A scintillator with multi-level light intensity adjustment

Abstract

The present invention discloses a scintillator with multi-level light intensity adjustment, comprising a plurality of scintillator elements arranged in an array structure with gaps therebetween, each scintillator element comprising: a top surface and a plurality of side surfaces for receiving radiation, a first reflection layer covering the top surface and a second reflection layer covering the side surfaces; a carbon film is arranged between the top surface and the first reflection layer, and a sharpening sheet is covered on the outside of the first reflection layer; an anti-crosstalk metal layer is arranged between adjacent scintillator elements. The anti-crosstalk metal layer is made of one or more metals with an atomic number ≥ 60; the sharpening sheet is made of one or more metal materials with an atomic number ≤ 30. The present invention sharpens the rays through the sharpening sheet, cuts off the low-energy ray signals, and ensures that the high-energy ray signals are more uniform; the carbon film with a nanometer-level thickness can diffract and enhance the rays, increase the uniformity and energy intensity of the rays; the anti-crosstalk metal layer reduces the mutual crosstalk of the rays, and ensures the stability of the output signal.

Description

Technical Field

[0001] The present invention generally relates to a device for detecting radiation in CT imaging and other radiation imaging systems, and more particularly to a scintillator with multi-level light intensity adjustment. Background Art

[0002] A scintillation detector is a device that converts high-energy rays (X / γ rays, etc.) into ultraviolet light or visible light, and then converts the optical signal into an electrical signal through photomultiplier tubes and other photon detection devices, and finally presents the information of the interaction between high-energy rays and the detected material in the form of a digital signal. At present, scintillation detectors have been widely used in the fields of medical treatment, national defense, security inspection, etc. The most core functional component of the scintillation detector is the scintillator array, which is the conversion medium between high-energy rays and optical signals. The scintillator array is composed of multiple scintillator elements arranged in a two-dimensional array. When light propagates in a traditional scintillator array, due to the non-uniformity of energy of the high-energy rays incident on each scintillator element, and the crosstalk of high-energy rays and electrons between adjacent scintillator elements, the intensity of the emitted light will be uneven, which will lead to poor stability of the output signal.

[0003] Improving the uniformity and emission rate of light in the scintillator array will, on the one hand, reduce the radiation dose of high-energy rays under the same detection signal output conditions and create green and safe detection devices; on the other hand, it can also reduce the difficulty of receiving and processing signals at the back end of the detector, further reducing the manufacturing cost of the detector matching equipment. Summary of the invention

[0004] In order to solve the above technical problems, the purpose of the present invention is to provide a scintillator capable of adjusting light intensity in multiple stages, so as to improve the emission uniformity and emission rate of X-rays through the multi-stage dimming of the scintillator.

[0005] In view of the above problems, a technical solution adopted by the present invention is to provide a scintillator with multi-level light intensity adjustment, comprising a plurality of scintillator primitives, wherein the plurality of scintillator primitives are arranged in an array structure with gaps therebetween, and each of the scintillator primitives comprises:

[0006] A top surface and multiple side surfaces for receiving radiation; a reflective layer, comprising a first reflective layer covering the top surface and a second reflective layer covering the side surfaces; characterized in that:

[0007] A carbon film is disposed between the top surface and the first reflective layer.

[0008] Furthermore, the carbon film has a thickness of 0.01 to 10 nm.

[0009] Furthermore, the scintillator element further includes a sharpening sheet covering the first reflective layer.

[0010] Furthermore, an anti-crosstalk metal layer is arranged between adjacent scintillator elements, and the anti-crosstalk metal layer is arranged between the second reflective layers of adjacent scintillator elements.

