Abstract: A system for improving the resolution of nuclear medicine gamma cameras. A pixellated crystal scintillator is optically connected to position sensitive photomultiplier tubes. Photons incident on the crystal scintillator travel a distance through the crystal that is directly proportional to the energy level of the photon before converting to photoelectrons. The system uses this depth of interaction information to classify the received photons according to their energy levels. Images may then be displayed using information from only those photons that are within the selected energy class.

Abstract: A technique is provided for increasing the pixel pitch without increasing the interconnect density of a digital detector. Generally, a digital detector has an array of rows and columns of pixels, read out electronics and scan electronics, that are configured to generate and transmit signals based upon radiation impacting the detector. The detector also having a plurality of scan lines, which are coupled to the plurality of rows of pixels. The present technique also provides a multiplexing circuit for selectively coupling the rows of pixels to the respective scan lines for read out of the signals.

Abstract: Apparatus for X-ray analysis of a sample includes an X-ray source, which irradiates the sample, and an X-ray detector device, which receives X-rays from the sample responsive to the irradiation. The device includes an array of radiation-sensitive detectors, which generate electrical signals responsive to radiation photons incident thereon. Processing circuitry of the device includes a plurality of signal processing channels, each coupled to process the signals from a respective one of the detectors so as to generate an output dependent upon a rate of incidence of the photons on the respective detector and upon a distribution of the energy of the incident photons.

Abstract: A semiconductor coincidence detector device including at least a first and a second detector crystal array, each having a first and second surface, an array of pixellated anodes formed on each of the first surfaces, an array of segmented cathodes formed on each of the second surfaces, essentially each of the pixellated anodes being connected to an anode electronic channel for generating a first electrical signal corresponding to the energy of a photon impinging in the semiconductor, and essentially each of the segmented cathodes being connected to a cathode electronic channel for generating an electrical coincidence trigger signal on detection of a photon impinging in the semiconductor, the first electrical signal being read only from anodes located opposite the cathode segment generating the trigger signal.

Abstract: An x-ray imager and method of fabricating an x-ray imager that provides protection to the sensor arrays and the barrier layer from the corrosive effects of the scintillating material. The x-ray imager includes a benzo-cyclo-butene layer between the barrier layer and the scintillating material. The benzo-cyclo-butene layer provides several advantages including low cost and application by spin coating or spray coating.

Abstract: Apparatus for X-ray analysis of a sample includes an X-ray source, which irradiates the sample, and an X-ray detector device, which receives X-rays from the sample responsive to the irradiation. The device includes an array of radiation-sensitive detectors, which generate electrical signals responsive to radiation photons incident thereon. Processing circuitry of the device includes a plurality of signal processing channels, each coupled to process the signals from a respective one of the detectors so as to generate an output dependent upon a rate of incidence of the photons on the respective detector and upon a distribution of the energy of the incident photons.

Abstract: A novel semiconductor detector device, consisting of several layers of two dimensional detector modules each module being divided into an array of separate detector cells by means of the pixelation of the electrodes on the surfaces of the modules. The superimposed detector cells in equivalent positions in each layer are in electrical contact with those in the two immediately adjacent layers, such that the whole device effectively becomes a two dimensional array of stacks of individual detector cells, with a common bottom electrode. Current in each detector cell stack, induced by the absorption of a high energy photon in that stack, is measured by means of an integrating charge sensitive amplifier attached to each anode at the top of each cell stack.

Abstract: A semiconductor radiation detector has a plurality of semiconductor cells for detecting radiation from a subject. These semiconductor cells include a plurality of voltage application electrodes and a plurality of signal read electrodes. The semiconductor cells are so arrayed that the cell array forms a concave shape and the semiconductor cells are parallel to each other. Since the semiconductor cells are arrayed to form a concave shape, not only semiconductor cells near the center but also semiconductor cells near the peripheries are located close to the subject. This increases the positional resolution and sensitivity. Since the semiconductor cells are arranged parallel to each other, collimated gamma rays always perpendicularly enter the incidence surface regardless of the incident position of the gamma rays. This equalizes the distances the gamma rays travel regardless of the incident positions, so the sensitivity is substantially constant regardless of the incident positions.

