Radiation imaging apparatus, method for controlling the same, and radiation image detection device

• US 9,322,928 B2
• Filed: 12/23/2013
• Issued: 04/26/2016
• Est. Priority Date: 07/26/2011
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Iwakiri, Naoto, Nishino, Naoyuki, Ohta, Yasunori, Kitano, Kouichi, Nakatsugawa, Haruyasu
• Primary Examiner(s): Kao, Glen
• Application Number:
  US14/139,306
• Publication Number:
  US 20140110595A1
• Time in Patent Office: 855 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 6/4233 using matrix detectors
• CPC Class Codes: A61B 6/4283 characterised by a detector unit being housed in a cassette
• CPC Class Codes: A61B 6/54 Control of apparatus or devices for radiation diagnosis
• CPC Class Codes: G01T 1/16 Measuring radiation intensity G01T1/29 takes precedence ; self-powered detectors G01T3/006; using an ionisation chamber filled with a liquid or solid, e.g. frozen liquid, dielectric G01T3/008
• CPC Class Codes: H04N 23/30 for generating image signals from X-rays
• CPC Class Codes: H04N 25/53 Control of the integration time
• CPC Class Codes: H04N 25/532 by controlling global shutters in CMOS SSIS
• CPC Class Codes: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors
• CPC Class Codes: H04N 5/32 Transforming X-rays cameras or camera modules for generating image signals from X-rays H04N23/30; circuitry of SSIS for transforming X-rays into image signals H04N25/30

Abstract

A determination section of an FPD checks external information against a determination table and determines whether detection of a rise of X-ray pulses is allowed based on an output voltage from a short-circuited pixel. The FPD detects X-ray images. The external information is transmitted from an imaging control device. The X-ray pulses are sequentially generated by an X-ray generating apparatus. A controller selects a pulse irradiation mode in a case where the detection of the rise of the X-ray pulse is allowed. If not, a successive irradiation mode is selected. In the pulse irradiation mode, the rise and the fall of the X-ray pulse are detected and timing of storage operation is synchronized with the detected timing of the rise. In the successive irradiation mode, the storage operation is performed at predetermined time intervals without the detection of the rise and the fall of the X-ray pulse.

Claims

1. An X-ray radiation imaging apparatus used in combination with an X-ray radiation generating apparatus, for performing fluoroscopy, the X-ray radiation generating apparatus successively generating pulses of X-ray radiation to perform pulse irradiation, the X-ray radiation imaging apparatus comprising:

an image detector for detecting an X-ray radiation image of an object, the image detector having an image capture field in which pixels are arranged in a matrix, each pixel storing a signal charge in accordance with a dose of the X-ray radiation;

an X-ray radiation detector for detecting the X-ray radiation and outputting a detection signal in accordance with the dose;

a controller for allowing the image detector to operate in one of a pulse irradiation mode and a successive irradiation mode, the controller detecting a rise and a fall of the pulse of the X-ray radiation based on the detection signal outputted from the X-ray radiation detector and determining start timing of a storage operation based on timing of detecting the rise and determining start timing of a readout operation based on timing of detecting the fall in the pulse irradiation mode, the signal charge being stored in the storage operation, the stored signal charge being read out in the readout operation, the storage operation and the readout operation being repeated alternately at predetermined time intervals without detection of the rise and the fall of the pulse of the X-ray radiation in the successive irradiation mode;

a determination section for obtaining external information, which includes information related to the X-ray radiation generating apparatus and imaging conditions, and determining whether the image detector is allowed to be set to the pulse irradiation mode based on the obtained external information; and

a mode setting section for setting the image detector to one of the pulse irradiation mode and the successive irradiation mode based on a result of determination of the determination section, the mode setting section setting the image detector to the pulse irradiation mode in a case where the image detector is allowed to be set to the pulse irradiation mode, the mode setting section setting the image detector to the successive irradiation mode in a case where the image detector is not allowed to be set to the pulse irradiation mode.

2. The X-ray radiation imaging apparatus of claim 1, wherein the external information is information for determining an overlapping state of a rising edge and a falling edge of two successive pulses of the X-ray radiation during the pulse irradiation.

3. The X-ray radiation imaging apparatus of claim 2, wherein the information related to the X-ray radiation generating apparatus is a type of an X-ray radiation tube constituting the X-ray radiation generating apparatus, and the imaging condition is at least one of a frame rate of the fluoroscopy, a tube current supplied to the X-ray radiation tube, and a tube voltage supplied to the X-ray radiation tube.

4. The X-ray radiation imaging apparatus of claim 3, further comprising a determination table against which the determination section checks the external information to determine whether the pulse irradiation mode is allowed.

5. The X-ray radiation imaging apparatus of claim 4, wherein the determination table stores information of whether the pulse irradiation mode is allowed, per combination of three types of information, and the three types of information include the type of the X-ray radiation tube, at least one of the tube current and the tube voltage, and the frame rate.

6. The X-ray radiation imaging apparatus of claim 4, wherein the determination section sets the image detector to the successive irradiation mode in a case where the determination section cannot obtain the external information necessary for determining whether the pulse irradiation mode is allowed.

7. The X-ray radiation imaging apparatus of claim 4, further comprising an X-ray radiation image detection device having the image detector, the controller, and a housing for accommodating the image detector and the controller.

