiconductor structure.

Abstract: A method of detecting radiation through which the residence time of charge carriers is dramatically reduced by an external optical energy source and the occupancy of the deep-level defects is maintained close to the thermal equilibrium of the un-irradiated device even under high-flux exposure conditions. Instead of relying on thermal energy to release the trapped carriers, infra-red light radiation is used to provide sufficient energy for the trapped carriers to escape from defect levels. Cd1-xZnxTe crystals are transparent to infra-red light of this energy and no additional absorption occurs other than the one associated with the ionization of the targeted deep-level defects. This allows irradiation geometry from the side source of the Cd1-xZnxTe detector crystals.

Abstract: The present invention discloses an apparatus for use in medical imaging including a readout circuit having an input for receiving a detection signal corresponding to a photon hitting a radiation detector, wherein the readout circuit is adapted to output, in response to receiving said detection signal, a pulse signal having a leading edge encoding a time-stamp of said photon and a width encoding the energy of said photon. A method of reading out detection signals from a radiation detector of a medical imaging apparatus is also provided.

Abstract: A method for imaging a radiation source, and a device that utilizes these methods that in one embodiment include the steps of: calculating at least one Compton cone of a first parameter of a radiation emission from information received from a sensor occurrence; and tracing this Compton cone on to a unit sphere having preselected characteristics using an estimated angular uncertainty to limit at least a portion of said tracing. In another embodiment of the invention at least two Compton cones are calculated and then intersected upon a predefined surface such as a sphere. These intersection points can then be iterated over a preselected series of prior events.

Abstract: If image data is input to an image processor (step S1), the image processor generates an integrated image sum (step S2). The image processor extracts a maximum output max from the integrated image sum (step S3). The image processor compares the maximum output max with a preset threshold (step S4). In this case, the threshold is set to 80% of the saturation amount. When the saturation amount is 3 V, the threshold is 2.4 V. If the maximum value max is smaller than the threshold, imaging continues. If the maximum value max is equal to or larger than the threshold, the integrated image sum is cleared to 0 (step S5), and refresh operation is performed.

Abstract: Nested ionization chambers provide independent measurements of a radiation beam that does not fully irradiate the volume of one or both chambers. By mathematically combining these independent measurements, partial volume effects caused by a change in ionization detector calibrations when the full detector volume is not irradiated by the radiation beam, may be decreased, providing more accurate measurement of extremely small radiation beams.

Abstract: An imaging system for imaging an object has an x-ray source for emitting x-rays. A detection system has a plurality of position sensitive detector planes, and the object is located between the x-ray source and the detection system. A portion of the x-rays pass through said object and pass into said plurality of detector planes and are detected within the plurality of detector planes. A multi-channel readout system is coupled to the plurality of position sensitive detector planes. A display system is coupled to the multi-channel readout system, and the display system displays an image of said object. A portion of the x-rays passing into the plurality of detector planes undergoes at least one Compton scatter within the plurality of detection planes and is detected. A total or partial energy corresponding to each portion of the emitted x-rays is recorded by a multichannel readout system.

Abstract: A conversion apparatus includes pixels including switching elements provided on an insulating substrate and conversion elements disposed over the switching elements and connected to the switching elements. Conductive lines are coupled to the pixels and have terminal elements for providing a connection to an external circuit. The terminal elements are disposed in a metal layer that is formed over the conversion elements. The conversion apparatus further includes a transparent conductive layer covering surfaces of the terminal elements, and a protective layer covering edges of the terminal elements and having openings.

Abstract: A radiation detector includes at least one multiple channel pixellated detector driven via a plurality of pixellated anode electrodes and at least one planar cathode electrode. Each detector is configured to reduce the number of active pixellated anode electrodes until a rate of events detected via at least one corresponding planar cathode electrode exceeds a preset threshold above a background count rate within a predetermined time period.

Abstract: A detector assembly for detecting radiation with angular resolution comprises at least one detector element, which comprises a front face and a rear face, a first detector material and a second detector material between the front face and the rear face, a space between the front face and the rear face of the detector element being filled by a plurality of regions of the first detector material and at least one region of the second detector material and each region connecting the front face to the rear face of the detector element; and radiation incident on the detector element through the front face being collimated by means of the detector materials.

Abstract: Improved position estimation for a square photodetector having terminals at its corners is provided by first estimating an event position in a coordinate system aligned with the diagonals of the square, and then performing a coordinate rotation to provide an estimated position in a coordinate system aligned with the sides of the square. These two steps can also be mathematically combined. It is believed that the improved accuracy of this position determination approach is a result of a greater degree of linearity in charge division between terminals along diagonal axes than along orthogonal axes of a square detector. Flood images provided by this method have been compared to flood images provided by the conventional Anger method, and substantially less image distortion is observed with the present method than with the Anger method.

