CN217278960U - High-resolution X-ray flat panel detector - Google Patents

Abstract

The utility model relates to a high-resolution X-ray flat panel detector, which comprises a fluorescent reflection layer, a scintillation screen, an array collimator, a light cone, a CCD/CMOS image sensor, a data acquisition and transmission system, and the detector is packaged through a shielding shell. . The detector uses a new type of GAGG:Ce single crystal scintillator to make a scintillation screen. An array collimator is added between the scintillation screen and the light cone to limit the range of fluorescence angles that the scintillation screen can output, so as to reduce fluorescence crosstalk and improve the spatial resolution of the detector. Compared with the common light cone coupled X-ray flat panel detector, the detector has stable performance and can achieve higher detection spatial resolution when using the same thickness of the scintillation screen.

Description

A high-resolution X-ray flat panel detector

technical field

The utility model relates to the technical field of radiation detection, in particular to a high-resolution X-ray flat panel detector.

Background technique

X-ray detectors are an important part of X-ray computed tomography (CT) systems. With the wide application of micro/nano focal ray source CT, there is an increasing demand for X-ray detectors with higher spatial resolution. urgent. The CCD/CMOS X-ray flat-panel detector based on light cone coupling has good radiation resistance and can achieve high spatial resolution. It is the first choice for laboratory X-ray detection with high spatial resolution. There is still a big gap between the actual spatial resolution that can be achieved by the currently used light cone-coupled CCD/CMOS X-ray flat panel detector products and the optical resolution limit of the CCD/CMOS image sensor. The main factor causing this gap is the X-ray Radiation scattering and fluorescence crosstalk between pixels after rays incident on a scintillation screen. For micro/nano focus X-ray sources with tube voltage less than 160kV, the ray scattering crosstalk between adjacent pixels is small, and the fluorescence crosstalk is the main factor. Suppressing the fluorescence crosstalk is the most effective method to improve the spatial resolution. However, because the pixel size is too small, conventional methods such as adding a reflective layer between the pixels of the scintillation screen cannot achieve fluorescence crosstalk isolation. At present, the method to improve the spatial resolution of light cone-coupled CCD/CMOS X-ray flat panel detectors is to reduce the thickness of the scintillation screen to reduce fluorescence crosstalk, but reducing the thickness of the scintillation screen will reduce the X-ray energy deposition of the scintillation screen, resulting in detection efficiency. decrease.

There is an urgent need for a high-resolution detector that can realize high-efficiency X-ray detection.

Utility model content

The purpose of this utility model is to provide a high-resolution light cone-coupled CCD/CMOS X-ray flat panel detector based on fluorescence crosstalk collimation. The detector adds an array collimator between the fluorescence output surface of the scintillation screen and the light cone. Limits the reception of crosstalk fluorescence beyond the set range of the scintillation screen, improving the spatial resolution of the detector without reducing the thickness of the scintillation screen.

The purpose of the present utility model is achieved through such a technical scheme, which includes a fluorescent reflection layer, a scintillation screen, an array collimator, a light cone, a CCD/CMOS image sensor, a data acquisition and transmission system, and a shielding shell;

The fluorescent reflection layer, the scintillation screen, the array collimator, the light cone, and the CCD/CMOS image sensor are sequentially stacked and connected by a colorless and transparent coupling agent.

Further: the scintillation screen is made of GAGG:Ce single crystal scintillator, and the size of its detection plane is not smaller than the size of the light-cone photosensitive surface.

Further: the array collimator is made of a low numerical aperture optical fiber panel, and the size of its light transmission surface is not smaller than the size of the light cone photosensitive surface.

Further: the fluorescent reflective layer is made of a high-reflectivity ESR reflective film.

Further: the colorless and transparent coupling agent is high refractive index epoxy resin glue.

Further: the big end of the light cone is coupled with the array collimator, and the small end is coupled with the CCD/CMOS image sensor.

Further: the shielding shell is made of metal with high atomic number and high density.

Further: an X-ray incident window is provided on the shielding shell, and the X-ray incident window is made of a full carbon fiber board.

Due to the adoption of the above-mentioned technical solutions, the utility model has the following advantages: the scintillation screen is made of a novel high-light-yield GAGG:Ce single crystal scintillator, which solves the problems of easy deliquescence and unstable performance of the traditional CsI (TI), and solves the problem of The problem of low fluorescence detection efficiency caused by the opacity of GOS(Tb) scintillator ensures the conversion efficiency of X-ray detection and improves the stability of the scintillation screen; adding an array collimator suppresses the fluorescence crosstalk range without reducing the thickness of the scintillation screen , Under the condition of ensuring the X-ray detection efficiency, the spatial resolution of the detector is improved.

