Radiographic image detector, radiographic imaging apparatus, radiographic imaging system

• US 8,879,686 B2
• Filed: 12/20/2012
• Issued: 11/04/2014
• Est. Priority Date: 12/22/2011
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Okada, Yoshihiro, Iwakiri, Naoto, Inoue, Tomoki
• Primary Examiner(s): Kiknadze, Irakli
• Application Number:
  US13/722,510
• Publication Number:
  US 20130163716A1
• Time in Patent Office: 684 Days
• Field of Search: 378/4, 378/19, 378/98.8, 378/62
• US Class Current: 378/19
• CPC Class Codes: A61B 6/025 Tomosynthesis
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/0414 with compression means
• CPC Class Codes: A61B 6/4233 using matrix detectors
• CPC Class Codes: A61B 6/4452 the source unit and the detector unit being able to move relative to each other
• CPC Class Codes: A61B 6/502 for diagnosis of breast, i.e. mammography
• CPC Class Codes: G01N 23/046 using tomography, e.g. computed tomography [CT]
• 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 25/46 by combining or binning pixels
• 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

The present invention provides a radiographic image detector that may maintain even resolution in 6 directions before and after 3-pixel binning process or 4-pixel binning process. A radiation detector is disposed with plural pixels that have hexagonal shaped pixel regions, arrayed in a honeycomb pattern. Scan lines connected to TFT switches in each of the pixels are disposed one for each of the pixel rows. Grouped scan lines are also disposed one for each of the pixel rows for reading and combining 3 pixels or 4 pixels worth of charges at the same timing for plural pixel groups, each configured from 3 pixels or 4 pixels in a radiation detection element. ON signals are simultaneously sent by the grouped scanned lines to the TFT switches to perform 3-pixel binning or 4-pixel binning.

Claims

1. A radiographic image detector comprising:

a detection section including a plurality of pixels having hexagonal shaped pixel regions arrayed in a honeycomb pattern, each pixel including,

a sensor portion that generates charges according to irradiated radiation,

a first switching element that reads out the generated charges, and

a second switching element that reads out the generated charges;

a plurality of first scan lines, disposed one for each of a plurality of pixel rows configured by a plurality of the pixels adjacent to each other along a row direction, that are connected to a control terminal of the first switching element in each of the pixels of the corresponding pixel row;

a plurality of second scan lines, disposed one for each of the plurality of pixel rows, that are split into a plurality of line-groups and are connected to control terminals of the second switching elements of the pixel groups belonging to each respective group such that, when combining and reading charges from a plurality of pixel groups each configured from a plurality of adjacent pixels in the plurality of pixel rows, charge signals corresponding to combined charge amounts read out from the respective plurality of pixel groups are transmitted through different respective data lines; and

a plurality of data lines, disposed so as to respectively intersect with the plurality of first scan lines and the plurality of second scan lines, that transmit first charge signals corresponding to charges read out by the first switching elements in each of the plurality of pixels, and that transmit second charge signals corresponding to the combined charge amounts read by the second switching elements of the respective plurality of pixel groups,

wherein combinations of the pixels configuring respective pixel groups are determined such that, when a plurality of hexagonal shaped regions are formed adjacent to each other, the plurality of hexagonal shape regions results in a honeycomb pattern array, and wherein each of the hexagonal shape regions are formed by including inside one center of gravity of a region surrounded by an outline of the plurality of pixel groups configured by the respective 3 pixels or the respective 4 pixels, and by connecting together 6 individual centers of gravity present at the periphery of the one center of gravity.

2. The radiographic image detector of claim 1, wherein, when each of the plurality of pixel groups is configured from 3 pixels, control terminals of the second switching elements of each of the pixels in respective of the plurality of pixel groups alongside each other in a row direction are respectively connected to the second scan lines, and adjacent scan lines are commonly connected as a single line-group.

3. The radiographic image detector of claim 2, wherein the 3 pixels are 3 pixels disposed such that two adjoining sides of each of the pixels are respectively adjacent to one side of each of the other two pixels.

4. The radiographic image detector of claim 1, wherein, when the plurality of pixel groups are each configured by 4 pixels, the second scan lines are commonly connected in a line-group configured by an adjacent pair of the second scan lines, each pair of the second scan lines being configured by a second scan line connected to control terminals of the second switching elements of 3 individual pixels in a plurality of respective pixel groups alongside each other in the row direction, and the second scan line connected to the control terminals of the second switching elements of one individual pixel in each of the plurality of pixel groups.

