Radiographic imaging apparatus and control method for the same

• US 8,903,048 B2
• Filed: 11/14/2013
• Issued: 12/02/2014
• Est. Priority Date: 07/26/2011
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Kitano, Kouichi, Nishino, Naoyuki, Ohta, Yasunori, Iwakiri, Naoto, Nakatsugawa, Haruyasu
• Primary Examiner(s): SONG, HOON K
• Application Number:
  US14/080,575
• Publication Number:
  US 20140072103A1
• Time in Patent Office: 383 Days
• Field of Search: 378114-116, 378/108, 378/110, 378/112, 378/97
• US Class Current: 378/115
• 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 6/542 involving control of exposure
• CPC Class Codes: A61B 6/56 Details of data transmission or power supply, e.g. use of slip rings
• CPC Class Codes: A61B 8/54 Control of the diagnostic device

Abstract

An X-ray imaging apparatus includes an FPD and short-circuited pixels. The FPD has pixels arranged in arrays for detecting an X-ray image. The short-circuited pixels detect a radiation dose of X-rays in the FPD. The X-ray imaging apparatus is changed over between first and second operating modes. The first operating mode is selected in case of combining with an X-ray generating apparatus with communication compatibility, and performs an exposure control for controlling a total radiation dose according to a detection signal from the short-circuited pixels. The second operating mode is selected in case of combining with an X-ray generating apparatus with communication incompatibility, and performs control of start synchronization for synchronizing operation of the FPD with the emission start of X-rays according to a detection signal from the short-circuited pixels. Thus, control of the X-ray imaging apparatus is changed over appropriately.

Claims

1. A radiographic imaging apparatus for use with a radiation generating apparatus for emitting radiation, comprising:

an image detector, having an imaging area in which plural pixels are arranged in arrays for storing a signal charge according to a radiation dose of said radiation upon receiving said radiation from said radiation generating apparatus, for detecting a radiation image by receiving radiation transmitted through an object;

a radiation detector for outputting a detection signal according to said radiation dose, in order to detect an emission start of said radiation from said radiation generating apparatus, and/or in order to measure a total radiation dose of said radiation;

a communication interface for communicating with said radiation generating apparatus;

a mode selector for selectively setting one of first and second operating modes;

wherein said first operating mode is used in case of combination with said radiation generating apparatus with which said communication interface has communication compatibility, for performing at least an exposure control for measuring said total radiation dose according to said detection signal from said radiation detector;

said second operating mode is used in case of combination with said radiation generating apparatus with which said communication interface has communication incompatibility, for performing at least a control of start synchronization for detecting said emission start according to said detection signal from said radiation detector and starting a storage step of storing said signal charge of said image detector in synchronism with said emission start;

a controller for controlling said image detector according to said one operating mode selectively set by said mode selector.

2. A radiographic imaging apparatus as defined in claim 1, wherein in said first operating mode, said controller starts said storage step in synchronism with an emission start signal transmitted to said communication interface by said radiation generating apparatus.

3. A radiographic imaging apparatus as defined in claim 2, wherein in said first operating mode, said controller measures said total radiation dose by accumulating said detection signal from said radiation detector, and when said total radiation dose reaches a threshold, causes said communication interface to transmit a stop signal to said radiation generating apparatus to stop emission of said radiation.

4. A radiographic imaging apparatus as defined in claim 3, wherein when said total radiation dose reaches said threshold, said controller terminates said storage step of said image detector.

5. A radiographic imaging apparatus as defined in claim 1, wherein in said second operating mode, said controller detects an emission end of said radiation from said radiation generating apparatus according to said detection signal from said radiation detector in addition to said control of said start synchronization, and terminates said storage step of said image detector in synchronism with said emission end.

6. A radiographic imaging apparatus as defined in claim 1, wherein in said second operating mode, said controller terminates said storage step upon a lapse of a predetermined time after a start of said storage step.

