Light output regulation and control method of crystal, crystal array and assembly method of crystal array

Abstract

The embodiment of the invention provides a light output regulation and control method of crystals, a crystal array and an assembling method of the crystal array. The crystal light output regulation and control method comprises the following steps: determining an initial light output value of an initial crystal; determining a target light output value of the initial crystal; on the basis of the initial light output value and the target light output value, at least one outer surface of the initial crystal is subjected to surface roughness changing machining, so that the actual light output value of the initial crystal is changed from the initial light output value to the target light output value, the surface roughness Ra of at least one outer surface of the initial crystal after the surface roughness change processing is in the range of 0.001 [mu] m to 0.1 [mu] m. The crystal array assembling method comprises the step of arranging a plurality of target crystals in an array to form a crystal array.

Description

Technical Field

[0001] The present invention relates to the field of crystal arrays, and in particular to a method for controlling the light output of a crystal, a crystal array and an assembly method thereof. Background Art

[0002] Scintillating crystals refer to crystal materials that emit visible light or ultraviolet light under the action of radiation or atomic nuclei. Scintillating crystals are widely used in nuclear medicine, such as X-ray tomography (XCT), positron emission tomography (PET), nuclear detection technology such as industrial tomography (industrial CT), oil well exploration, nuclear physics, high energy physics, environmental testing, safety testing, weapon equipment fire control, guidance and other fields.

[0003] Due to differences in the growth process and processing process of the crystal, there are differences in the light output values ​​between different individuals of the same type of scintillation crystal. Moreover, even if the growth process and processing process of the crystal are strictly restricted, there will be differences between different individuals of the same type of scintillation crystal. For example, for a crystal rod, after it is cut into multiple crystal bars, the light output values ​​of the crystal bars corresponding to the edge position of the crystal rod and the crystal bars corresponding to the middle position of the crystal rod may have a deviation of 0.02%-3.5%, and the light output values ​​of the crystal bars corresponding to the head position of the crystal rod and the crystal bars corresponding to the tail position of the crystal rod may have a greater deviation, such as 1%-10%. Therefore, in the actual use of scintillation crystals, how to regulate the light output value of scintillation crystals is a technical problem that needs to be solved urgently in this field. Summary of the invention

[0004] One or more embodiments of the present specification provide a method for controlling the light output of a crystal, the method comprising: determining an initial light output value of an initial crystal; determining a target light output value of the initial crystal; based on the initial light output value and the target light output value, processing at least one outer surface of the initial crystal to change the surface roughness so that the actual light output value of the initial crystal changes from the initial light output value to the target light output value, and the surface roughness Ra of the at least one outer surface after the surface roughness processing is changed is in the range of 0.001μm-0.1μm.

[0005] One or more embodiments of the present specification provide a light output control system for a crystal, the system comprising a controller and a processing device, the controller being configured to: obtain an initial light output value of the initial crystal; determine a target light output value of the initial crystal; the processing device being configured to: based on the initial light output value and the target light output value, perform processing to change the surface roughness of at least one outer surface of the initial crystal so that the actual light output value of the initial crystal changes from the initial light output value to the target light output value, and the surface roughness Ra of the at least one outer surface after the surface roughness processing is changed is in the range of 0.001μm-0.1μm.

[0006] One or more embodiments of the present specification provide a crystal array assembly method, the method comprising: arranging a plurality of target crystals in an array to form a crystal array; determining an initial light output value of each of the plurality of initial crystals; determining a target light output value corresponding to each of the initial crystals based on the initial light output value of each of the initial crystals; and based on the initial light output value and the target light output value, processing at least one outer surface of one or more of the plurality of initial crystals to change the surface roughness so that the actual light output value of each of the initial crystals reaches the corresponding target light output value to form the plurality of target crystals.

[0007] One or more embodiments of the present specification provide a crystal array, which is assembled by the crystal array assembly method of the above embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] This specification will be further described in the form of exemplary embodiments, which will be described in detail by the accompanying drawings. These embodiments are not restrictive, and in these embodiments, the same number represents the same structure, wherein:

[0009] Figure 1 is an exemplary flow chart of a method for controlling light output of a crystal according to some embodiments of this specification;

[0010] Figure 2 is an exemplary schematic diagram of an initial crystal according to some embodiments of the present specification;

[0011] Figure 3 is an exemplary flow chart of a crystal array assembly method according to some embodiments of this specification;

[0012] Figure 4 is an exemplary flow chart of a processing method for obtaining a plurality of target crystals for assembling a crystal array according to some embodiments of this specification;

[0013] Figure 5 is an exemplary schematic diagram of assembling multiple target crystals into a crystal array according to some embodiments of the present specification. DETAILED DESCRIPTION

[0014] In order to more clearly illustrate the technical solutions of the embodiments of this specification, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of this specification. For ordinary technicians in this field, this specification can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0015] It should be understood that the "system", "device", "unit" and / or "module" used herein are a method for distinguishing different components, elements, parts, portions or assemblies at different levels. However, if other words can achieve the same purpose, the words can be replaced by other expressions.