5. The radiographic image detector of claim 4, wherein the 4 pixels are configured by 4 pixels made up from 3 pixels disposed such that two adjoining sides of each of the pixels are respectively adjacent to one side of the other 2 pixels out of the 3 pixels, and by 1 pixel disposed such that two adjoining sides are respectively adjacent to one side of 2 pixels out of the 3 pixels.

6. The radiographic image detector of claim 1, wherein the second switching elements connected to the plurality of second scan lines are controlled as blocks with shifted timings for each of the line-groups.

7. The radiographic image detector of claim 1, wherein the hexagonal shaped pixel regions are formed as regular hexagonal shapes.

8. The radiographic image detector of claim 1, wherein the hexagonal shaped pixel regions are formed as flattened hexagonal shapes.

9. The radiographic image detector of claim 8, wherein the hexagonal shaped pixel regions are formed flattened such that one diagonal line out of 3 diagonal lines passing through the center of each of the pixel regions is shorter than the other two diagonal lines and the other two diagonal lines are of equal length to each other.

10. The radiographic image detector of claim 1, wherein the plurality of data lines are laid out bent along one portion of the hexagonal shaped pixel region periphery.

11. The radiographic image detector of claim 1, wherein the sensor portions includes a semiconductor film that receives irradiation with the radiation and generates charges, and

wherein, the charges are accumulated in a storage capacitor provided in each of the plurality of pixels and the charges accumulated in the storage capacitor are read by the first switching element and the second switching element.

12. The radiographic image detector of claim 11 further comprising, a plurality of common lines that connect together one electrode of each of the storage capacitors and that fixes the electrodes to a specific electrical potential.

13. The radiographic image detector of claim 12, wherein the plurality of common lines extend between the plurality of data lines in a straight line shape or in a substantially straight line shape.

14. The radiographic image detector of claim 13, wherein the plurality of common lines are connected to the plurality of data lines through the storage capacitors, the first switching elements and the second switching elements.

15. The radiographic image detector of claim 14, wherein the plurality of first scan lines, the plurality of second scan lines, the plurality of data lines, the plurality of common lines, the first switching elements, and the second switching elements, are disposed at a lower layer side of the sensor portions.

16. The radiographic image detector of claim 1, wherein the sensor portions includes a scintillator that converts the radiation that has been irradiated into visible light, and

wherein, after the converted visible light has been converted into charges by a semiconductor layer, the charges are read out by the first switching element and the second switching element.

17. A radiographic imaging apparatus comprising:

the radiographic image detector of claim 1; and

a radiation irradiation section provided facing the radiographic image detector and that irradiates radiation onto an imaging subject above the radiographic image detector,

wherein a radiographic image is imaged with the radiographic image detector.

18. The radiographic imaging apparatus of claim 17, wherein the radiation irradiation section irradiates radiation onto the imaging subject from each of a plurality of different imaging angles.

19. A radiographic imaging system comprising:

the radiographic imaging apparatus of claim 18;

control section that instructs the radiographic imaging apparatus to perform imaging of a radiographic image, and that acquires a plurality of radiographic images from the radiographic image detector that have been imaged by the radiographic image detector at each of the imaging angles; and

tomographic image generation section that generates a plurality of tomographic images reconstructed with reference to a detection face of the radiographic image detector based on the plurality of radiographic images acquired by the control section;

wherein the control section includes, switching section that, based on an external instruction, switches between a first radiographic image acquisition mode that acquires a first radiographic image configured from image data in single-pixel units of a radiographic image detection device, and a second radiographic image acquisition mode that acquires a second radiographic image configured from image data in multi-pixel units of the radiographic image detection device, and

wherein the radiation irradiation section has a range of image angles for irradiating radiation onto the imaging subject that is larger when imaging to acquire the first radiographic image than when imaging to acquire the second radiographic image.

20. The radiographic imaging system of claim 19, wherein the thickness of the tomographic image generated by the tomographic image generation section based on the first radiographic images is thinner than the thickness of the tomographic images generated based on the second radiographic images.

21. A radiographic imaging system comprising:

the radiographic imaging apparatus of claim 17; and

control section that instructs the radiographic imaging apparatus to perform imaging of a radiographic image, and that acquires a radiographic image from the radiographic imaging apparatus,

wherein the control section includes, switching section that, based on an external instruction, switches between a first radiographic image acquisition mode that acquires a first radiographic image configured from image data in single-pixel units of a radiographic image detection device, and a second radiographic image acquisition mode that acquires a second radiographic image configured from image data in multi-pixel units of the radiographic image detection device.

22. The radiographic imaging system of claim 21, wherein, when instructed to perform imaging to acquire the second radiographic image, the control section controls the radiation irradiation section such that the radiation amount irradiated onto the imaging subject is an amount according to the multi-pixel unit and smaller than when imaging to acquire the first radiographic image.