RADIATION DETECTOR, RADIOGRAPHIC IMAGING DEVICE AND RADIOGRAPHIC IMAGING SYSTEM

• US 20130009065A1
• Filed: 06/21/2012
• Published: 01/10/2013
• Est. Priority Date: 07/07/2011
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: OKADA, Yoshihiro
• Granted Patent: US 9,366,766 B2
• Time in Patent Office: Days
• US Class Current: 250/363.01
• CPC Class Codes: G01T 1/20184 Detector read-out circuitry, e.g. for clearing of traps, compensating for traps or compensating for direct hits
• 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 radiation detector, a radiographic imaging device and a radiographic imaging system that may detect radiation with high precision. Namely, in the radiation detector, radiation detection pixels include detection TFTs, and light that has been converted from radiation is illuminated directly from a scintillator onto the detection TFTs. Accordingly, leak current occurs in semiconductor active layers of the detection TFTs corresponding to the amount (intensity) of the illuminated light, and the leak current flows in to signal lines. Accordingly, radiation may be detected by monitoring the leak current, and enables timings, such as the start of irradiation of radiation, to be detected.

Claims

1. A radiation detector comprising:

a sensor portion, provided to each of a plurality of pixels disposed in a matrix, that generates charges due to irradiation of radiation;

a switching element, provided to each of the plurality of pixels, that output charges generated in the sensor portion to a signal line; and

a radiation detection section comprising,

a conversion section that converts the irradiated radiation into light, and that illuminates the light, and

a semiconductor element that outputs electric signals according to the illuminated light to the signal line or to a radiation detection signal line.

2. The radiation detector of claim 1, wherein the semiconductor element is directly illuminated with light from the conversion section.

3. The radiation detector of claim 1, wherein the sensor portion comprises:

a photoelectric conversion section provided for each of the pixels; and

a conversion section, provided so as to overlap with the photoelectric conversion sections of the plurality of the pixels, that converts radiation into light and illuminates the light,

wherein the semiconductor element provided below the conversion section of the sensor portion and not overlapping with the photoelectric conversion section.

4. The radiation detector of claim 1, wherein the sensor portion comprises:

a conversion section that converts radiation into light and illuminates the light; and

a photoelectric conversion section provided below the conversion section such that the photoelectric conversion section overlaps with a section of the conversion section,

wherein the switching element is provided below the photoelectric conversion section, and

wherein the semiconductor element is provided below a region of the conversion section not overlapping with the photoelectric conversion section.

5. The radiation detector of claim 1 wherein the semiconductor element is a switching element applied with a bias voltage.

6. The radiation detector of claim 1 wherein the semiconductor element is a switching element comprising a gate electrode to which a voltage is applied for controlling an amount of current of the electric signals output.

7. The radiation detector of claim 1 wherein one of the radiation detection sections is provided to each of a predetermined plurality of radiation detection pixels that are employed for radiation detection from among the plurality of pixels.

8. The radiation detector of claim 1 wherein one of the radiation detection sections is provided for each of the plurality of pixels.

9. The radiation detector of claim 8 wherein, out of the plurality of pixels, the radiation detection section provided to each pixel, other than the radiation detection pixels, is not connected to the signal line, a radiation detection signal line, and any combination thereof.

10. The radiation detector of claim 1 wherein the radiation detection section is provided between the sensor portion and the sensor portion of adjacent pixels.

11. The radiation detector of claim 1 wherein the correspondence relationship between irradiated radiation amount and charge amount generated by the sensor portion, matches the correspondence relationship between the irradiated radiation amount and charge amount of the electric signals output from the semiconductor element.

12. The radiation detector of claim 1 wherein the sensor portion comprises a light blocking section that blocks light from being illuminated onto the photoelectric conversion element other than the light illuminated from the conversion section.

13. A radiographic imaging device comprising:

the radiation detector of claim 1;

a detection section that detects radiation amount based on charges output from the radiation detection section of the radiation detector; and

an imaging section that acquires a radiographic image based on charge amount output from the sensor portions.

14. The radiographic imaging device of claim 13 further comprising:

a read circuit, provided to each of the signal lines of the radiation detector, that read out the charges output to the signal lines,

wherein the radiation detection section of the radiation detector outputs the electric signals to the signal line.

15. A radiographic imaging system comprising:

a radiation irradiation section; and

the radiographic imaging device of claim 13 that images a radiographic image of radiation irradiated from the radiation irradiation section.