[0016] As shown in this specification and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "comprise" and "include" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0017] Flowcharts are used in this specification to illustrate the operations performed by the system according to the embodiments of this specification. It should be understood that the preceding or following operations are not necessarily performed precisely in order. Instead, the steps may be processed in reverse order or simultaneously. At the same time, other operations may also be added to these processes, or one or more operations may be removed from these processes.

[0018] Due to differences in the growth process and processing process of the crystal, the light output values ​​of different individuals of the same type of scintillation crystal vary. Moreover, even if the growth process and processing process of the crystal are strictly restricted, there will be differences between different individuals of the same type of scintillation crystal. The light output value is the ratio of the total number of photons emitted by the scintillator to the incident radiation energy absorbed by the scintillator. Therefore, during the use of the crystal (such as during the assembly into a crystal array), it is necessary to regulate the light output value of the scintillation crystal.

[0019] One or more embodiments of this specification disclose a method for controlling the light output of a crystal, which can process the surface roughness of the crystal, thereby controlling (increasing or decreasing) the light output of the crystal. For a detailed description of the method for controlling the light output of a crystal, see Figure 1 and its related description.

[0020] Figure 1 is an exemplary flow chart of a method for regulating light output of a crystal according to some embodiments of the present specification.

[0021] In some embodiments, process 100 may be executed by a crystal processing system or device, or by a processor of a crystal processing system or device, or by other methods. The instructions and prompts in the embodiments may be transmitted, sent, and received in various ways, including the methods described in the embodiment description, and other methods that can be thought of by those skilled in the art. Figure 1 As shown, the process 100 includes the following steps 110 to 130.

[0022] Step 110, determining an initial light output value of an initial crystal.

[0023] In some embodiments, the initial crystal may be an original crystal prepared by a crystal growth device. In some embodiments, the initial crystal may be a crystal obtained by cutting an original crystal prepared by a crystal growth device. The original crystal refers to a crystal rod or other shaped crystal raw material grown in a crystal growth device.

[0024] In some embodiments, the initial crystal is a scintillating crystal. In some embodiments, the initial crystal can be a combination of one or more crystals of various types such as cerium bromide crystals, cerium-doped lanthanum bromide crystals, cerium-doped lanthanum chloride crystals, bismuth germanate (BGO) crystals, copper bromide crystals, sodium iodide crystals, cesium iodide crystals, perovskite (CsPbBr3) crystals, silicate scintillating crystals, and garnet scintillating crystals.

[0025] In some embodiments, the initial crystal can be one or more of lutetium yttrium silicate scintillator crystal (LYSO), lutetium silicate scintillator crystal (LSO), yttrium orthosilicate scintillator crystal (YSO), and yttrium aluminum garnet crystal (YAG) doped with divalent metal ions or trivalent metal ions such as Ce (cerium), Ca (calcium), Mg (magnesium), and Sn (tin).

[0026] In some embodiments, the initial crystal is a scintillation crystal, and the initial crystal may include at least two of the elements Lu (lutetium), Si (silicon), Y (yttrium), Ca (calcium), Mg (magnesium), Al (aluminum), Ga (gallium), Sc (scandium), In (indium), La (lanthanum), Br (bromine), Ba (barium), S (sulfur), Sn (tin), Zn (zinc), Zr (zirconium), Hf (hafnium), Cd (cadmium), Pb (lead), Eu (europium), Ce (cerium), Bi (bismuth), Ge (germanium), I (iodine), Na (sodium), Cs (cesium), Cu (copper), etc. That is, the initial crystal is a scintillation crystal including at least two of the elements Lu, Si, Y, Ca, Mg, Al, Ga, Sc, In, La, Br, Ba, S, Sn, Zn, Zr, Hf, Cd, Pb, Eu, Ce, Bi, Ge, I, Na, Cs, Cu, etc.

[0027] The initial crystal may have various shapes, for example, the initial crystal may be a crystal sheet, a crystal bar, or a crystal of other shapes.

