Imagers in radiation therapy environment

1. An imager comprising:

an array of imager elements configured to generate image signals based on radiation received by the imager; and

a circuit configured to perform readout of the image signals, wherein the circuit is configured to be radiation hard;

wherein the imager is configured to remain fully functional even after the imager has been exposed to radiation resulting from at least 10 MV radiation beam with parameters of 100 kRad and 600 Mu/min.

2. The imager of claim 1 , wherein the circuit is configured to withstand at least 100 kRad of radiation.

3. The imager of claim 1 , wherein the circuit is configured to withstand at least 500 kRad of radiation.

4. The imager of claim 1 , wherein the circuit comprises readout and control circuit coupled to the array of imager elements, wherein the readout and control circuit is radiation hard.

5. The imager of claim 1 , wherein the circuit comprises a gate driver, and wherein the gate driver is radiation hard.

6. The imager of claim 1 , wherein the circuit of the imager comprises a commercial component that is not marketed as radiation hard, but has been tested as meeting certain radiation hardness requirement.

7. The imager of claim 1 , wherein the circuit of the imager comprise a commercial component that is marketed as radiation hard.

8. The imager of claim 1 , wherein the circuit of the imager has a component that is custom-designed to meet certain radiation hardness requirement.

9. The imager of claim 1 , further comprising a radiation shielding for protecting the imager from treatment radiation.

10. An imager comprising:

an array of imager elements configured to generate image signals for an image frame based on radiation received by the imager; and

a circuit configured to perform readout of the image signals, wherein the circuit is configured to be radiation hard;

wherein the circuit comprises a readout and control circuit coupled to the array of imager elements, wherein the readout and control circuit is configured to perform signal readout in synchronization with an operation of a treatment beam source;

wherein the readout and control circuit is configured to:

readout a first subset of the image signals for the image frame,

after the first subset of the image signals is readout, stop reading out any of the image signals to allow the treatment beam source to provide a treatment beam pulse, and

readout a second subset of the image signals for the image frame after the treatment beam source has provided the treatment beam pulse, the second subset of the image signals being different from the first subset of the image signals, and

wherein the first subset of the image signals and the second subset of the image signals are for different respective regions of the image frame.

11. The imager of claim 10 , wherein the readout and control circuit is configured to start the signal readout for the image frame at a pre-determined time or within a predetermined time period with respect to the treatment beam pulse.

12. The imager of claim 10 , wherein the treatment beam source is configured to hold off a delivery of the treatment beam pulse or multiple treatment beam pulses for a beam hold period.

13. The imager of claim 12 , wherein the beam hold period is long enough to allow the imager to reset the array of imager elements, receive imaging dose, and readout some of the image signals.

14. The imager of claim 1 , wherein the circuit comprises a layout configured to provide radiation hardness.

15. The imager of claim 14 , wherein the circuit comprises an edge-less transistor, an enclosed layout transistor (EL T), at least two transistors with guard rings between the two transistors, or any combination of the foregoing.

16. An imager comprising:

an array of imager elements configured to generate image signals based on radiation received by the imager; and

a circuit configured to perform readout of the image signals, wherein the circuit is configured to be radiation hard;

wherein the array of imager elements is configured to generate image signals based on photon counting; and

wherein the circuit is configured to readout a first subset of the image signals before a delivery of a treatment radiation beam, and to readout a second subset of the image signals after the delivery of the treatment radiation beam, and wherein the first subset of the image signals and the second subset of the image signals are for different respective regions of an image frame.

17. An imager comprising:

an array of imager elements configured to generate image signals for an image frame based on the radiation received by the imager; and

a circuit coupled to the array of imager elements, wherein the circuit is configured to perform signal readout in synchronization with an operation of a treatment beam source; wherein

the circuit is configured to:

readout a first subset of the image signals for the image frame,

after the first subset of the image signals is readout, stop reading out any of the image signals to allow the treatment beam source to provide a treatment beam pulse, and

readout a second subset of the image signals for the image frame after the treatment beam source has provided the treatment beam pulse, the second subset of the image signals being different from the first subset of the image signals, and

the first subset of the image signals and the second subset of the image signals are for different respective regions of the image frame.

18. The imager of claim 17 , wherein the circuit is configured to start the signal readout for the image frame at a pre-determined time or within a predetermined time period with respect to the treatment beam pulse.

19. The imager of claim 17 , wherein the treatment beam source is configured to hold off a delivery of the treatment beam pulse for a beam hold period.

20. The imager of claim 19 , wherein the beam hold period is long enough to allow the imager to reset the array of imager elements, receive imaging dose, and readout some of the image signals.

21. The imager of claim 17 , wherein the circuit is configured to be radiation hard.

22. The imager of claim 17 , wherein the circuit comprises readout and control circuit coupled to the array of imager elements, wherein the readout and control circuit is radiation hard.

23. The imager of claim 17 , wherein the circuit comprises a gate driver, and wherein the gate driver is radiation hard.

24. The imager of claim 17 , wherein the array of imager elements is configured to generate the image signals based on light signals provided by a scintillator layer.

25. The imager of claim 17 , wherein the array of imager elements is configured to generate the image signals based on charges provided by a conversion layer.

26. The imager of claim 17 , wherein the array of imager elements is configured to generate the image signals based on photon counting.

27. The imager of claim 17 , wherein the circuit is configured to perform signal readout in synchronization with the operation of the treatment beam source to prevent a band artifact, a dark line artifact, a bright line artifact, or any combination of the foregoing.

28. The imager of claim 1 , wherein the readout and control circuit is configured to suspend a signal-readout process when a treatment beam source is delivering a treatment beam pulse or multiple treatment beam pulses.

29. The imager of claim 1 , wherein the readout and control circuit is configured to perform signal readout for one or more lines of the imager during a treatment session when a treatment beam source is not delivering treatment energy, and to suspend signal readout for another line of the imager when the treatment beam source is delivering treatment energy.

30. The imager of claim 1 , wherein the array of imager elements is configured to generate the image signals based on light signals provided by a scintillator layer.

31. The imager of claim 1 , wherein the array of imager elements is configured to generate the image signals based on charges provided by a conversion layer.