Simple charge division readouts for imaging scintillator arrays using a multi-channel PMT

Depth of interaction detection with enhanced position-sensitive proportional resistor network

“…Former Monte Carlo (MC) simulations of scintillation light transport within continuous crystals reinforce our model function [8]. Simulated light distributions for different DOIs together with the corresponding fitted functions are displayed in Fig.…”

“…The required changes consist in attaching an analog adder to the network. They do not affect the determination of the energy and the position computed as usual [8,9]. With the aid of the modified readout electronic, the DOI can be computed virtually in real time and simultaneously with the impact position and the energy of the gray.…”

“…However, this method misses the requirement of low detector dead times and costs, due to the huge number of electronic channels needed and the increased computational effort. A closer look at the position-sensitive proportional resistor chain (DPC) [8] frequently used in g-cameras reveals, that only a few inexpensive modifications are necessary to compute the light distribution's 2nd moment [6]. The DPC consists of a chain of equally valued resistances acting as a simple charge divider that allows the determination of the distribution's center of gravity from the currents extracted at both ends of the chain.…”

Performance of a DOI-encoding small animal PET system with monolithic scintillators

“…This method takes advantage of the strong correlation between the width of the undisturbed light distribution in continuous crystals and the g-ray's DOI. It consists of an inexpensive modification of the position-sensitive proportional resistor chain (DPC) readout [6,7] that allows the simultaneous measurement of the overall released amount of scintillation light, the centroids along the x and y spatial directions of the light distribution, and its bare second moment. The standard deviation, s light , can be computed from the digitized centroids and the bare second moment without any energy or spatial resolution degradation.…”

Preliminary study of different readout strategies for a positron emission mammograph head

“…We have initially evaluated the use of a discretized positioning circuit (DPC [2]) 64-input/4-output multiplexed readout, simultaneously connected to each of the four PMTs of one head. The rather limited count rates expected for the PEM system should prevent pile-up problems.…”