[0028] In some embodiments, before the original crystal is cut, the original crystal may be quality inspected, and the original crystal that passes the quality inspection may be cut. In some embodiments, the quality inspection includes spot inspection or full inspection of performance. As an example only, the quality inspection standard for performance may include a light output value greater than 1500 channels.

[0029] The inventors found that when preparing the original crystal, the trivalent Ce element (i.e. Ce 3+ ) and / or tetravalent Ce element (i.e. Ce 4+ ), adjust the light output value of the original crystal, and then adjust the light output value of the initial crystal. For example, when preparing the original crystal, the Ce doped in the crystal can be adjusted. 3+ and / or Ce 4+ The content of Ce can be adjusted to adjust the light output value of the original crystal. It can be understood that the luminescent center in the crystal is Ce 3+ , if Ce 3+ Low doping concentration may lead to too low activation ion concentration, fewer luminescence centers, and low luminescence intensity. 3+ Too high a doping concentration may cause concentration quenching, thereby reducing the luminous efficiency. 3+ and / or Ce 4+ Doping concentration to obtain the best luminescence effect.

[0030] Taking LYSO crystal as an example, an important physical parameter of LYSO is the luminescence yield (i.e. light output value), which is directly proportional to the Ce doped in LYSO. 3+ 、Ce 4+The ion content is directly related to the radiation. The analysis is as follows: When the radiation enters the crystal, the energy loss excites the electron transition, and then the electron transitions from the conduction band or the excitation band to the valence band to de-excite and emit photons. When the radiation enters the LYSO crystal, there is also another non-radiative de-excitation process, which is de-excitation by emitting phonons. Generally, pure crystals (i.e., crystals without other elements) have low self-absorption luminescence efficiency, so they need to be doped with some activators (such as Ce). 3+ 、Ce 4+ ions), making them the luminescence center, which can effectively prevent self-absorption and improve luminescence efficiency. Among them, the electron-hole pairs generated by ionizing radiation release energy in two ways:

[0031] Method 1: Form self-trapped excitons (STE) and then transfer the energy to the disturbed Then de-excite to emit 340nm photons, the process is as follows: Ce 3+ +e→Ce 2+ 2F - +h→(F2) -

[0032] Among them, e is electron, h is hole, F - are ions, Traps are photon capture centers in the crystal, for excited state.

[0033] Method 2: Formation of Ce-captured excitons CeTE, that is, Ce on normal lattice 3+ The excited state (Ce 3+ )*P1, de-excites to emit 300nm (286nm and 305nm) scintillation photons, the process is as follows: Ce 3+ +e+h→CeTE→Ce 3+ +hv(286nm,305nm)

[0034] Among them, e is an electron, h is a hole, and CeTE is the excited state of the Ce captured exciton.

[0035] From the way the electron-hole pairs generated by the above ionizing radiation release energy, it can be seen that the Ce doped in the crystal 3+ The content will affect the light output value of the crystal.

[0036] The luminescence behavior in LYSO crystal can be divided into the linear spectrum of fn configuration and the broadband spectrum of f→d transition. The transition in 4fn configuration is the result of the perturbation of the odd-order term of the crystal field. When Ce is excited by external light, the ground state electrons transition to the excited state and then exit the excitation process. Some energy is released in the form of photons, some energy is transferred to the surrounding crystal lattice oscillation in the form of heat energy without emitting light, and some energy is in the metastable state of the excited state. Further, the inventors found that Ce 4+ The introduction of ions makes it easier for electrons in the conduction band to be 4+ Ion capture can remove Ce from the matrix 3+ The energy level splitting caused by the crystal field effect of ions causes energy quenching due to crystal lattice defects or other impurities. 4+ Ion energy transfer to Ce 3+ The energy of the electron in the excited metastable state causes it to release a photon and form an excited state Ce 3+ , the final metastable Ce 3+ Combine with holes in the valence band to return to the ground state Ce 4+ Complete a fluorescence process; while the ground state Ce 3+ Capture holes to form transient Ce 4+ , and then the conduction band electrons combine to form excited state Ce 3+ , excited state Ce 3+ The fluorescence process is completed by radiating photons back to the ground state. 4+ Ions compared to Ce 3+ Ions can capture electrons and radiate photons faster, reducing the probability of electron trap capture. The process of capturing holes is a non-radiative process and will not cause the afterglow phenomenon of the scintillation crystal. It can effectively increase the light output of the crystal, shorten the decay time, and weaken the afterglow.

[0037] In some embodiments, when preparing the original crystal, elements such as Ca / Mg / Sn / Cl may be doped into the crystal to reduce the crystal afterglow and shorten the decay time.