[0011] Furthermore, the scintillator element comprises: scintillator crystal, scintillator glass, scintillator ceramic and plastic scintillator; the scintillator crystal comprises thallium-doped sodium iodide (NaI:Tl), thallium-doped cesium iodide (CsI:Tl), bismuth germanate (Bi4Ge3O 12 , BGO), cerium-doped yttrium silicate ((Lu,Y)2SiO5:Ce, LYSO), cadmium tungstate (CdWO4, CWO), barium fluoride (BaF2), cerium-doped lanthanum chloride (LaCl3:Ce), cerium-doped lanthanum bromide (LaBr3:Ce), cerium-doped lithium yttrium hexachloride (Cs2LiYCl6:Ce, CLYC), cerium-doped gadolinium aluminum garnet structure (Gd3(Al,Ga)5O 12 :Ce, GGAG); the scintillating ceramic is a garnet structure, and its structural formula can be expressed as: (AB) 3+x C 5-x O 12 , wherein: A is a luminescent rare earth element, which can be Ce, Pr, Nd, Eu, Tb, Er, Dy, Tm, Ho or a combination thereof; B can be Sc, Y, Gd, Yb, Lu or a combination thereof; C can be Al, Ga or a combination of Al and Ga;

[0012] The scintillating ceramic can also be (Gd 1-x-y Pr x D y )2O2S ceramics, wherein D can be one or two of Ce, Pr, Eu, Nd, Sm, Gd, Ho, Yb, Tm.

[0013] Furthermore, the reflection layer is made of epoxy resin mixed with a reflection medium; the thickness of the first reflection layer is 0.1 to 3 mm; the thickness of the second reflection layer is 0.1 to 1.0 mm.

[0014] Furthermore, the anti-crosstalk metal layer is composed of one or more metals with an atomic number ≥60.

[0015] Furthermore, the anti-crosstalk metal layer has a thickness of 0.1 to 0.3 mm.

[0016] Furthermore, the anti-crosstalk metal layer is composed of one or more of W, Pt, Au, and Pb.

[0017] Furthermore, the sharpening sheet is made of one or more metal materials with an atomic number ≤30.

[0018] Furthermore, the sharpening sheet has a thickness of 0.2 to 1.0 mm.

[0019] Furthermore, the sharpening sheet is made of one or more materials selected from Al and Cu, and has a thickness of 0.2 to 1.0 mm.

[0020] The beneficial effects of the present invention are as follows: the sharpening sheet can sharpen the rays, cut off the low-energy ray signals, and ensure that the high-energy ray signals are more uniform; the carbon film with nanometer-level thickness has a wavelength that matches the rays, can coherently diffract with the rays, and increase the uniformity and energy intensity of the rays; the anti-crosstalk metal layer plays a role in reducing the mutual crosstalk of the rays, thereby ensuring the stability of the output signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of an embodiment of the present invention;

[0022] Figure 2 It is a structural schematic diagram of a comparative example of the present invention. DETAILED DESCRIPTION

[0023] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0024] See also Figure 1 The structure of an embodiment of the present invention is shown in the figure: a scintillator with multi-level light intensity adjustment includes a plurality of scintillator elements 1, which are arranged in a two-dimensional array structure with gaps therebetween, and the width of the gaps between adjacent scintillator elements 1 is d=0.4 mm.

[0025] Each of the scintillator elements 1 comprises: a top surface for receiving radiation and multiple side surfaces; the top surface is sequentially covered with a carbon film 2, a first reflection layer 3, and a sharpening sheet 4 from the inside to the outside, the side surfaces are covered with a second reflection layer 5, and an anti-crosstalk metal layer 6 is arranged between adjacent scintillator elements 1, and the anti-crosstalk metal layer 6 is arranged between the second reflection layers 3 of adjacent scintillator elements 1. The carbon film 2, the first reflection layer 3, and the sharpening sheet 4 are all matched with the top surface size of the scintillator; the first reflection layer 3 and the second reflection layer 5 are both composed of epoxy resin doped with a reflective medium; the thickness of the first reflection layer 3 is: 0.5 mm; the thickness of the second reflection layer 5 = d - the thickness of the anti-crosstalk metal layer 6.

[0026] Under the condition that the overall size of the scintillator and the size of a single scintillator unit 1 are the same, the thickness of the carbon film 2 in the scintillator, the material and thickness of the sharpening sheet 4, and the material and thickness of the anti-crosstalk metal layer 6 are changed to form embodiments 1 to 12.

