Radiological image conversion panel, method of manufacturing the same, and radiological image detection apparatus

• US 10,126,435 B2
• Filed: 09/29/2015
• Issued: 11/13/2018
• Est. Priority Date: 12/27/2010
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Kaneko, Yasuhisa, Nakatsugawa, Haruyasu, Sato, Keiichirou, Kitada, Makoto, Miura, Kei
• Primary Examiner(s): Green, Yara B
• Application Number:
  US14/869,009
• Publication Number:
  US 20160018534A1
• Time in Patent Office: 1,141 Days
• CPC Class Codes: A61B 6/4216 using storage phosphor screens
• CPC Class Codes: B05D 5/06 to obtain multicolour or other optical effects B05D5/02 takes precedence
• CPC Class Codes: C23C 14/243 Crucibles for source material C23C14/28, C23C14/30 take precedence
• CPC Class Codes: G01T 1/20185 Coupling means between the photodiode and the scintillator, e.g. optical couplings using adhesives with wavelength-shifting fibres
• CPC Class Codes: G01T 1/20186 Position of the photodiode with respect to the incoming radiation, e.g. in the front of, below or sideways the scintillator
• CPC Class Codes: G01T 1/20187 Position of the scintillator with respect to the photodiode, e.g. photodiode surrounding the crystal, the crystal surrounding the photodiode, shape or size of the scintillator
• CPC Class Codes: G01T 1/202 the detector being a crystal
• CPC Class Codes: G21K 2004/06 with a phosphor layer
• CPC Class Codes: G21K 4/00 Conversion screens for the conversion of the spatial distribution of X-rays or particle radiation into visible images, e.g. fluoroscopic screens photographic processes using X-ray intensifiers G03C5/17; discharge tubes comprising luminescent screens H01J1/62; cathode ray tubes for X-ray conversion with optical output H01J31/50

Abstract

A radiological image conversion panel 2 is provided with a phosphor 18 containing a fluorescent material that emits fluorescence by radiation exposure, in which the phosphor includes, a columnar section 34 formed by a group of columnar crystals which are obtained through columnar growth of crystals of the fluorescent material, and a non-columnar section 36, the columnar section and the non-columnar section are integrally formed to overlap in a crystal growth direction of the columnar crystals, and a thickness of the non-columnar section along the crystal growth direction is non-uniform in a region of at least a part of the non-columnar section.

Claims

1. A radiological image detection apparatus comprising:

a radiological image conversion panel comprising a phosphor containing a fluorescent material that emits fluorescence by radiation exposure; and

a sensor panel which detects fluorescence generated from the radiological image conversion panel and converts the fluorescence into an electrical signal,

wherein the phosphor comprises a columnar section formed by a group of columnar crystals which are obtained through columnar growth of crystals of a fluorescent material, and a non-columnar section,

the columnar section and the non-columnar section are integrally formed on the sensor panel to overlap in a crystal growth direction of the columnar crystals so that the sensor panel, the non-columnar section and the columnar section are provided in this order,

a thickness of the non-columnar section along the crystal growth direction is non-uniform in a region of at least a part of the non-columnar section,

a difference between a maximum thickness and a minimum thickness in a central region of the non-columnar section is less than a difference between a maximum thickness and a minimum thickness in a peripheral region of the non-columnar section,

a diameter of each crystal constituting the non-columnar section is 0.5 μ

m or more and 7.0 μ

m or less,

the crystals of the non-columnar section irregularly overlap, and some crystals thereof are fused to each other in a thickness direction or an in-plane direction, and

the non-columnar section includes a non-crystalline part.

2. The radiological image detection apparatus of claim 1, wherein a deviation in a thickness distribution in a central region of the non-columnar section is less than a deviation in a thickness distribution in a peripheral region of the non-columnar section.

3. The radiological image detection apparatus of claim 1, wherein the thickness of the non-columnar section is non-uniform only in the peripheral region.

4. The radiological image detection apparatus of claim 1, wherein the thickness of the non-columnar section is distributed within a range of 5 μ

m or more and 125 μ

m or less.

5. The radiological image detection apparatus of claim 1, which has a radiation entrance surface at the sensor panel side.

6. The radiological image detection apparatus of claim 1, which has a radiation entrance surface at the radiological image conversion panel side.

7. A method of manufacturing the radiological image detection apparatus of claim 1, wherein the non-columnar section and the columnar section are formed in this order on the sensor panel by depositing crystals of the fluorescent material on the sensor panel by a vapor deposition method with varying at least one condition of a degree of vacuum and a temperature of the sensor panel,

wherein when the non-columnar section is formed, the crystals of the fluorescent material are deposited on the sensor panel by varying a degree of vacuum.

8. The radiological image detection apparatus of claim 1, wherein t2/t1 is from 0.01 to 0.25, where t1 represents a thickness of the columnar section and t2 represents a thickness of the non-columnar section.

9. A radiological image detection apparatus comprising:

a radiological image conversion panel comprising a phosphor containing a fluorescent material that emits fluorescence by radiation exposure; and

a sensor panel which detects fluorescence generated from the radiological image conversion panel and converts the fluorescence into an electrical signal,

wherein the phosphor comprises a columnar section formed by a group of columnar crystals which are obtained through columnar growth of crystals of a fluorescent material, and a non-columnar section,

the columnar section and the non-columnar section are integrally formed on the sensor panel to overlap in a crystal growth direction of the columnar crystals so that the sensor panel, the non-columnar section and the columnar section are provided in this order,

a thickness of the non-columnar section along the crystal growth direction is non-uniform in a region of at least a part of the non-columnar section,

a deviation in a thickness distribution in a central region of the non-columnar section is less than a deviation in a thickness distribution in a peripheral region of the non-columnar section,

a diameter of each crystal constituting the non-columnar section is 0.5 μ

m or more and 7.0 μ

m or less,

the crystals of the non-columnar section irregularly overlap, and some crystals thereof are fused to each other in a thickness direction or an in-plane direction, and

the non-columnar section includes a non-crystalline part.

10. The radiological image detection apparatus of claim 9, wherein the thickness of the non-columnar section is distributed within a range of 5 μ

m or more and 125 μ

m or less.

11. The radiological image detection apparatus of claim 9, which has a radiation entrance surface at the sensor panel side.

12. The radiological image detection apparatus of claim 9, which has a radiation entrance surface at the radiological image conversion panel side.

13. A method of manufacturing the radiological image detection apparatus of claim 9, wherein the non-columnar section and the columnar section are formed in this order on the sensor panel by depositing crystals of the fluorescent material on the sensor panel by a vapor deposition method with varying at least one condition of a degree of vacuum and a temperature of the sensor panel,

wherein when the non-columnar section is formed, the crystals of the fluorescent material are deposited on the sensor panel by varying a degree of vacuum.

14. The radiological image detection apparatus of claim 9, wherein t2/t1 is from 0.01 to 0.25, where t1 represents a thickness of the columnar section and t2 represents a thickness of the non-columnar section.