[0038] The inventor has found through numerous experiments (i.e., verification tests that the adjustment of the surface roughness of the crystal leads to changes in the light output value) that the light output value of the crystal can also be related to factors such as the surface roughness of the crystal. Specifically, the light output value of the crystal is positively correlated with the surface roughness of the crystal, that is, the rougher the surface of the crystal (i.e., the greater the surface roughness), the greater the light output value of the crystal. For example, after each surface of the crystal is polished, its light output will decrease and the decay time will increase. This is because when the surface of the crystal is very smooth, it is equivalent to a plane mirror, and photons will escape through the surface, thereby reducing the number of photons emitted from the inside of the crystal, resulting in reduced brightness. At the same time, the photons reflected back may reach the end face of the crystal and be received by the photoelectric device after countless reflections inside the crystal, and the optical path becomes longer, resulting in a longer crystal light decay time. For another example, when there are different concave and convex points on the surface of the crystal, when the light is transmitted to the surface of the crystal, more photons will be reflected back to the crystal by the concave and convex points at different angles, and the photoelectric conversion device on the light output surface of the crystal will receive more photons in the same time, that is, the light output value of the crystal increases. In addition, due to the different degrees of concave and convex points on the crystal surface, light scattering will increase and the scattering angle will be larger. Surface scattering may introduce additional photon paths, prolong the propagation time of photons inside the crystal, thereby increasing the decay time, making the time for photons to be emitted from the crystal end face shorter, so the light output will decrease. For the same crystal with different surface roughness, the difference in light output ranges from 10 to 300 channels, and the difference in decay time ranges from 1 to 8 picoseconds. In other words, changes in the roughness of the crystal surface will affect the propagation and escape of photons inside the crystal, and thus affect the changes in light output and decay time.

[0039] In the verification experiment that the adjustment of the surface roughness of the crystal leads to the change of the light output value, 10 crystal bars were selected. The sizes of the 10 crystal bars are similar, and the roughness of the light output surface is not more than 0.03μm. In the verification experiment, the processing operation of changing the surface roughness of the crystal was carried out three times, and the light output value and decay time of the crystal were measured after each change of the surface roughness of the crystal, and the experimental data shown in the following Tables 1-5 were obtained. Among them, Table 1 contains the measurement data of the mean surface roughness (i.e., the mean surface roughness of each surface) and the light output value and decay time of the 10 crystal bars before processing; Table 2 contains the measurement data of the mean surface roughness and the light output value and decay time of the 10 crystal bars after the first surface roughness change, as well as the measurement data of the light output difference and decay time difference before and after the first surface roughness change; Table 3 contains the measurement data of the mean surface roughness and the mean light output value and decay time of the 10 crystal bars after the second surface roughness change, as well as the light output difference and decay time difference before and after the second surface roughness change. Table 4 contains the measurement data of the mean surface roughness, the mean light output value, and the mean decay time of the 10 crystal bars after the third surface roughness change, as well as the measurement data of the light output difference and the decay time difference before and after the third surface roughness change; Table 5 contains the measurement data of the mean surface roughness, the mean light output value, and the mean decay time of the 10 crystal bars before processing, after the first surface roughness change, after the second surface roughness change, and after the third surface roughness change, as well as the measurement data of the light output difference and the decay time difference before and after each surface roughness change.

[0040] Table 1:

[0041] Table 2:

[0042] Table 3:

[0043] Table 4:

[0044] Table 5:

[0045] It can be concluded from the measurement data in Tables 1 to 5 that when the surface roughness of the crystal bar increases, the light output of the crystal bar becomes higher and the decay time becomes lower.

[0046] In some embodiments, the initial crystal may be processed to adjust the surface roughness of the initial crystal, thereby adjusting the light output value of the initial crystal to obtain an initial crystal whose light output value meets the requirements. The processing refers to the processing of changing the surface roughness. For more information on the processing of changing the surface roughness, see step 140 and its related description.

[0047] In some embodiments, the initial crystal can be obtained by pre-treating the original crystal. Pre-treatment refers to a processing operation to adjust the size of the crystal. In some embodiments, pre-treatment may include cutting, grinding, polishing and other treatments of the original crystal. It should be noted that the grinding and polishing treatments in the process of pre-treating the original crystal are to make the cut crystal (i.e., the crystal obtained after cutting the original crystal) reach the ideal size. It is understandable that due to the low cutting accuracy, the size of the cut crystal can be fine-tuned by grinding and polishing so that the size of the cut crystal reaches the ideal size.

