摘要:
The invention relates to a radiation detector that is particularly suited for energy resolved single X-ray photon detection in a CT scanner. In a preferred embodiment, the detector has an array of scintillator elements in which incident X-ray photons are converted into bursts of optical photons. Pixels associated to the scintillator elements determine the numbers of optical photons they receive within predetermined acquisition intervals. These numbers can then be digitally processed to detect single X-ray photons and to determine their energy. The pixels may particularly be realized by avalanche photodiodes with associated digital electronic circuits for data processing.
摘要:
The invention relates to a radiation detector (100) that is particularly suited for energy resolved single X-ray photon detection in a CT scanner. In a preferred embodiment, the detector (100) comprises an array of scintillator elements (S k) in which incident X-ray photons (X) are converted into bursts of optical photons (hn). Pixels (P k) associated to the scintillator elements (S k) determine the numbers of optical photons they receive within predetermined acquisition intervals. These numbers can then be digitally processed to detect single X-ray photons (X) and to determine their energy. The pixels may particularly be realized by avalanche photodiodes with associated digital electronic circuits for data processing.
摘要:
A positron emission tomography apparatus (100) includes a plurality of radiation sensitive detector systems (106) and selective trigger systems (120). The selective trigger systems identify detector signals resulting from detected gamma radiation (310) while disregarding spurious detector signals (310). In one implementation, the apparatus (100) includes a time to digital converter which decomposes a measurement time interval (Tmax) according to a binary hierarchical decomposition of level H, where H is an integer greater than equal to one.
摘要:
A positron emission tomography apparatus (100) includes a plurality of radiation sensitive detector systems (106) and selective trigger systems (120). The selective trigger systems identify detector signals resulting from detected gamma radiation (310) while disregarding spurious detector signals (310). In one implementation, the apparatus (100) includes a time to digital converter which decomposes a measurement time interval (Tmax) according to a binary hierarchical decomposition of level H, where H is an integer greater than equal to one.
摘要:
A diagnostic imaging device includes a signal processing circuit (22) processes signals from a detector array (16) which detects radiation from an imaging region (20). The hit signals are indicative of a corresponding detector (18) being hit by a radiation photon. The signal processing circuit (22) includes a plurality of input channels (321, 322, 323, 324), each input channel receiving hit signals from a corresponding detector element (18) such that each input channel (321, 322, 323, 324) corresponds to a location at which each hit signal is received. A plurality of integrators (42) integrate signals from the input channels (32) to determine an energy value associated with each radiation hit. A plurality of analog-to-digital converters (441, 442, 443, 444) convert the integrated energy value into a digital energy value. A plurality of time to digital converters (40) receive the hit signals and generate a digital time stamp. OR logic (36, 38) relays signal hits from a subset of the plurality of input channels (32) to one of the ADC (44) and one of the time to digital converters (40), the subset including more than one input channel such that more than one input channel is connected with each ADC (44) and/or each time-to-digital converter (40). A register and read out (25) reads out the locations, the digital energy values, and the digital time stamps for hit signals.
摘要:
In a system for driving inertia-prone picture-reproducing devices, in particular liquid-crystal displays, in which a correcting value that depends on changes in the video signals from frame to frame is added to incoming video signals to compensate for the inertial effects and in which the corrected video signals are passed to the picture-reproducing device to form the correcting value, a model of the picture-reproducing device is provided that has a state variable as an output variable, the video signals as a first input variable and the state variable from a preceding frame as a second input variable. Furthermore, to derive the correcting value, a function having the incoming video signals and the state variable of the preceding variable as input variables and the corrected video signals as an output variable.
摘要:
A nuclear detector module (24) is housed within an electrically conductive hollow resonator element (18) that is to be used in a combined MR and nuclear imaging unit. The resonator element has an inner face (26) which is radiation transparent facing an examination region (14) and a plurality of other faces (28) disposed facing and spaced from an RF screen (22).
摘要:
In a combined system, a magnetic resonance (MR) scanner includes a magnet (10, 110) configured to generate a static magnetic field (B0) at least in a MR examination region (12) from which MR data are acquired. Radiation detectors (40, 41, 140) are configured to detect gamma rays generated by positron-electron annihilation events in a positron emission tomography (PET) examination region (70). The radiation 5 detectors include electron multiplier elements (60, 160) having a direction of electron acceleration (ae) arranged substantially parallel or anti-parallel with the static magnetic field (B0). In some embodiments, the magnet is an open magnet having first and second spaced apart magnet pole pieces (14, 15) disposed on opposite sides of a magnetic 10 resonance examination region, and the radiation detectors include first and second arrays (40, 41) of radiation detectors disposed with the first and second spaced apart magnet pole pieces.
摘要:
A diagnostic imaging device includes a signal processing circuit (22) processes signals from a detector array (16) which detects radiation from an imaging region (20). The hit signals are indicative of a corresponding detector (18) being hit by a radiation photon. The signal processing circuit (22) includes a plurality of input channels (321, 322, 323, 324), each input channel receiving hit signals from a corresponding detector element (18) such that each input channel (321, 322, 323, 324) corresponds to a location at which each hit signal is received. A plurality of integrators (42) integrate signals from the input channels (32) to determine an energy value associated with each radiation hit. A plurality of analog-to-digital converters (441, 442, 443, 444) convert the integrated energy value into a digital energy value. A plurality of time to digital converters (40) receive the hit signals and generate a digital time stamp. OR logic (36, 38) relays signal hits from a subset of the plurality of input channels (32) to one of the ADC (44) and one of the time to digital converters (40), the subset including more than one input channel such that more than one input channel is connected with each ADC (44) and/or each time-to-digital converter (40). A register and read out (25) reads out the locations, the digital energy values, and the digital time stamps for hit signals.
摘要:
An imaging ultrasound system is provided with an ultrasound transducer and an image processing unit for the acquisition of a three-dimensional ultrasound image of the body of a patient, and a catheter for carrying out a therapeutic or diagnostic intervention in the body of the patient. The catheter accommodates, in addition to the customary instruments necessary to carry out its task, three ultrasound receivers that are mounted at a distance from one another on the tip of the catheter and are capable of detecting the arrival of scan signals of the ultrasound transducer. The distance between the ultrasound transducer and the receivers can be calculated from the transit time of the scan signals. The receivers can thus be localized in space. Localization enables notably the selection of, for example, the plane from the three-dimensional ultrasound data that contains all three receivers of the catheter. The tip of the catheter can thus be automatically tracked and displayed on a monitor at all times without manual displacement of the ultrasound transducer being necessary.