Abstract: Some embodiments include methods, and systems of machining using a beam of photons. In some embodiments, a machining method to remove material in a machined region may include reducing transparency of the region to at least a predefined wavelength by irradiating the region with a first beam of photons to induce generation of free electrons in the region; and machining the region with a second beam of photons having the predefined wavelength. Other embodiments are described and claimed.

Abstract: Apparatus for detecting radiation, including a semiconductor which is arranged to interact with photons of the radiation, and a plurality of electrodes which are configured to sense respective charge distributions in response to interactions of the photons with a region of the semiconductor. The apparatus includes circuitry having respective detector circuits coupled to the electrodes to detect the interactions. The circuitry is configured to receive the respective charge distributions from two or more of the electrodes so as to generate respective energy distributions of the photons for each of the two or more electrodes, to compensate for variations in detection characteristics of the respective detector circuits so as to align the respective energy distributions with each other to form aligned distributions, to sum the aligned distributions to generate an overall energy distribution of the photons, and to output a signal indicative of the overall energy distribution.

Abstract: Some embodiments include methods, and systems of machining using a beam of photons. In some embodiments, a machining method to remove material in a machined region may include reducing transparency of the region to at least a predefined wavelength by irradiating the region with a first beam of photons to induce generation of free electrons in the region; and machining the region with a second beam of photons having the predefined wavelength. Other embodiments are described and claimed.

Abstract: A radiation detection camera head having a focal-plane array of pixelated detectors having constant pitch between pixels over the whole of the camera head, while using detector modules having normal production tolerances, and which can nevertheless be readily removed and replaced in the detector array by means of predetermined gaps between adjacent detector modules. The pixels on the side walls of the detector modules have reduced size to maintain constant pitch over the array in spite of production variation between modules. The reduction in sensitivity due to this reduced size is compensated for by the addition of insulated conductive bands on the side walls. The head collimator is such that the septa fall between pixels and between modules, such that head sensitivity is maintained at its optimum value.

Abstract: A readout system, including a data channel for conveying data, and detector units. Each detector unit includes an input which receives a pulse having a magnitude, a storage buffer which stores an indication of the magnitude, and output circuitry which outputs a request-to-read signal in response to the storage unit receiving the pulse. The units output the indications to the data channel upon receiving a select signal in response to the request-to-read signal. The system includes a processor, which receives the request-to-read signal, and in response transmits the select signal and reads the indication from the data channel. The system also includes selectors, coupled as a tree of hierarchical rows having decreasing numbers of selectors, which convey the request-to-read signals from the detector units to the processor. The selectors also convey the select signals from the processor to the detector units, thereby causing the processor to read the indications.

Abstract: Apparatus for detecting radiation, including a semiconductor which is arranged to interact with photons of the radiation, and a plurality of electrodes which are configured to sense respective charge distributions in response to interactions of the photons with a region of the semiconductor. The apparatus includes circuitry having respective detector circuits coupled to the electrodes to detect the interactions. The circuitry is configured to receive the respective charge distributions from two or more of the electrodes so as to generate respective energy distributions of the photons for each of the two or more electrodes, to compensate for variations in detection characteristics of the respective detector circuits so as to align the respective energy distributions with each other to form aligned distributions, to sum the aligned distributions to generate an overall energy distribution of the photons, and to output a signal indicative of the overall energy distribution.

Abstract: A readout system, including a data channel for conveying data, and detector units. Each detector unit includes an input which receives a pulse having a magnitude, a storage buffer which stores an indication of the magnitude, and output circuitry which outputs a request-to-read signal in response to the storage unit receiving the pulse. The units output the indications to the data channel upon receiving a select signal in response to the request-to-read signal. The system includes a processor, which receives the request-to-read signal, and in response transmits the select signal and reads the indication from the data channel. The system also includes selectors, coupled as a tree of hierarchical rows having decreasing numbers of selectors, which convey the request-to-read signals from the detector units to the processor. The selectors also convey the select signals from the processor to the detector units, thereby causing the processor to read the indications.

Abstract: A pixelated detector assembly comprising a stack of thin detector crystals, each detector crystal having a pair of planar surfaces bound by edges substantially thinner than the dimensions of the surfaces. The stack is disposed such that the radiation to be detected is incident on one set of edges of the stack of detector crystals. The dimension of the planar surfaces in the general direction of incidence of the radiation incidence is sufficient to ensure that substantially all of the high energy photons to be detected are absorbed within the depth of the detector assembly. Each of the detector crystals has a two-dimensional pixelated anode array formed on one of its planar surfaces. A cathode is formed on its opposite planar surface, preferably covering substantially all of the surface.

