Reading apparatus for x-ray detector and method for using reading apparatus, and x-ray detector

1. A reading apparatus for an X-ray detector, the reading apparatus comprising:

a control circuit;

a compensation circuit; and

a processing circuit, wherein the control circuit is configured to provide, in a first phase, a first signal to an input terminal of the compensation circuit according to a reference signal and a dark current in a sense device of the X-ray detector, and provide, in a second phase, a second signal from the sense device to the input terminal of the compensation circuit, wherein the compensation circuit is configured to generate, in the first phase, a compensation signal according to the first signal, and compensate, in the second phase, the second signal according to the compensation signal to generate a third signal, wherein the processing circuit is configured to process the third signal, and wherein the compensation circuit comprises:

a calculation unit, configured to generate the compensation signal according to the first signal;

a storage unit, configured to store the compensation signal; and

a compensation unit, configured to compensate the second signal according to the compensation signal stored, to generate the third signal, wherein the compensation unit comprises a summator, wherein a first input terminal of the summator receives the compensation signal, wherein a second input terminal of the summator receives the second signal, and wherein an output terminal of the summator provides the third signal.

2. The reading apparatus according to claim 1 , wherein the control circuit comprises:

a first switching element, wherein an end of the first switching element is coupled to an input terminal of the reading apparatus, and wherein another end of the first switching element is coupled to the reference signal; and

a second switching element, wherein an end of the second switching element is coupled to the input terminal of the reading apparatus, and wherein another end of the second switching element is coupled to the input terminal of the compensation circuit.

3. The reading apparatus according to claim 1 , wherein the calculation unit comprises a subtracter; and

wherein a first input terminal of the subtracter receives the first signal, wherein a second input terminal of the subtracter receives the reference signal, and wherein an output terminal of the subtracter provides the compensation signal.

4. The reading apparatus according to claim 1 , wherein the calculation unit comprises:

a first amplifier, wherein an output terminal of the first amplifier is coupled to the storage unit;

a first resistor, wherein an end of the first resistor is coupled to a first input terminal of the first amplifier, and wherein another end of the first resistor is coupled to the output terminal of the first amplifier;

a second resistor, wherein an end of the second resistor is coupled to the first input terminal of the first amplifier, and wherein another end of the second resistor is coupled to the input terminal of the compensation circuit;

a third resistor, wherein an end of the third resistor is coupled to a second input terminal of the first amplifier, and wherein another end of the third resistor is coupled to the reference signal; and

a fourth resistor, wherein an end of the fourth resistor is coupled to the second input terminal of the first amplifier, and wherein another end of the fourth resistor is grounded.

5. The reading apparatus according to claim 4 , wherein the first resistor, the second resistor, the third resistor, and the fourth resistor have an equal resistance value.

6. The reading apparatus according to claim 1 , wherein the compensation unit comprises:

a second amplifier, wherein an output terminal of the second amplifier is coupled to the processing circuit;

a fifth resistor, wherein an end of the fifth resistor is coupled to a first input terminal of the second amplifier, and wherein another end of the fifth resistor is coupled to the output terminal of the second amplifier;

a sixth resistor, wherein an end of the sixth resistor is coupled to the first input terminal of the second amplifier, and wherein another end of the sixth resistor is grounded;

a seventh resistor, wherein an end of the seventh resistor is coupled to a second input terminal of the second amplifier, and wherein another end of the seventh resistor is coupled to the second signal;

an eighth resistor, wherein an end of the eighth resistor is coupled to the second input terminal of the second amplifier, and wherein another end of the eighth resistor is coupled to the storage unit to receive the compensation signal; and

a ninth resistor, wherein an end of the ninth resistor is coupled to the second input terminal of the second amplifier, and wherein another end of the ninth resistor is grounded.

7. The reading apparatus according to claim 6 , wherein the fifth resistor, the seventh resistor, and the eighth resistor have an equal resistance value, and wherein the sixth resistor and the ninth resistor have an equal resistance value.

8. The reading apparatus according to claim 1 , wherein the processing circuit comprises:

a third amplifier, wherein a first input terminal of the third amplifier is coupled to the output terminal of the compensation circuit, wherein a second input terminal of the third amplifier is coupled to the reference signal, and wherein an output terminal of the third amplifier is configured to provide the third signal; and

a first capacitor coupled between the first input terminal of the third amplifier and the output terminal of the third amplifier.

9. The reading apparatus according to claim 8 , wherein the control circuit comprises:

a first switching element, wherein an end of the first switching element is coupled to the input terminal of the reading apparatus, and wherein another end of the first switching element is coupled to the first input terminal of the third amplifier; and

a second switching element, wherein an end of the second switching element is coupled to the input terminal of the reading apparatus, and wherein another end of the second switching element is coupled to the input terminal of the compensation circuit.

10. The reading apparatus according to claim 1 further comprising:

a reset unit coupled between an input terminal of the processing circuit and an output terminal of the processing circuit.

11. The reading apparatus according to claim 10 , wherein the processing circuit comprises:

a third amplifier, wherein a first input terminal of the third amplifier is coupled to the output terminal of the compensation circuit, wherein a second input terminal of the third amplifier is coupled to the reference signal, and wherein an output terminal of the third amplifier is configured to provide the third signal; and

a first capacitor coupled between the first input terminal of the third amplifier and the output terminal of the third amplifier,

wherein the reset unit comprises a third switching element, and wherein the third switching element is coupled between the first input terminal of the third amplifier and the output terminal of the third amplifier.

12. The reading apparatus according to claim 1 further comprising:

a filter, configured to filter the third signal processed; and

an analog-to-digital converter, configured to convert the third signal filtered.

13. The X-ray detector according to claim 12 , wherein the control circuit comprises:

a first switching element, wherein an end of the first switching element is coupled to an input terminal of the reading apparatus, and wherein another end of the first switching element is coupled to the reference signal; and

a second switching element, wherein an end of the second switching element is coupled to the input terminal of the reading apparatus, and wherein another end of the second switching element is coupled to the input terminal of the compensation circuit.

14. An X-ray detector comprising:

a reading apparatus comprising the reading apparatus according to claim 1 ; and

a sense device.

15. The X-ray detector according to claim 14 , wherein the compensation circuit comprises:

a calculation unit, configured to generate the compensation signal according to the first signal;

a storage unit, configured to store the compensation signal; and

a compensation unit, configured to compensate the second signal according to the compensation signal stored, to generate the third signal.

16. A method for using the reading apparatus according to claim 1 , the method configured to read an X-ray detector, and the method comprising:

providing, in a first phase, a first signal to an input terminal of the compensation circuit according to a reference signal and a dark current in a sense device of the X-ray detector, such that a compensation signal is generated according to the first signal; and

providing, in a second phase, a second signal from the sense device to the input terminal of the compensation circuit, compensating the second signal according to the compensation signal to generate a third signal, and processing the third signal.

17. The method according to claim 16 , wherein providing, in the first phase, the first signal comprises providing a reference voltage to the input terminal of the compensation circuit in response to the sense device being in a dark state, and then stopping providing the reference voltage, wherein after stopping providing the reference voltage, the first signal is provided to the input terminal as a result that a voltage at the input terminal is smaller than the reference voltage due to electric leakage caused by the dark current of the sense device, wherein generating the compensation signal comprises calculating a difference, as the compensation signal, between the first signal and the reference signal, wherein compensating, in the second phase, the second signal to generate the third signal comprises calculating a sum, as the third signal, of the second signal and the compensation signal, and wherein processing the third signal comprises filtering and performing analog-to-digital conversion on the third signal.