Abstract: As a radiation imaging apparatus which can easily and effectively correct line noise, there is provided a radiation imaging apparatus having: a conversion unit having a pixel region in which a plurality of pixels each having a conversion element (202) for converting radiation into an electric charge and a switching element (201) for outputting an electric signal based on the electric charge are arranged in a matrix; a capacitor element (301) arranged outside the pixel region; a reading out circuit unit (108) for reading out the electric signals from the pixels row by row and reading out, in parallel, a signal from the capacitor element and the electric signal from the pixel; and a correction unit for correcting the electric signal based on the signal from the capacitor element.

Abstract: A detector unit (301) for detecting electromagnetic radiation (106), the detector unit (301) comprising a conversion material (332) adapted for converting impinging electromagnetic radiation (106) into electric charge carriers, a charge collection electrode (331) adapted for collecting the converted electric charge carriers, a shielding electrode (334, 335) adapted to form a capacitance with the charge collection electrode (331), and an evaluation circuit (312 to 315) electrically coupled with the charge collection electrode (331) and adapted for evaluating the electromagnetic radiation (106) based on the collected electric charge carriers.

Abstract: A radiation detection blanket for use in surveying a broad or irregular area of interest for radiation emissions. Small radiation detectors are affixed to the fabric and distributed relative to its surface area. The detector materials may be of the OSL, TLD, or ERD variety, or may be a combination of OSL, TLD and ERD. Detector materials having varying thicknesses of high Z coatings may be clustered together in the blanket fabric to yield a gamma radiation spectrum. Use of a converter material on the detector material allows the blanket to detect neutron radiation. The blanket includes specialized transmission means for allowing the detector materials to be read individually, by passing the reader along a surface or along an edge of the blanket. A composite radiation measurement is obtained upon reading the individual detectors, allowing determination of the radiation distribution within the object being surveyed by the blanket.

Abstract: This invention describes an imaging system based on an array of semiconductor photosensitive elements with isolating structure between elements (pixels) of the array. The isolated pixels of the array may be photodiodes and they provide excellent imaging capabilities that are important for many applications. The isolated photosensitive pixels may be comprised also by photoconductors, avalanche photodiodes, photosensitive IC, or other similar solid-state devices. The fields of possible application include but are not limited to the detector modules for homeland security, medical imaging systems (CT, SPECT, and PET including), fundamental and applied research, etc.

Abstract: A micro-fluidic device has a micro-fluidic circuit layer and a charged-particle detection layer disposed proximate the micro-fluidic circuit layer. The micro-fluidic device is constructed to provide a two-dimensional image of charged-particle emissions from a sample within the micro-fluidic circuit layer while in operation. A method of quantification of radioactivity in a biological sample includes directing a fluid containing the biological material into a microfluidic device, detecting charged particles emitted from the biological material with a two-dimensional imaging sensor, and forming a two-dimensional image over time corresponding to radioactivity of the biological sample.

Abstract: A solid-state detector for detection of neutron and alpha particles detector and methods for manufacturing and use thereof are described. The detector has an active region formed of a polycrystalline semiconductor compound comprising a particulate semiconductor material sensitive to neutron and alpha particles radiation imbedded in a binder. The particulate semiconductor material contains at least one element sensitive to neutron and alpha particles radiation, selected from a group including 10Boron, 6Lithium, 113Cadmium, 157Gadolinium and 199Mercury. The semiconductor compound is sandwiched between an electrode assembly configured to detect the neutron and alpha particles interacting with the bulk of the active region. The binder can be either an organic polymer binder or inorganic binder. The organic polymer binder comprises at least one polymer that can be selected from the group comprising polystyrene, polypropylene, Humiseal™ and Nylon-6.

Abstract: An apparatus for detecting radiation includes a dual-speed scintillator for receiving the radiation and emitting secondary radiation in response thereto, and detectors in communication with the dual-speed scintillator for receiving the secondary radiation.

Abstract: A dosimeter comprising an ionizing radiation detector array is used to generally encompass a three dimensional geometric shape such as that employed as a phantom in radiation dosimetry measurements. The ionizing radiation detector array may include passive or active detectors. The active detectors in the array may comprise diodes, ionization chambers, luminescent sensors or amorphous silicon. The three dimensional geometric shape may comprise a shape defined by a closed directrix, wherein each of a plurality of detectors within the ionizing detector array is within an envelope defined by a generatrix of the directrix. The closed directrix may be an open or closed cylinder, or a structure having a cross section described by a polygon. The plurality of detectors may only be positioned on or at least proximate the envelope.

