Spectrally and spatially resolved x-ray and particle detection system
A detection system for an x-ray or charged particle imaging system utilizes high bandgap, direct conversion x-ray detection materials. The signal of the x-ray/charged particle projection is recorded in a spatial light modulator such as a liquid crystal (LC) light valve. The light valve is then read-out by a polarized light optical microscope and a high speed camera. The camera is used to track the blooming spots in the light valve to resolve their intensity, and relate that intensity of the input x-ray photon or charged particle. This allows of spatially resolved, imaging, x-ray and/or charged particle spectrometer.
1. A spectrally and spatially resolved x-ray and/or charged particle detection system, comprising:
a photoconductive detector;
an optical microscope for reading out the photoconductive detector;
a camera coupled to the photoconductive detector by the optical microscope; and
a computer system that obtains images generated by the camera and tracks the response of the photoconductive detector to x-ray photons and/or charged particles over time.
2. The detection system as claimed in claim 1 , wherein the computer system tracks blooming in the photoconductive detector induced by the x-ray photons or charged particles to resolve locations on the photoconductive detector and energy of the x-ray photons or charged particles.
3. The detection system as claimed in claim 1 , wherein the computer system determines the energy of the x-ray photons or charged particles by reference to an energy/intensity map that relates a maximum spot intensity to an energy of the received x-ray photons or charged particle.
4. The detection system as claimed in claim 1 , wherein an interval between successive frames captured by the camera is less than a relaxation time of the photoconductive detector.
5. The detection system as claimed in claim 4 , wherein an interval between successive frames captured by the camera is less than 1 millisecond.
6. The detection system as claimed in claim 1 , wherein the photoconductive detector detects x-ray photons.
7. The detection system as claimed in claim 1 , wherein the photoconductive x-ray/charged particle detector comprises a liquid crystal light valve and photoconductive detector layer.
8. The detection system as claimed in claim 7 , wherein the photoconductive detector layer comprises bismuth, lead, mercury, tellurium, selenium, or thallium.
9. The detection system as claimed in claim 1 , wherein the optical microscope is a polarization light microscope.
10. The detection system as claimed in claim 1 , wherein the optical microscope reads-out the photoconductive detector in transmission.
11. The detection system as claimed in claim 1 , wherein the optical microscope reads-out the photoconductive detector in reflection.
12. A particle detection method, comprising:
converting x-ray photons and/or charged particles into electron-hole pairs in a photoconductive detector;
reading out the photoconductive detector with a camera coupled to the photoconductive detector; and
processing images generated by the camera and tracking the response of the photoconductive detector to x-ray photons or charged particles over time to determine the position and the energy of the x-ray photons or charged particles.
13. The method of claim 12 employing a system comprising:
the photoconductive detector;
an optical microscope for reading out the photoconductive detector;
the camera coupled to the photoconductive detector by the optical microscope; and
a computer system that obtains images generated by the camera and tracks the response of the photoconductive detector to x-ray photons and/or charged particles over time.
14. An imaging system, comprising:
an object stage system for holding an object;
a photoconductive detector for detecting x-ray photons or charged particles from the object;
a camera coupled to the photoconductive detector by an optical microscope; and
a computer system that obtains the images generated by the camera and tracks the response of the photoconductive detector to x-ray photons or charged particles over time to image the object and determine an energy of the x-ray photons or charged particles.
15. A method for calibrating a x-ray photon or charged particle detection system, comprising:
generating x-ray photons or charged particles of known energy;
converting particles into electron-hole pairs in a photoconductive detector;
reading out the photoconductive detector with a camera; and
processing images generated by the camera and tracking spots generated by the x-ray photons or charged particles received by the photoconductive detector and determining a relationship between the spots and the energy of the x-ray photons or charged particles.
16. The method of claim 15 employing a system comprising:
the photoconductive detector;
an optical microscope for reading out the photoconductive detector;
the camera coupled to the photoconductive detector by the optical microscope; and
a computer system that obtains images generated by the camera and tracks the response of the photoconductive detector to x-ray photons and/or charged particles over time.