Plasma panel based ionizing radiation detector
A radiation detector is formed from a plasma panel that includes a front substrate, and a back substrate that forms a generally parallel gap with the front substrate. X (column) and Y (row) electrodes are coupled by gas discharge events to define one or more pixels. Impedances are coupled to the X and Y electrodes, and a power supply is coupled to one or both types of electrodes. Discharge event detectors are coupled to the impedances.
1. An ionizing-radiation counting detector comprising:
a first substrate;
a second substrate generally parallel to said first substrate and forming a gap with said first substrate;
a gas contained within said gap;
at least one first electrode coupled to said second substrate;
at least one second electrode electrically coupled to said first electrode;
a first impedance coupled to said first electrode;
a second impedance coupled to said second electrode;
a power supply coupled to at least one of said electrodes;
a first discharge event detector coupled to said first impedance;
a second discharge event detector coupled to said second impedance;
a plurality of pixels, each pixel capable of outputting a gas discharge pulse upon interaction with ionizing radiation; wherein each gas discharge pulse is counted as having approximately an equal value; and
circuitry for detecting if a gas discharge pulse is output from the pixels, and for counting each gas discharge pulse as an individual event.
2. The ionizing-radiation counting detector of claim 1 , wherein said first electrode and said second electrode are electronically coupled to define each pixel.
3. The ionizing-radiation counting detector of claim 2 , wherein said first electrode is an X-electrode and said second electrode is a Y-electrode.
4. The ionizing-radiation counting detector of claim 1 , further comprising:
at least one first driver coupled to said first electrode; and
at least one second driver coupled to said second electrode.
5. The ionizing-radiation counting detector of claim 1 , further comprising:
time-stamp circuitry coupled to said first discharge event detector and said second discharge event detector that time-stamps discharge events detected by said first discharge event detector and said second discharge event detector.
6. The ionizing-radiation counting detector of claim 5 , further comprising:
discharge event data storage coupled to said time-stamp circuitry for storing coupled discharge events detected by said first discharge event detector and said second discharge event detector that occur at generally the same time.
7. The ionizing-radiation counting detector of claim 6 , further comprising:
sensitivity control coupled to said discharge event data storage for providing feedback information to said power supply and said first and second discharge event detectors.
8. The ionizing-radiation counting detector of claim 3 , further comprising a conversion layer coupled to said first substrate.
9. The ionizing-radiation counting detector of claim 1 , further comprising:
a hermetic seal coupling said first substrate to said second substrate; and
peripheral edge spacers to define said gap.
10. The ionizing-radiation counting detector of claim 1 , wherein said second electrode is coupled to said first substrate.
11. The ionizing-radiation counting detector of claim 1 , wherein said second electrode is coupled to said second substrate.
12. The ionizing-radiation counting detector of claim 11 , wherein a gas discharge between said first and second electrodes is a surface discharge shape.
13. The ionizing-radiation counting detector of claim 10 , wherein a gas discharge between said first and second substrates and at an intersection of said first and second electrodes is a columnar discharge shape.
14. An ionizing-radiation counting detector comprising:
a first substrate;
a conversion material on said first substrate;
a second substrate generally parallel to said first substrate and forming a gas gap with said first substrate;
a first electrode;
a second electrode forming at least one pixel with said first electrode;
a first impedance coupled to said first electrode;
a second impedance coupled to said second electrode;
a power supply coupled to at least one of said electrodes;
first circuitry coupled to said first impedance for detecting a gas-discharge counting event in said first electrode;
second circuitry coupled to said second impedance for detecting the gas-discharge counting event in said second electrode; and
a plurality of pixels, each pixel capable of outputting a gas discharge pulse upon interaction with ionizing radiation; wherein each gas discharge pulse is counted as having approximately an equal value; and
wherein the first and second circuitry is adapted to detect if a gas discharge pulse is output from the pixels, and counting each gas discharge pulse as an individual event.
15. The ionizing-radiation counting detector of claim 14 , further comprising a dielectric layer coupled to said first substrate.
16. The ionizing-radiation counting detector of claim 14 , wherein said first electrode is an X-electrode and said second electrode is a Y-electrode.
17. The ionizing-radiation counting detector of claim 14 , further comprising:
at least one first driver coupled to said first electrode; and
at least one second driver coupled to said second electrode.
18. The ionizing-radiation counting detector of claim 14 , further comprising:
time-stamp circuitry coupled to said first circuitry and said second circuitry that time-stamps ionizing-radiation counting events detected by said first circuitry and said second circuitry.
19. The ionizing-radiation counting detector of claim 14 , wherein said pixel is formed from a gas discharge event.
20. A method of detecting ionizing-radiation based on a counting of gas discharge events comprising:
receiving ionizing-radiation at a first substrate of a plasma panel, said plasma panel having a second substrate;
creating at least one free-electron within a conversion layer coupled to said first substrate in response to the received ionizing-radiation, said creating resulting in an emittance of an electron out of said conversion layer and into a gas contained within a gap between said first and second substrates;
causing a gas-discharge event at a pixel site of the plasma panel; and
counting a plurality of said events at a first pulse detector coupled to a first electrode and at a second pulse detector coupled to a second electrode wherein each of said events is counted as approximately a same value.