Abstract: An improved diode sensor for calibration of megavoltage radiation machines eliminates high atomic number metallic components adjacent to a bottom surface of the diode substrate (away from the depletion region) to decrease a sensitivity of the diode sensor to incident angle of the radiation.

Abstract: A radiation dosimetry apparatus and method use a scintillating optical fiber array for detecting dose levels. The scintillating optical fiber detectors generate optical energy in response to a predetermined type of radiation, and are coupled to collection optical fibers that transmit the optical energy to a photo-detector for conversion to an electrical signal. The detectors may be embedded in one or more modular, water-equivalent phantom slabs. A repeatable connector couples the collection fibers to the photo-detector, maintaining the fiber ends in a predetermined spatial relationship. The detector fibers may be distributed as desired in a three-dimensional detection space, and may be oriented with their longitudinal axes at different orientations relative to a transmission axis of an incident radiation beam. A calibration method uses two measurements in two spectral windows, one with irradiation of the scintillator at a known dose and one with only irradiation of the collection fiber.

Abstract: Generation of residual images due to charge leakage is suppressed. A radiation image detector is constituted by: an upper planar electrode that transmits electromagnetic waves bearing radiation image information; a charge generating layer that generates electric charges when irradiated by the electromagnetic waves which are transmitted through the upper planar electrode; and a plurality of divided electrodes for collecting the electric charges generated by the charge generating layer. The divided electrodes have inclined electrode surfaces, which are inclined with respect to the upper planar electrode.

Abstract: High rate radiation detectors are disclosed herein. The detectors include a detector material disposed inside the container, the detector material containing cadmium, tellurium, and zinc, a first dopant containing at least one of aluminum, chlorine, and indium, and a second dopant containing a rare earth metal. The first dopant has a concentration of about 500 to about 20,000 atomic parts per billion, and the second dopant has a concentration of about 200 to about 20,000 atomic parts per billion.

Abstract: Interaction depth of photons in a CdZnTe pixel detector is measured by configuring an ASIC connected to the detector to measure both positive polarity and negative polarity signal amplitudes and then measuring a core pixel having positive signal amplitude and hallow pixels having negative signal amplitude and surrounding the core pixel.

Abstract: A solid-state imaging device, such as a CMOS sensor, includes a unit pixel having a charge generation unit for generating signal charge, a floating diffusion for accumulating the signal charge generated by the charge generation unit, a transfer gate transistor for transferring the signal charge in the charge generation unit to the floating diffusion, a reset transistor for resetting the floating diffusion, and an amplifying transistor for generating a signal in accordance with the signal charge generated by the charge generation unit and outputting the signal to a vertical signal line. The width of a reset pulse for driving the reset transistor is sufficiently decreased to, for example, less than or equal to ½, and preferably less than or equal to ? of the response time of a signal that has occurred on the vertical signal line in response to the reset pulse.

Abstract: A wiring substrate section 2 is provided between a radiation detecting section 1, which is formed of a scintillator 10 and a PD array 15, and signal processing elements 30 and 32 for processing a detected signal outputted from the PD array 15, and the wiring substrate section 2 has a wiring substrate 20 which is formed of a glass material having a radiation shielding function and in which a conductive member 21 serving as a conduction path for guiding the detected signal therethrough is provided in a through hole 20c. Relative to the through hole 20c of the wiring substrate 20, the signal processing elements 30 and 32 of the signal processing section 3, located downstream of the wiring substrate 20, are each disposed in an area excluding those areas on the extension of the through holes 20c, and this allows the signal processing elements 30 and 32 not to be seen through the through holes 20c.

Abstract: A method is described. A total number of traps to be filled in a detector of an imaging system is estimated based on a measured signal sensed by the detector. The measured signal is adjusted based on the estimated total number of traps and a current trap state of the detector. The trap state of the detector is subsequently updated.

Abstract: GaTe semiconductor is used as a room-temperature radiation detector. GaTe has useful properties for radiation detectors: ideal bandgap, favorable mobilities, low melting point (no evaporation), non-hygroscopic nature, and availability of high-purity starting materials. The detector can be used, e.g., for detection of illicit nuclear weapons and radiological dispersed devices at ports of entry, in cities, and off shore and for determination of medical isotopes present in a patient.