[0048] In some embodiments, the cutting process may be a processing operation to change the shape, size, etc. of the crystal. In some embodiments, the cutting process may include one or more of inner circle cutting, multi-wire cutting, and single-wire cutting.

[0049] In some embodiments, by cutting the original crystal, a crystal bar can be obtained as the initial crystal. The cross-sectional shape of the crystal bar perpendicular to its length direction can be rectangular or square. In some embodiments, the size range of the crystal bar can be: length (0.2mm-6mm)*width (0.2mm-6mm)*height (3mm-100mm). In some embodiments, the size of the crystal bar can also be at least one of 0.2*0.2*10mm, 0.2*0.2*50mm, 0.2*0.2*100mm, 2*2*10mm, 2*2*50mm, 2*2*100mm, 4*4*10mm, 4*4*20mm, 4*4*50mm, 4*4*100mm, etc., which can be set according to specific needs and is not limited here.

[0050] It should be noted that the cross-sectional shape of the initial crystal obtained by the above cutting process is only an exemplary description, and may also be other shapes. For example, the cross-sectional shape may be a triangle, a hexagon, an ellipse, etc. Among them, the length direction may be the axial direction of the initial crystal or the direction with the largest size among the three orthogonal directions.

[0051] In some embodiments, the grinding process can be a process of applying or pressing abrasive particles on a lap and performing a finishing process on the crystal surface by relative movement of the lap and the crystal under a certain pressure. In some embodiments, the grinding process can include one or more of single-sided grinding, double-sided grinding, etc.

[0052] In some embodiments, the polishing process may be a processing operation in which the surface of the initial crystal is processed by mechanical, chemical or electrochemical means to reduce the surface roughness of the initial crystal to obtain a bright and flat surface.

[0053] In some embodiments, taking the initial crystal as a crystal bar as an example, the crystal processing system or device can process the original crystal through the following steps S1 to S9 to obtain a bar-shaped initial crystal.

[0054] S1. Use a cutting machine to cut the crystal rod to obtain multiple crystal segments that meet the height requirements. Among them, the height deviation between any two crystal segments in the multiple crystal segments should not be greater than 0.1mm. In some embodiments, the cutting accuracy of the cutting machine can be 0.03mm-1mm. In some embodiments, when the height of the crystal segment does not meet the height requirement, the height of the crystal segment can be adjusted by grinding so that its height meets the height requirement. In some embodiments, the height requirement may include: the height of the crystal segment is within 3mm-100mm.

[0055] S2. Use a cutting machine to cut the crystal segment from the height direction of the crystal segment to obtain multiple crystal sheets that meet the thickness requirements. Among them, the thickness deviation between any two crystal sheets in the multiple crystal sheets should not be greater than 0.1mm. In some embodiments, when the thickness of the crystal sheet does not meet the thickness requirements, the thickness of the crystal sheet can be adjusted by grinding so that its thickness meets the thickness requirements. In some embodiments, the thickness requirements may include: the thickness of the crystal sheet or the adhesive sheet is within 0.2mm-6mm.

[0056] By meeting the above-mentioned height requirements and thickness requirements, a crystal sheet with a width within the range of 0.2mm-6mm and a height within the range of 3mm-100mm can be obtained.

[0057] The height requirements and thickness requirements in the above embodiments can be set according to actual production needs, and the embodiments of this specification do not limit this.

[0058] In some embodiments, the process of grinding a crystal segment or crystal sheet may include: placing the crystal segment or crystal sheet in a planetary wheel, allowing the planetary wheel to rotate with the grinding disc, the grinding disc includes an upper disc and a lower disc, and the disc surface has a sand leakage gap of 0.3mm-0.5mm, and the interval is 10mm-50mm. The upper disc and the lower disc are in a positive and negative rotation relationship, and the crystal segment or crystal sheet is double-sided ground by reversing the upper and lower discs. Among them, the mesh size of the grinding sand, the grinding speed and the grinding pressure can be determined based on experience. For example, the grinding sand is less than 500 mesh, the grinding speed is less than 30 rpm, the positive pressure of the grinding pressure is not more than 0.08MPa, and the reverse pressure is not more than 0.15MPa.

[0059] In some embodiments, the height of the crystal segment or the thickness of the crystal sheet may be measured and recorded multiple times during the grinding process until the height of the crystal segment meets the height requirement or the thickness of the crystal sheet meets the thickness requirement. For example, the height of the crystal segment or the thickness of the crystal sheet may be measured and recorded once every five grinding turns.