[0027] See also Figure 2 , is a schematic diagram of the structure of the scintillator in the comparative example of the present invention. The scintillator structure in the comparative example of the present invention includes: a plurality of scintillator primitives 1', the scintillator primitives 1' are arranged in a two-dimensional array structure with gaps, and the gap width d' between adjacent scintillator primitives 1' is 0.4mm. Each scintillator primitive 1' includes: a top surface for receiving radiation and a plurality of side surfaces; the top surface is covered with a first reflective layer 3', and the side surfaces are covered with a second reflective layer 5', and the first reflective layer 3' and the second reflective layer 5' are both composed of epoxy resin doped with a reflective medium; the thickness of the first reflective layer 3' is 0.5mm: the thickness of the second reflective layer 5' is: 0.4mm; the overall size of the scintillator in the comparative example of the present invention is the same as the overall size of the scintillator in the embodiment, and the size of a single scintillator primitive 1' in the comparative example of the present invention is the same as the size of the scintillator primitive 1 in the embodiment. Comparative Examples 1 to 5 are formed by changing the material of the scintillator primitive 1'.

[0028] The uniformity and light output intensity of each pixel in each scintillator sample in Examples 1 to 12 and Comparative Examples 1 to 5 were tested and listed in Table 1.

[0029]

[0030]

[0031] It can be seen from the above table that: setting a carbon film on the radiation surface of the scintillator can improve the uniformity and light output effect of each pixel of the scintillator, and the setting of a sharpening sheet and a crosstalk-proof metal layer can further enhance this effect.

[0032] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A scintillator with multi-level light intensity adjustment, comprising a plurality of scintillator primitives, wherein the plurality of scintillator primitives are arranged in an array structure with gaps therebetween, and each of the scintillator primitives comprises: A top surface and multiple side surfaces for receiving radiation; a reflective layer, comprising a first reflective layer covering the top surface and a second reflective layer covering the side surfaces; characterized in that: A carbon film having a wavelength matching that of the radiation is disposed between the top surface and the first reflective layer, and can coherently diffract with the radiation; the scintillator element further comprises a sharpening sheet covering the first reflective layer; the carbon film has a thickness of 0.01 to 10 nm; The sharpening sheet has a thickness of 0.2 to 1.0 mm; An anti-crosstalk metal layer is arranged between adjacent scintillator elements, and the anti-crosstalk metal layer is arranged between the second reflective layers of adjacent scintillator elements; the anti-crosstalk metal layer has a thickness of 0.1 to 0.3 mm; The scintillator element includes: scintillator crystal, scintillator glass, scintillator ceramic and plastic scintillator; the scintillator crystal includes thallium-doped sodium iodide (NaI:Tl), thallium-doped cesium iodide (CsI:Tl), bismuth germanate (Bi4Ge3O 12 , BGO), cerium-doped lutetium yttrium silicate ((Lu,Y)2SiO5:Ce, LYSO), cadmium tungstate (CdWO4, CWO), barium fluoride (BaF2), cerium-doped lanthanum chloride (LaCl3:Ce), cerium-doped lanthanum bromide (LaBr3:Ce), cerium-doped lithium yttrium hexachloride (Cs2LiYCl6:Ce, CLYC); the scintillating ceramic is a garnet structure, and its structural formula can be expressed as: (AB) 3+x C 5-x O 12 , wherein: A is a luminescent rare earth element, which is any one of Ce, Pr, Nd, Eu, Tb, Er, Dy, Tm, Ho or a combination thereof; B is any one of Sc, Y, Gd, Yb, Lu or a combination thereof; C is Al, Ga or a combination of Al and Ga; The scintillating ceramic is (Gd1-x-yPrxDy)2O2S ceramic, wherein D is any one of Ce, Pr, Eu, Nd, Sm, Gd, Ho, Yb, Tm or a combination of any two thereof.

2. The scintillator with multi-level light intensity adjustment according to claim 1, characterized in that: The anti-crosstalk metal layer is composed of one or more of W, Pt, Au, and Pb.

3. The scintillator with multi-level light intensity adjustment according to claim 1, characterized in that: The sharpening sheet is made of one or more materials selected from the group consisting of Al and Cu.

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