Abstract: In a radiation detector, a response is approximated as a primary delay system, and when a time constant T indicating the characteristic of the response is known, a final response value N0 is forecasted from dose rates or counting rates N1 and N2 of two points in the initial or middle stage of response. When the time constant T is unknown, the final response value N0 is forecasted from dose rates or counting rates N1, N2, and N3 of three points in the initial or middle stage of response. Simultaneously, a time constant is obtained and the soundness of the radiation detector is also evaluated. Thereby, a dose rate in an existence field of radiation or a counting rate in an existence field of radioactive materials is quickly and accurately forecasted, whereby the measurement time is shortened.

Abstract: The present invention is directed to an energy dispersive X-ray detector appliance and a method for pulsed reset of said appliance. The present invention provides a ramp-and-neutralize cycled I-FET SDD in which the voltage dependency and nonlinearity due to the integrated FET is reduced via a compensation circuit to a level that can be handled by a correction circuit. The correction circuit does not substantially add noise or other kinds of erroneous signals. Accordingly, the appliance comprises a silicon drift detector with internal field effect transistor I-FET SDD, a compensation circuit for compensating nonlinearities in the I-FET SDD; and a neutralizing circuit adapted to neutralize accumulated charges in I-FET SDD comprising means for pulsed reset of the detector.

Abstract: A radiation detector includes an array of detector pixels each including an array of detector cells. Each detector cell includes a photodiode biased in a breakdown region and digital circuitry coupled with the photodiode and configured to output a first digital value in a quiescent state and a second digital value responsive to photon detection by the photodiode. Digital triggering circuitry is configured to output a trigger signal indicative of a start of an integration time period responsive to a selected number of one or more of the detector cells tranisitioning from the first digital value to the second digital value. Readout digital circuitry accumulates a count of a number of transitions of detector cells of the array of detector cells from the first digital state to the second digital state over the integration time period.

Abstract: Interaction depth of photons in a CdZnTe pixel detector is measured by configuring an ASIC connected to the detector to measure both positive polarity and negative polarity signal amplitudes and then measuring a core pixel having positive signal amplitude and hallow pixels having negative signal amplitude and surrounding the core pixel.

Abstract: In order to increase the useful surface of an X-ray detector, in particular a flat image detector, a method is provided for gain calibration of an X-ray imaging system with a digital X-ray detector including an active matrix having pixel readout units. Pixels are read out from the pixel readout units, and a brightness drop below a defined threshold is determined for the read out pixels by an image processing unit. The pixel readout units having a brightness drop below the defined threshold are specified with regard to a cause of the brightness drop. Further, as a function of the specification, it is defined for which image raw values, subsequently read out from the affected pixel readout units, a gain correction is to be undertaken.

Abstract: A method for exploiting a signal provided by a detector is disclosed. For one embodiment, the time spent by at least one part of the signal above a value S0 of a first threshold is determined. The charge corresponding to the part of the signal during the time spent above the value S0 of the first threshold is determined. A new value S?0 of the first threshold as a function of the charge and the time spent above the value S0 of the first threshold is determined. The steps of determining the time spent by at least one part of the signal above a value S0 of a first threshold and determining the charge corresponding to the part of the signal during the time spent above the value S0 of the first threshold are reiterated at least once using the new value of the first threshold.

Abstract: Method and apparatus for sensing and acquiring radiation data comprises sensing radiation events with a multi-modality detector. The detector comprises solid state crystals forming a matrix of pixels which may be arranged in rows and columns, and has a radiation detection field for sensing radiation events. The radiation events for each pixel are counted by an electronic module attached to each pixel. The electronic module comprises a threshold analyzer for analyzing the radiation events. The threshold analyzer identifies valid events by comparing an energy level associated with the radiation event to a predetermined threshold. The electronic module further comprises at least a first counter for counting the valid events.

Abstract: A method is described. A total number of traps to be filled in a detector of an imaging system is estimated based on a measured signal sensed by the detector. The measured signal is adjusted based on the estimated total number of traps and a current trap state of the detector. The trap state of the detector is subsequently updated.

Abstract: The present invention is an indirect AMFPI wherein a phosphor such as a structured cesium iodide (CsI) is used to convert x-ray energy to optical photons or a charge, which is then detected by a two-dimensional array of either thin-film transistors (TFTs) such as an amorphous a-Se TFTs or a photodiode array. A scanning control circuit generates pulses to turn on the TFTs one row at a time, and thus the charge in the individual arrays is transferred from the TFT to one or more external charge-sensitive amplifiers. The charge-sensitive amplifiers are shared by all the pixels in the same column. The two-dimensional array can be read in real time.