[0060] During the grinding process, it is necessary to observe whether the crystal segment or crystal sheet is scratched. If scratches are detected on the surface of the crystal segment or crystal sheet during the grinding process, the grinding equipment needs to be cleaned and the abrasive needs to be replaced in time.

[0061] In some embodiments, after grinding is completed, a plurality of crystal sheets whose thicknesses meet the thickness requirements can be regarded as preliminarily qualified crystal sheets, and subsequent processing steps (eg, step S3) can be performed on the preliminarily qualified crystal sheets.

[0062] In some embodiments, after grinding is completed, the surface roughness of each surface of the crystal piece can also be measured, and the crystal piece with a surface roughness of each surface not greater than 1.5 μm is selected as a preliminarily qualified crystal piece, and subsequent processing steps (for example, step S3) are performed on the preliminarily qualified crystal piece.

[0063] S3, polishing the large surface of the above-mentioned preliminary qualified crystal sheet to obtain a crystal sheet that meets the polishing requirements. The large surface refers to the two opposite surfaces with the largest area on the crystal sheet.

[0064] In some embodiments, the polishing requirement may be to make the surface roughness of the large surface of the crystal sheet no greater than 1.5 μm. The polishing requirement in the above embodiment may be set according to actual production requirements, and the embodiments of this specification do not limit this.

[0065] In some embodiments, the polishing pad material can be determined according to the polishing requirements of different materials and different precision requirements. The polishing pad material includes: polyurethane, non-woven fabrics, composite materials, epoxy resin, sulfonated polyisoprene, rayon polishing pad, wool textile polishing pad, polyurethane resin polishing pad, etc. The material selection of the polishing pad can depend on the specific requirements of the polishing process, such as physical properties such as hardness, compression ratio, retention capacity, surface roughness and density.

[0066] In some embodiments, the polishing abrasive particle size, polishing speed, polishing pressure, etc. can be set based on experience. For example, the polishing abrasive particle size is less than 10 μm, the polishing speed is less than 30 rpm, the positive polishing pressure is no more than 0.08 MPa, and the reverse polishing pressure is no more than 0.15 MPa.

[0067] In some embodiments, if scratches are detected on the surface of the crystal sheet during the polishing process, the equipment needs to be cleaned and the abrasive needs to be replaced in a timely manner.

[0068] In some embodiments, after polishing is completed, the surface roughness of the large surface of the crystal piece can also be measured, and the crystal piece with a large surface surface roughness of no more than 0.1 μm is selected as a qualified crystal piece, and the qualified crystal piece is subjected to subsequent processing steps (for example, step S4).

[0069] S4, glue multiple qualified crystal sheets and align their end faces to obtain a bonded block. During bonding, the number of qualified crystal sheets is not less than 5 and the large surface can be bonded with a protective medium. Among them, the bonded block refers to a block-shaped crystal obtained by stacking and bonding multiple qualified crystal sheets along their thickness direction.

[0070] S5, grinding and polishing the end faces of the bonding block, when the surface roughness of the end faces of the bonding block is less than 0.04 μm, a first intermediate product is obtained, and the subsequent steps (e.g., step S6) are entered. The end faces of the bonding block refer to the planes at both ends of the bonding block along its length direction.

[0071] S6. Adhere a protective glass to the end surface of the first intermediate product to obtain a second intermediate product.

[0072] S7, cutting the second intermediate product along its length direction to obtain a third intermediate product. The third intermediate product includes a plurality of crystal bars stacked and bonded together along its thickness direction or length direction.

[0073] S8. After the thickness of the third intermediate product meets the thickness requirement, the cut surface is ground to obtain a fourth intermediate product. For more information on the thickness requirement, refer to the above description.

[0074] S9, performing gelling treatment on the fourth intermediate product to obtain a plurality of crystal strips as initial crystals.

[0075] In some embodiments, the initial crystals processed by steps S1 to S9 can be used to assemble a crystal array. For example, multiple initial crystals with similar light output can be selected from a large number of initial crystals processed by steps S1 to S9 to assemble the same crystal array.

[0076] In other embodiments, the initial crystal processed by steps S1 to S9 may be further processed to adjust its light output value by changing its surface roughness, and multiple initial crystals after further processing may be assembled into a crystal array. For more information about this embodiment, see Figure 3-Figure 5 and its related description.

[0077] Figure 2 is an exemplary schematic diagram of the initial crystal shown in some embodiments of this specification.

[0078] In some embodiments, Figure 2 As shown, the outer surface of the initial crystal 200 includes a first end surface S1 and a second end surface S2 that are oppositely disposed, and a side surface located between the first end surface S1 and the second end surface S2, and at least one of the first end surface S1 and the second end surface S2 is a light emitting surface.