Abstract: A method of transferring a sample to and from a treating chamber kept in a vacuum atmosphere through a pressure regulatively preparatory chamber. The sample is contained in the sample transfer container, which is kept air-permeable by a dust filtering filter, in a cleaned atmosphere before the sample is transferred to the treating chamber. The sample transfer container is transferred into the preparatory chamber, and the inside of the preparatory chamber is evacuated to a vacuum atmosphere. The sample is then extracted from the sample transfer container in the vacuum atmosphere and is transferred into the treating chamber. Also disclosed is an apparatus for supporting the sample transferring method.

Abstract: A gamma camera head including: a plurality of signal sources, each associated with a pixel position, the source producing a signal when a gamma ray absorption event occurs at or sufficiently close to its associated pixel, wherein the plurality of signal sources is associated with a contiguous extent of pixels; and a plurality of electronic circuits, each of which receives signals from at least two of the plurality of signal sources, wherein each circuit receives the signals only from sources associated with non-contiguous pixels.

Abstract: A lock in pinned photodiode photodetector includes a plurality of output ports which are sequentially enabled. Each time when the output port is enabled is considered to be a different bin of time. A specified pattern is sent, and the output bins are investigated to look for that pattern. The time when the pattern is received indicates the time of flight.

Abstract: A semiconductor radiation detector has a plurality of semiconductor cells arrayed in a matrix parallel to the X-Y plane. A plurality of common electrodes for applying an operating voltage to the semiconductor cells are arranged perpendicularly to the X-Y plane. A plurality of signal electrodes for reading out signals from the semiconductor cells are arranged perpendicularly to the X-Y plane. According to a feature of this invention, each common electrode is shared by a pair of semiconductor cells adjacent in the X direction, and each signal electrode is shared by a pair of semiconductor cells adjacent in the X direction. With this arrangement, the dead zone can be reduced to increase the pixel density, in other words, the spatial resolution. If the pixel density is kept unchanged, the sensible zone of the semiconductor cell can be widened to increase the detection sensitivity.

Abstract: A method and apparatus are provided for the position sensitive detection of radioactivity in a fluid stream, particularly in the effluent fluid stream from a gas or liquid chromatographic instrument. The invention represents a significant advance in efficiency and cost reduction compared with current efforts.

Abstract: A system for measuring gamma-ray radial energy deposition is provided for use in conjunction with a semiconductor detector. The detector comprises two electrodes and a detector material, and defines a plurality of zones within the detecting material in parallel with the two electrodes. The detector produces a charge signal E(t) when a gamma-ray interacts with the detector. Digitizing means are provided for converting the charge signal E(t) into a digitized signal. A computational means receives the digitized signal and calculates in which of the plurality of zones the gamma-ray deposited energy when interacting with the detector. The computational means produces an output indicating the amount of energy deposited by the gamma-ray in each of the plurality of zones.

Abstract: This is a method of generating a plurality of images of a substrate from radioactive radiation coming from a plurality of radioactive tracers contained in the substrate. To this end, data representing the different detection signals generated by a detector are memorised, individually for each radioactive emission detected during a certain observation period, then statistical processing of these data is carried out in such a way as to estimate the images of the different tracers which correspond best to the set of memorised data.

Abstract: A photoconductive detector (3) comprises a single continuous photoconductive strip consisting of two interleaved photoconductive spiral paths (1, 2) separated by much thinner gaps (5, 6). The two spiral paths (1, 2) have the same central point (19). The detector (3) is substantially planar and has the overall shape of roughly a circle (10). A circular band (4) of incident radiation (16) crosses the gaps (5, 6) in a nearly parallel fashion, rather than nearly perpendicularly as in the prior art, lessening unwanted modulations of the detected signal. The terminal (11) to terminal (12) resistance of the detector (3) is increased to the point where, when the photodetector (3) is made of the preferred HgCdTe, simple thermo-electric coolers are sufficient to enable use of the detector (3) as an infrared detector (3) in a heat-seeking missile (17).

Abstract: A method for obtaining both spatial and energy resolution in compound semiconductor x-ray detectors using charge carriers of only a single polarity. A negatively biased cathode contact is applied to one side of a block detector material and an array of anode stripes is applied to the other side. Absorbed x-rays generate charge clouds in the detector block, and charge sensitive preamplifiers measure the time varying charges qi(t) induced on the anodes by the motion of these charge clouds within the detector. For each stripe j, one or more secondary signals Qk,m(t) are formed as weighted sums of the signals qk(t) from the stripe j and a combination of its near neighbors. One or another of these signals Qk,m(t) can then be processed to obtain the energy of the absorbed x-ray, the position where it was absorbed, both laterally and in depth, and the time of the absorption.