Abstract: A portable, self-contained, electronic radioscopic imaging system uses a pulsed X-ray source, a remote X-ray sensor, and a self-contained, display and controller unit to produce, store, and/or display digital radioscopic images of an object under investigation. The pulsed X-ray source transmits a burst of narrow pulses of X-rays at the object being investigated at a low repetition rate. The X-ray sensor utilizes an X-ray scintillating screen in combination with either an integrating CCD camera, or an active matrix of thin film transistors and sample-and-hold photodiodes, to produce an integrated signal representative of the accumulated number of flashes of radiation that are sensed in a given pixel area of the scintillating screen. The self-contained display and controller unit utilizes digital signal processing within an enhanced portable computer, including a flat solid state display panel and associated drive circuitry, in order to display the full dynamic range and resolution of the sensor.

Abstract: A solid-state imaging device, such as a CMOS sensor, includes a unit pixel having a charge generation unit for generating signal charge, a floating diffusion for accumulating the signal charge generated by the charge generation unit, a transfer gate transistor for transferring the signal charge in the charge generation unit to the floating diffusion, a reset transistor for resetting the floating diffusion, and an amplifying transistor for generating a signal in accordance with the signal charge generated by the charge generation unit and outputting the signal to a vertical signal line. The width of a reset pulse for driving the reset transistor is sufficiently decreased to, for example, less than or equal to ½, and preferably less than or equal to ? of the response time of a signal that has occurred on the vertical signal line in response to the reset pulse.

Abstract: The present invention relates to a method of detecting X-rays for obtaining improved radiographic images including a step of orienting a semiconductor radiation detector whose height is greater than its thickness. The orienting step comprises a selection of an acute angle between a direction of incident radiation and a side of said detector having said height such that said incident radiation mainly hit the side of said radiation detector. The hit area excludes at least a section between at least one edge of said detector and at least an active sensor area and that substantially all of the energy of the radiation is dissipated within the detector.

Abstract: A method for producing a high resolution detector array so as to provide very high packing fraction, i.e. the distance between scintillator elements is minimized so the detector efficiency will be higher than is currently achievable. In the preferred embodiment of the present invention, the fabrication methodology is enhanced by handling LSO bars rather than single crystals when gluing on the Lumirror® as well as etching the LSO. Namely, an LSO boule is cut into wide bars of a selected dimension, for example 30 mm, which are then acid etched or mechanically polished. A selected number, N, of these LSO bars can then be glued together with Lumirror® sheets between each bar (coating the LSO disks and Lumirror® sheets with Epotek 301-2). The glued bar block is then cut again into bars in a perpendicular direction, and these new LSO-Lumirror® bars are etched.

Abstract: Methods are provided for identifying root causes of particle issues and for developing particle-robust process recipes in plasma deposition processes. The presence of in situ particles within the substrate processing system is detected over a period of time that spans multiple distinct processing steps in the recipe. The time dependence of in situ particle levels is determined from these results. Then, the processing steps are correlated with the time dependence to identify relative particle levels with the processing steps. This information provides a direct indication of which steps result in the production of particle contaminants so that those steps may be targeted for modification in the development of particle recipes.

Abstract: A signal readout system for a solid state detector array comprising a plurality of detection channels, wherein the decision to output a signal detected by a channel is determined by the content of that channel.

Abstract: The present invention relates a method of enhancing contrast information from an x-ray detecting arrangement, when detecting a number of photons in said arrangement comprising at least two adjacently arranged sensors provided on one substrate, each sensor having a corresponding output signal, each of which can be influenced due to shared charge from a photon detected in one of said adjacent sensors, which detected photon indirectly creates an amount of free charges proportional to the photon energy, wherein said influence on said signal is considered by weighting said photon with respect to possible said photon charge-share between said at least two adjacent sensors.

Abstract: The present invention relates a method of enhancing contrast information from an x-ray detecting arrangement, when detecting a number of photons in said arrangement comprising at least two adjacently arranged sensors provided on one substrate, each sensor having a corresponding output signal, each of which can be influenced due to shared charge from a photon detected in one of said adjacent sensors, which detected photon indirectly creates an amount of free charges proportional to the photon energy, wherein said influence on said signal is considered by weighting said photon with respect to possible said photon charge-share between said at least two adjacent sensors.

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: The imaging magnification of an imaging optical system 6 is set such that the image resolution of an ultraviolet CCD camera 5 is within a range from 10 nm to 30 nm, on a resist pattern 102 to be inspected. In addition, every time when the ultraviolet CCD camera 5 picks up an image, the resist pattern 102 to be inspected is irradiated at an irradiation light amount within a range from 0.5 mJ/cm2 to an irradiation threshold value at which the resist pattern 102 is not caused to contract or an irradiation threshold value at which an absorption rate of an anti-reflection film provided near the resist pattern is not caused to change.