[0079] The end face refers to the light-emitting surface of the crystal or the surface opposite to the light-emitting surface. Figure 2 Taking the crystal bar shown in the figure as an example, the end faces of the crystal bar can be planes at both ends along the length direction. The length direction can be the axial direction of the crystal bar or the largest direction among the three orthogonal directions. Figure 2 As shown, the z direction is the axial direction of the initial crystal or the direction with the largest dimension among the three orthogonal directions.

[0080] The light-emitting surface refers to the plane from which the photons in the initial crystal are mainly emitted.

[0081] The initial light output value refers to the light output performance of the initial crystal before the initial crystal is subjected to processing operations related to light output regulation. For more information on “processing operations related to light output regulation”, please refer to step 130 and its related description.

[0082] In some embodiments, the initial light output value of the initial crystal can be detected according to the measurement method in the relevant industry standards. For example, in combination with the "GAGG Crystal and Wafer Array Performance Measurement Method", the full absorption peak method and the Compton edge method can be used for measurement. The measurement principle is: when the monoenergetic gamma radiation is incident on the scintillation detector, the distribution of its output pulse amplitude is mainly composed of spectral segments such as Compton distribution and full absorption peak (except for scintillators with low atomic numbers). The full absorption peak method and the Compton edge method use the full absorption peak or Compton distribution edge amplitude as the metric for determining the scintillator light output.

[0083] Step 120, determining a target light output value of the initial crystal.

[0084] The target light output value refers to the light output value that the initial crystal is expected to achieve after the initial crystal is processed for light output regulation.

[0085] The target light output value can be determined in a variety of ways. In some embodiments, the target light output value can be determined based on prior knowledge or by manual input. For example, the target light output value can be set and input manually based on actual production needs. In some embodiments, the light output value of a crystal can be measured by the total energy peak area corresponding to the channel data of the crystal. When high-energy particles such as X-rays (or gamma rays) interact with a crystal, the high-energy particles deposit energy in the crystal, and the atoms of the crystal enter an excited state and emit fluorescent photons when de-excited. Fluorescent photons are converted into photoelectrons by photoelectric devices (such as fluorescent photons at the PMT photocathode, which produce a photoelectric effect and are converted into photoelectrons), and then multiplied and amplified by photoelectric devices, and processed by digital-to-analog conversion to form a pulse signal. Among them, the channel is obtained by the analyzer converting the pulse signal into a number corresponding to its amplitude.

[0086] In some embodiments, the target light output value of the initial crystal can be determined based on the relevant parameters of the crystal array formed by it. Figure 3 and its related description.

[0087] Step 130, based on the initial light output value and the target light output value, at least one outer surface of the initial crystal is processed to change the surface roughness, so that the actual light output value of the initial crystal is changed from the initial light output value to the target light output value, and the surface roughness Ra of at least one outer surface after the surface roughness processing is changed is in the range of 0.001μm-0.1μm.

[0088] In some embodiments, since the light output value of the crystal is related to the surface roughness of the crystal, the processing operation related to light output regulation may include a processing operation to change the surface roughness. In some embodiments, the processing operation to change the surface roughness may include a grinding operation and / or a polishing operation. For more information about the grinding operation and the polishing operation, see step 110 and its related description.

[0089] In some embodiments, based on the initial light output value and the target light output value, one or more side surfaces, the first end surface and / or the second end surface of the initial crystal can be processed to change the surface roughness, so that the surface roughness of each side surface in the processed initial crystal is within the range of 0.01 μm-0.1 μm. When the surface roughness of any side surface in the processed initial crystal exceeds the range of 0.01 μm-0.1 μm, the influence of the surface roughness of the crystal on the propagation of photons inside the crystal can be effectively reduced to ensure the quality of the initial crystal. Preferably, the surface roughness of each side surface in the processed initial crystal can also be within one of the ranges of 0.01 μm-0.09 μm, 0.01 μm-0.08 μm, 0.01 μm-0.07 μm, 0.01 μm-0.06 μm, 0.01 μm-0.05 μm, 0.01 μm-0.04 μm, etc., to further ensure the quality of the initial crystal.

[0090] In some embodiments, one or more side surfaces, the first end face and / or the second end face of the initial crystal can also be processed to change the surface roughness based on the initial light output value and the target light output value, so that the surface roughness of each side surface in the processed initial crystal is within the range of 0.01μm-1.5μm.