8. The X-ray radiation imaging apparatus of claim 7, wherein the X-ray radiation image detection device comprises the determination section.

9. The X-ray radiation imaging apparatus of claim 8, wherein the X-ray radiation image detection device has the determination table.

10. The X-ray radiation imaging apparatus of claim 7, wherein the X-ray radiation image detection device has the X-ray radiation detector.

11. The X-ray radiation imaging apparatus of claim 7, further comprising a peripheral device separate from the X-ray radiation image detection device, and the determination section is provided in the peripheral device.

12. The X-ray radiation imaging apparatus of claim 2, wherein the determination section calculates the overlapping state based on the external information, to determine whether the pulse irradiation mode is allowed.

13. The X-ray radiation imaging apparatus of claim 1, wherein the controller allows starting the storage operation at the timing of detecting the rise of the pulse of the X-ray radiation in the pulse irradiation mode.

14. The X-ray radiation imaging apparatus of claim 1, wherein the controller ends the storage operation and allows starting the readout operation at the timing of detecting the fall of the pulse of the X-ray radiation in the pulse irradiation mode.

15. The X-ray radiation imaging apparatus of claim 1, wherein the X-ray radiation imaging apparatus is capable of performing still image capture in addition to the fluoroscopy.

16. The X-ray radiation imaging apparatus of claim 15, wherein the controller detects the rise and the fall of the pulse of the X-ray radiation based on the detection signal of the X-ray radiation detector and synchronizes the storage operation with the rise and synchronizes the readout operation with the fall in the still image capture, in a manner similar to the pulse irradiation mode.

17. The X-ray radiation imaging apparatus of claim 1, wherein the image capture field includes at least one short-circuited pixel in addition to pixels, and the at least one short-circuited pixel is constantly short-circuited with a signal line for reading out the signal charge from the pixel, and

wherein the X-ray radiation detector is the at least one short-circuited pixel which constantly outputs a signal charge corresponding to the dose to the signal line.

18. An X-ray radiation image detection device used in combination with an X-ray radiation generating apparatus, for performing fluoroscopy, the X-ray radiation generating apparatus successively generating pulses of X-ray radiation to perform pulse irradiation, the X-ray radiation image detection device comprising:

an image detector for detecting an X-ray radiation image of an object, the image detector having an image capture field in which pixels are arranged in a matrix, each pixel storing a signal charge in accordance with a dose of the X-ray radiation;

an X-ray radiation detector for detecting the X-ray radiation and outputting a detection signal in accordance with the dose;

a controller for allowing the image detector to operate in one of a pulse irradiation mode and a successive irradiation mode, the controller detecting a rise and a fall of the pulse of the X-ray radiation based on the detection signal outputted from the X-ray radiation detector and determining start timing of a storage operation based on timing of detecting the rise and determining start timing of a readout operation based on timing of detecting the fall in the pulse irradiation mode, the signal charge being stored in the storage operation, the stored signal charge being read out in the readout operation, the storage operation and the readout operation being repeated alternately at predetermined time intervals without detection of the rise and the fall of the pulse of the X-ray radiation in the successive irradiation mode;

a determination section for obtaining external information, which includes information related to the X-ray radiation generating apparatus and imaging conditions, and determining whether the image detector is allowed to be set to the pulse irradiation mode based on the obtained external information; and

a mode setting section for setting the image detector to one of the pulse irradiation mode and the successive irradiation mode based on a result of determination of the determination section, the mode setting section setting the image detector to the pulse irradiation mode in a case where the image detector is allowed to be set to the pulse irradiation mode, the mode setting section setting the image detector to the successive irradiation mode in a case where the image detector is not allowed to be set to the pulse irradiation mode.

19. A method for controlling an X-ray radiation imaging apparatus used in combination with an X-ray radiation generating apparatus, for performing fluoroscopy, the X-ray radiation generating apparatus successively generating pulses of X-ray radiation to perform pulse irradiation, the X-ray radiation imaging apparatus comprising an X-ray radiation detector and an image detector for detecting an X-ray radiation image of an object, the image detector having pixels arranged in a matrix, each pixel storing a signal charge in accordance with a dose of the X-ray radiation, the X-ray radiation detector detecting the X-ray radiation and outputting a detection signal in accordance with the dose;

the method comprising the steps of;

obtaining external information that includes information related to the X-ray radiation generating apparatus and imaging conditions;

determining whether the image detector is allowed to be set to a pulse irradiation mode based on the external information, a rise and a fall of the pulse of the X-ray radiation being detected based on the detection signal outputted from the X-ray radiation detector and start timing of a storage operation for storing the signal charge being determined based on timing of detecting the rise and start timing of a readout operation for reading out the signal charge being determined based on timing of detecting the fall in the pulse irradiation mode;

setting the image detector to the pulse irradiation mode in a case where the image detector is allowed to be set to the pulse irradiation mode, and setting the image detector to a successive irradiation mode in a case where the image detector is not allowed to be set to the pulse irradiation mode, the storage operation and the readout operation being repeated alternately at predetermined time intervals without detection of the rise and the fall of the pulse of the X-ray radiation in the successive irradiation mode; and

controlling the image detector in one of the pulse irradiation mode and the successive irradiation mode to which the image detector is set.