Abstract: A pixelated detector assembly comprising a stack of thin detector crystals, each detector crystal having a pair of planar surfaces bound by edges substantially thinner than the dimensions of the surfaces. The stack is disposed such that the radiation to be detected is incident on one set of edges of the stack of detector crystals. The dimension of the planar surfaces in the general direction of incidence of the radiation incidence is sufficient to ensure that substantially all of the high energy photons to be detected are absorbed within the depth of the detector assembly. Each of the detector crystals has a two-dimensional pixelated anode array formed on one of its planar surfaces. A cathode is formed on its opposite planar surface, preferably covering substantially all of the surface.

Abstract: A pixelated detector assembly comprising a stack of thin detector crystals, each detector crystal having a pair of planar surfaces bound by edges substantially thinner than the dimensions of the surfaces. The stack is disposed such that the radiation to be detected is incident on one set of edges of the stack of detector crystals. The dimension of the planar surfaces in the general direction of incidence of the radiation incidence is sufficient to ensure that substantially all of the high energy photons to be detected are absorbed within the depth of the detector assembly. Each of the detector crystals has a two-dimensional pixelated anode array formed on one of its planar surfaces. A cathode is formed on its opposite planar surface, preferably covering substantially all of the surface.

Abstract: A radiation detection camera head having a focal-plane array of pixelated detectors having constant pitch between pixels over the whole of the camera head, while using detector modules having normal production tolerances, and which can nevertheless be readily removed and replaced in the detector array by means of predetermined gaps between adjacent detector modules. The pixels on the side walls of the detector modules have reduced size to maintain constant pitch over the array in spite of production variation between modules. The reduction in sensitivity due to this reduced size is compensated for by the addition of insulated conductive bands on the side walls. The head collimator is such that the septa fall between pixels and between modules, such that head sensitivity is maintained at its optimum value.

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: A pixelated detector assembly comprising a stack of thin detector crystals, each detector crystal having a pair of planar surfaces bound by edges substantially thinner than the dimensions of the surfaces. The stack is disposed such that the radiation to be detected is incident on one set of edges of the stack of detector crystals. The dimension of the planar surfaces in the general direction of incidence of the radiation incidence is sufficient to ensure that substantially all of the high energy photons to be detected are absorbed within the depth of the detector assembly. Each of the detector crystals has a two-dimensional pixelated anode array formed on one of its planar surfaces. A cathode is formed on its opposite planar surface, preferably covering substantially all of the surface.

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: 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 detector including a substrate formed of a semiconductor material and defining two opposite facing surfaces and at least one side wall, electrodes formed on two opposite facing surfaces of the substrate, the electrodes on one of the two opposite facing surfaces including an array of mutually spaced pixellated anodes defining interstices therebetween, an electrical insulator formed on the substrate at locations in the interstices between the mutually spaced pixellated anodes, or on the side wall, or both, and an electrical conductor formed onto at least part of the electrical insulator. There is also disclosed a method for overcoming performance degradation in a semiconductor detector due to non-uniformities in an electric field.

Abstract: A method for determining X-ray, or gamma ray photon energy by, irradiating a high resistance n-type or p-type cadmium telluride alloy crystal with X-ray or gamma ray photons respectively providing first and second electrical contacts which are in electrical communication with the crystal, which are respectively negatively and positively biased and which provide free flow of electrons from the negatively biased contact to the crystal, and wherein holes, generated by absorption of photons in the crystal, recombine with the electrons, and determining the photon energy by measuring the amount of charge generated per photon absorbed be the crystal.

Abstract: A semiconductive detector includes a semiconductor substrate having electrodes formed at two opposite-facing surfaces thereof. A peripheral side-wall extends between the two opposite facing-surfaces, and an electrical insulator is formed on at least a portion of the side wall. An electrical conductor is provided over the insulator. A bias voltage may be applied to the conductor such that the electrical insulator and the conductor operate generally in a manner of a field effect transistor.

Abstract: A gamma ray imaging system for providing high resolution images includes a collimator plate with an array of multiple holes which image a gamma emitting object onto a semiconductor gamma detector pixel array coupled to a signal processor. The collimator holes are smaller than half the pixel pitch. The detector array is moved in steps, with a step-size equal to the pitch of the collimator holes, to successive imaging positions. The hole locations and imaging positions are such that gamma photons do not fall on the dead areas of the pixels. An electronic processing unit constructs from the pixel signals produced at each imaging position, a set of independent equations and solves them to derive the exact image signal of each irradiated area, and uses this data to compose and a display a high resolution gamma image of the object.