Single light photon counting radiation detector and data transmission methods
A single photon radiation detector is designed for a particular radiation source fluence, such that an incident radiation photon strikes a scintillator monolith, creating scintillation photons, which are amplified by appropriately sized channels of photomultipliers optically coupled to the scintillator monolith. The photomultiplier output is electronically shaped into a corresponding stream of scintillation pulses (otherwise referred to as scintillation photons) that pass through a comparator to produce a bitstream of the detected scintillation photons, which is sampled into a field programmable gate array (FPGA) acting as a giga-sample transceiver to produce time-to-digital conversions, capable of producing an output data stream of 10's-of-giga-samples per second or more. Appropriate design ensures sparsity of scintillation photon arrival, so that each photon in the bitstream corresponds to a single incident scintillation photon.
1 . A single photon radiation detector, comprising:
(a) a scintillator monolith; and
(b) at least one detector channel comprising:
(i) a photomultiplier in optical communication with the scintillator monolith;
(ii) a front end signal shaper in electronic communication with the photomultiplier;
(iii) wherein an input of a single incident radiation photon interacts with the scintillator monolith, thereby creating one or more scintillation photons;
(iv) wherein the one or more of the scintillation photons impinge upon the photomultiplier, thereby creating a corresponding photomultiplier output signal;
(v) wherein the photomultiplier output signal is processed by the front end signal shaper to produce a stream of scintillator pulses;
(vi) a comparator that inputs the stream of scintillator pulses to output a photon counting bitstream; and
(vii) a gigabit transceiver that converts the photon counting bitstream into a time-to-digital (TDC) converted digital output.
2 . The single photon radiation detector of claim 1 , wherein the photomultiplier comprises an analog Silicon Photomultiplier (SiPM).
3 . The single photon radiation detector of claim 1 , wherein the comparator comprises a low-voltage differential signaling (LVDS) device.
4 . The single photon radiation detector of claim 1 , further comprising:
an aggregator;
wherein the aggregator consolidates the TDC converted digital outputs of the various channels as inputs to form an aggregated overall detector output.
5 . The single photon radiation detector of claim 4 , wherein the aggregated overall detector output comprises:
the TDC converted digital output of the channel; and
a channel number corresponding to the detector channel;
whereby the detector channel physical location may be determined by the channel number.
6 . The single photon radiation detector of claim 4 , wherein the aggregator comprises a gigabit transceiver within an FPGA, wherein the gigabit transceiver operates at a speed of 10 giga-samples per second or faster.
7 . The single photon radiation detector of claim 4 , wherein the comparator comprises a Field Programmable Gate Array (FPGA).
8 . The single photon radiation detector of claim 1 , wherein the photon counting bitstream has a one-to-one correspondence to an arrival of the scintillation photons upon the channel photomultiplier.
9 . The single photon radiation detector of claim 1 , further comprising:
a bandpass optical filter disposed between the scintillator monolith and the detector channel;
wherein spurious Geiger discharges between adjacent photomultipliers are reduced.
10 . The single photon radiation detector of claim 1 , wherein the scintillator monolith comprises a Cherenkov radiator.
11 . A method of single photon radiation detection, comprising:
(a) providing a scintillator monolith; and
(b) providing at least one detector channel comprising:
(i) a photomultiplier in optical communication with the scintillator monolith;
(ii) a front end signal shaper in electronic communication with the photomultiplier;
(iii) wherein an input of a single incident radiation photon interacts with the scintillator monolith, thereby creating one or more scintillation photons;
(iv) wherein the one or more of the scintillation photons impinge upon the photomultiplier, thereby creating a corresponding photomultiplier output signal;
(c) processing the photomultiplier output signal by the front end signal shaper to produce a stream of scintillator pulses;
(d) inputting the stream of scintillator pulses into a comparator to output a photon counting bitstream; and
(e) providing a gigabit transceiver to convert the photon counting bitstream into a time-to-digital (TDC) converted digital output.
12 . The method of single photon radiation detection of claim 11 , wherein the photomultiplier comprises an analog Silicon Photomultiplier (SiPM).
13 . The method of single photon radiation detection of claim 11 , wherein the comparator comprises a low-voltage differential signaling (LVDS) device.
14 . The method of single photon radiation detection of claim 11 , further comprising:
aggregating the TDC converted digital outputs of the various channels as inputs to form an aggregated overall detector output.
15 . The method of single photon radiation detection of claim 14 , wherein the aggregated overall detector output comprises:
the TDC converted digital output of the channel; and
a channel number corresponding to the detector channel;
whereby the detector channel physical location may be determined by the channel number.
16 . The method of single photon radiation detection of claim 14 , wherein the aggregating step is performed on an aggregator comprising:
a gigabit transceiver within an FPGA;
wherein the gigabit transceiver operates at a speed of 10 giga-samples per second or faster.
17 . The method of single photon radiation detection of claim 11 , wherein the comparator comprises a Field Programmable Gate Array (FPGA).
18 . The method of single photon radiation detection of claim 11 , wherein the photon counting bitstream has a one-to-one correspondence to an arrival of the scintillation photons upon the channel photomultiplier.
19 . The method of single photon radiation detection of claim 11 , further comprising:
providing a bandpass optical filter disposed between the scintillator monolith and the detector channel;
wherein spurious Geiger discharges between adjacent photomultipliers are reduced.
20 . The method of single photon radiation detection of claim 11 , wherein the scintillator monolith comprises a Cherenkov radiator.