Other advantages, objects and features of the present invention will be set forth in the description that follows, and to the extent that will be apparent to those skilled in the art based on a study of the following, or may be Lessons are learned from the practice of the present invention. The objectives and other advantages of the present invention may be realized and attained by the following description.

Description of drawings

The accompanying drawings of the present utility model are described as follows.

FIG. 1 is a cross-sectional view of the detector structure of the present invention.

In the figure: 1. Fluorescent reflection layer; 2. Scintillation screen; 3. Array collimator; 4. Light cone; 5. CCD/CMOS image sensor; 6. Data acquisition and transmission system; 7. Shielding shell; 8. X Ray entrance window.

Detailed ways

The utility model will be further described below in conjunction with the accompanying drawings and embodiments.

As shown in FIG. 1, a high-resolution X-ray flat panel detector includes a fluorescent reflection layer 1, a scintillation screen 2, an array collimator 3, a light cone 4, a CCD/CMOS image sensor 5, a data acquisition and transmission system 6, shield shell 7;

The fluorescent reflection layer 1 , the scintillation screen 2 , the array collimator 3 , the light cone 4 , and the CCD/CMOS image sensor 5 are sequentially stacked and connected by a colorless and transparent coupling agent.

The scintillation screen 2 is made of GAGG:Ce single crystal scintillator, and the size of its detection plane is not smaller than the size of the photosensitive surface of the light cone 4 .

In this embodiment, the GAGG:Ce single crystal scintillator has the advantages of stable structure and high light yield. The use of GAGG:Ce single crystal scintillator to make a scintillation screen solves the problems that the traditional CsI(TI) is easy to deliquescence and has unstable performance. , which solves the problem of low fluorescence detection efficiency caused by the opacity of traditional GOS (Tb) scintillators, and improves the stability of the scintillation screen while ensuring the conversion efficiency of X-ray detection.

As shown in FIG. 1 , the array collimator 3 is made of a low numerical aperture optical fiber panel, and the size of its light transmission surface is not smaller than the size of the photosensitive surface of the light cone 4 .

In this embodiment, the array collimator is made of a low numerical aperture optical fiber panel with mature technology and low price. The array collimator suppresses the fluorescence crosstalk range, without reducing the thickness of the scintillation screen and ensuring the X-ray detection efficiency. Improves the spatial resolution of the detector.

The fluorescent reflection layer 1 is made of a high reflectivity ESR reflection film.

The colorless and transparent coupling agent is high-refractive-index epoxy resin glue.

The big end of the light cone 4 is coupled with the array collimator 3 , and the small end is coupled with the CCD/CMOS image sensor 5 .

The shielding shell 7 is made of high atomic number, high density metal.

The shielding shell 7 is provided with an X-ray incident window 8, and the X-ray incident window 8 is made of a full carbon fiber board.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should The technical solutions are modified or equivalently replaced without departing from the purpose and scope of the technical solutions, and they should all be included in the scope of the claims of the present invention.

Claims (8)

1. A high-resolution X-ray flat panel detector is characterized in that: the device comprises a fluorescent reflecting layer (1), a scintillation screen (2), an array collimator (3), a light cone (4), a CCD/CMOS image sensor (5), a data acquisition and transmission system (6) and a shielding shell (7);

the fluorescent reflecting layer (1), the scintillation screen (2), the array collimator (3), the light cone (4) and the CCD/CMOS image sensor (5) are sequentially overlapped and connected by a colorless transparent coupling agent.

2. A high resolution X-ray flat panel detector as claimed in claim 1 wherein: the scintillation screen (2) is made of a GAGG Ce monocrystal scintillator, and the size of a detection plane of the scintillation screen is not smaller than that of a light sensitive surface of the light cone (4).

3. The high-resolution X-ray flat panel detector according to claim 1, wherein: the array collimator (3) is made of a low numerical aperture optical fiber panel, and the size of a light transmission surface of the array collimator is not smaller than that of a light sensing surface of the light cone (4).

4. The high-resolution X-ray flat panel detector according to claim 1, wherein: the fluorescent reflection layer (1) is made of ESR reflection films with high reflectivity.

5. The high-resolution X-ray flat panel detector according to claim 1, wherein: the colorless transparent coupling agent is epoxy resin glue with high refractive index.

6. The high-resolution X-ray flat panel detector according to claim 1, wherein: the large end of the light cone (4) is coupled with the array collimator (3), and the small end of the light cone is coupled with the CCD/CMOS image sensor (5).

7. The high-resolution X-ray flat panel detector according to claim 1, wherein: the shielding shell (7) is made of high atomic number and high density metal.

8. The high-resolution X-ray flat panel detector according to claim 1 or 7, wherein: an X-ray incidence window (8) is arranged on the shielding shell (7), and the X-ray incidence window (8) is made of an all-carbon fiber plate.

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