7. A radiographic imaging apparatus as defined in claim 2, wherein in said first and second operating modes, said controller carries out resetting in which a signal charge of said pixels is reset after detecting said emission start and before starting said storage step.

8. A radiographic imaging apparatus as defined in claim 1, wherein in said first operating mode, said controller performs said control of said start synchronization in addition to said exposure control.

9. A radiographic imaging apparatus as defined in claim 1, wherein said mode selector selects said operating modes according to manual operation for mode selection.

10. A radiographic imaging apparatus as defined in claim 1, wherein said mode selector detects communication compatibility or incompatibility with said radiation generating apparatus, and automatically selects said operating modes according to a result of detection.

11. A radiographic imaging apparatus as defined in claim 1, further comprising a notifier for notifying information as to which of said first and second operating modes is selected.

12. A radiographic imaging apparatus as defined in claim 2, wherein in said first operating mode, said emission start signal from said radiation generating apparatus is constituted by a pulse wave, and said communication interface notifies said controller of receiving said emission start signal upon detecting an edge of said pulse wave.

13. A radiographic imaging apparatus as defined in claim 1, wherein said radiation detector is disposed in said imaging area.

14. A radiographic imaging apparatus as defined in claim 13, wherein said radiation detector is disposed in each one of plural partial areas defined by splitting said imaging area;

said controller changes over said partial areas for use between said exposure control and said control of said start synchronization.

15. A radiographic imaging apparatus as defined in claim 14, wherein said plural partial areas include a central partial area disposed at a center of said imaging area and a side partial area disposed in a periphery of said central partial area;

said controller uses said central and side partial areas selectively in said exposure control and said control of said start synchronization.

16. A radiographic imaging apparatus as defined in claim 15, wherein said controller changes a sensitivity of said radiation detector in said partial areas for use in respectively said exposure control and said control of said start synchronization.

17. A radiographic imaging apparatus as defined in claim 13, wherein said radiation detector is a short-circuited pixel where one of said pixels is always short-circuited with a signal line for reading out said signal charge from said pixel, for outputting said signal charge to said signal line according to said radiation dose.

18. A radiographic imaging apparatus as defined in claim 1, wherein said image detector operates for motion imaging by receiving plural radiation pulses of said radiation emitted successively by said radiation generating apparatus;

in said motion imaging, said controller detects an edge of said radiation pulses according to said detection signal from said radiation detector, and synchronizes said storage step of said image detector with emission of said radiation pulses.

19. A radiographic imaging apparatus as defined in claim 18, wherein said controller measures said radiation dose per said radiation pulses according to said detection signal from said radiation detector, and controls an output gain of said signal charge according to a result of measurement.

20. A control method for a radiographic imaging apparatus for use with a radiation generating apparatus for emitting radiation, said radiographic imaging apparatus including an image detector, having an imaging area in which plural pixels are arranged in arrays for storing a signal charge according to a radiation dose of said radiation upon receiving said radiation from said radiation generating apparatus, for detecting a radiation image by receiving radiation transmitted through an object, a radiation detector for outputting a detection signal according to said radiation dose, in order to detect an emission start of said radiation from said radiation generating apparatus, and/or in order to measure a total radiation dose of said radiation, and a communication interface for communicating with said radiation generating apparatus, said control method comprising steps of:

selectively setting one of first and second operating modes;

wherein said first operating mode is used in case of combination with said radiation generating apparatus with which said communication interface has communication compatibility, for performing at least an exposure control for measuring said total radiation dose according to said detection signal from said radiation detector;

said second operating mode is used in case of combination with said radiation generating apparatus with which said communication interface has communication incompatibility, for performing at least a control of start synchronization for detecting said emission start according to said detection signal from said radiation detector and starting a storage step of storing said signal charge of said image detector in synchronism with said emission start;

controlling said image detector and said radiation detector according to said one operating mode selectively set by said mode setting step.