摘要:
Using standard or “off the shelf” cable to interconnect between the PET block detector and the detector circuit may save substantial costs given the number of PMTs in a PET system. Given space constraints, simple maintenance with reduced risk of disturbing cabling is desired, making ongoing use of standard cabling without adding further cabling desired. To implement digital gain control, a further communication is provided between the PET detector block and the detector circuit. Since the standard cable may not have additional wires for such communications and to reduce timing degradation, the PMT signals are combined, such as generating position and energy signals at the PET detector block. The four PMT signals are reduced to three signals without reduction in function, allowing a fourth twisted pair of wires in a CAT5 cable to be used for digital gain control.
摘要:
Using standard or “off the shelf” cable to interconnect between the PET block detector and the detector circuit may save substantial costs given the number of PMTs in a PET system. Given space constraints, simple maintenance with reduced risk of disturbing cabling is desired, making ongoing use of standard cabling without adding further cabling desired. To implement digital gain control, a further communication is provided between the PET detector block and the detector circuit. Since the standard cable may not have additional wires for such communications and to reduce timing degradation, the PMT signals are combined, such as generating position and energy signals at the PET detector block. The four PMT signals are reduced to three signals without reduction in function, allowing a fourth twisted pair of wires in a CAT5 cable to be used for digital gain control.
摘要:
A scintillation detector including one or more photomultiplier tubes, a scintillation block optically attached to the photomultiplier tubes, and a DC-coupled bleeder circuit combining outputs of dynodes of the photomultipliers to provide a DC-coupled dynode output together with a DC-coupled anode output of the photomultiplier tubes. The DC-coupled bleeder circuit includes a RF transformer. A positive high voltage supply also can be used together with a DC-coupled bleeder circuit for the anode outputs.
摘要:
A medical device with a high voltage connection line for carrying a high DC supply voltage has a control unit generating said high DC supply voltage which is fed through a first AC block unit to said high voltage connection line and generating a digital control signal fed through a first AC coupling unit to said high voltage connection line, and a remotely located unit a second AC block unit coupled to said high voltage connection line for receiving said high DC supply voltage and a second AC coupling unit coupled to said high voltage connection line for receiving said digital control signal.
摘要:
Signals generated by radiation sensors can be encoded to reduce the number of cables needed to transport information from a nuclear imaging apparatus to a processor for reconstruction. For example, signals from 16 radiation sensors can be encoded into three signals: T (top), L (left), and E (energy). This method of encoding signals can be capable of substantially reducing the number of signals, thereby reducing costs. In addition, reducing the number of signals could improve system timing performance by eliminating cable time-skew and facilitate the filter design by downgrading the circuit accuracy requirements such as group-delay error and filter signal skews.
摘要:
Signals generated by radiation sensors can be encoded to reduce the number of cables needed to transport information from a nuclear imaging apparatus to a processor for reconstruction. For example, signals from 16 radiation sensors can be encoded into three signals: T (top), L (left), and E (energy). This method of encoding signals can be capable of substantially reducing the number of signals, thereby reducing costs. In addition, reducing the number of signals could improve system timing performance by eliminating cable time-skew and facilitate the filter design by downgrading the circuit accuracy requirements such as group-delay error and filter signal skews.
摘要:
A medical device with a high voltage connection line for carrying a high DC supply voltage has a control unit generating said high DC supply voltage which is fed through a first AC block unit to said high voltage connection line and generating a digital control signal fed through a first AC coupling unit to said high voltage connection line, and a remotely located unit a second AC block unit coupled to said high voltage connection line for receiving said high DC supply voltage and a second AC coupling unit coupled to said high voltage connection line for receiving said digital control signal.
摘要:
A system for multiplexing photodetector signals from a scintillation detector. The system includes a detector module having a number of scintillator blocks, each scintillator block having a number of photosensors, and a number of multiplexing circuits. Each multiplexing circuit includes a number of inputs, a signal polarity inverter and at least one differential output attached to the signal polarity inverter. The multiplexing system inverts the polarity of preselected signals from the photosensors and selectively combines signals of different polarities to calculate event positioning and total energy.
摘要:
A scintillation detector including one or more photomultiplier tubes, a scintillation block optically attached to the photomultiplier tubes, and a DC-coupled bleeder circuit combining outputs of dynodes of the photomultipliers to provide a DC-coupled dynode output together with a DC-coupled anode output of the photomultiplier tubes. The DC-coupled bleeder circuit includes a RF transformer. A positive high voltage supply also can be used together with a DC-coupled bleeder circuit for the anode outputs.
摘要:
A data processing process and embodiment for optimizing the signal path for multi-modality imaging is described. The embodiment and process optimizes the signal to noise ratio in a positron emission tomography (PET) signal path utilizing scintillation crystals, avalanche photo diodes, and charge sensitive preamplifiers in a dual modality MRI/PET scanner. The dual use of both and analog pole zero circuit and a digital filter enables higher signal levels or a fixed ADC input range and thus a higher possible signal to noise ratio in the presence of significant pileup caused by high positron activity. The higher signal to noise ratio is needed in the PET signal architecture, because of the presence of non-modal time varying electromagnetic fields from the MR, which are a significant source of noise for the wideband PET signal modality.