[0091] When the surface roughness of any side surface of the processed initial crystal exceeds 0.01μm-1.5μm, the photon transmission inside the initial crystal will be very little affected by the crystal surface roughness, and it is meaningless to adjust the surface roughness to control the light output. In some embodiments of the present specification, by limiting the surface roughness of the side surface of the processed initial crystal, it is possible to avoid a significant impact on the photon propagation inside the initial crystal due to too large or too small surface roughness, thereby ensuring the quality of the initial crystal.

[0092] In some embodiments, the actual light output value of the initial crystal can be regulated by performing a grinding operation and / or a polishing operation on one or more side surfaces of the initial surface. In some embodiments, the change of the actual light output value of the initial crystal can be monitored during the grinding operation and / or the polishing operation, and when the actual light output value of the initial crystal reaches the target light output value, the grinding operation and / or the polishing operation is stopped. For example, the actual light output value of the initial crystal can be detected after each grinding or polishing; when the actual light output value of the initial crystal does not reach the target light output value, the grinding operation and / or the polishing operation is continued; when the actual light output value of the initial crystal reaches the target light output value, the grinding operation and / or the polishing operation is stopped.

[0093] Since the light output value of the crystal is positively correlated with the surface roughness of the crystal, in some embodiments, when the target light output value is greater than the initial light output value, processing can be performed to increase the surface roughness of one or more side surfaces of the initial crystal; when the target light output value is less than the initial light output value, processing can be performed to reduce the surface roughness of one or more side surfaces of the initial crystal.

[0094] In some embodiments, the processing operation of increasing the surface roughness may include: changing the morphology of the side surface of the initial crystal by mechanical processing such as grinding and polishing, thereby increasing the surface roughness of the side surface.

[0095] In some embodiments, the machining operation of reducing the surface roughness may include reducing the surface roughness of the side surface by ultra-precision cutting, small roughness grinding, honing, super finishing, etc. The particle size of the abrasive or the abrasive of the grinding head used is 0.1 μm-800 μm.

[0096] The above-mentioned method of increasing or decreasing the surface roughness can be carried out in any feasible manner and is not limited here.

[0097] In some embodiments, the target surface roughness of one or more side surfaces of the initial crystal can be determined according to the initial light output value of the initial crystal and the target light output value. The target surface roughness can be the surface roughness that makes the actual light output value of the initial crystal reach the target light output value.

[0098] In some embodiments, the crystal processing system or device may also determine the target surface roughness of each side surface of the initial crystal based on one or more of the target light output value of the initial crystal, the initial light output value of the initial crystal, the size of the initial crystal, the composition of the initial crystal, and the initial surface roughness of each side surface of the initial crystal, and process each side surface of the initial crystal to the target surface roughness so that the actual light output value of the initial crystal is changed from the initial light output value to the target light output value. The initial surface roughness and the target surface roughness of different side surfaces of the initial crystal may be the same or different.

[0099] The initial surface roughness refers to the surface roughness of the side surface of the initial crystal before the processing operation of light output regulation is performed on the initial crystal. The initial surface roughness can be measured and obtained by a roughness tester, a profilometer, a laser interferometer, etc.

[0100] In some embodiments, the target surface roughness can be determined in a variety of ways. For example, the target surface roughness of each side surface of the initial crystal can be determined by querying a preset table based on one or more of the target light output value of the initial crystal, the initial light output value of the initial crystal, the size of the initial crystal, the composition of the initial crystal, and the initial surface roughness of each side surface of the initial crystal. In some embodiments, the preset table includes the corresponding relationship between the target light output value of the reference crystal, the initial light output value, the size, the composition, the combination of the initial surface roughness of multiple side surfaces, and the reference surface roughness corresponding to the multiple side surfaces. Among them, the reference crystal can be a class of crystals with consistent composition and size. In some embodiments, the preset table may include the corresponding relationship between the target light output value, the initial light output value, the size, the composition, the combination of the initial surface roughness of multiple side surfaces of multiple reference crystals and the reference surface roughness corresponding to the multiple side surfaces of the reference crystal. In some embodiments, the preset table can be pre-set based on historical data or prior knowledge.

[0101] In some embodiments, the crystal processing system or device can also process the target light output value of the initial crystal, the initial light output value of the initial crystal, the size of the initial crystal, the composition of the initial crystal, and the initial surface roughness of each side surface of the initial crystal through a roughness determination model to determine the target surface roughness of each side surface of the initial crystal.

[0102] In some embodiments, the roughness determination model may be a machine learning model. In some embodiments, the roughness determination model may include any one or combination of various feasible models such as a recurrent neural network (RNN) model, a deep neural network (DNN) model, a convolutional neural network (CNN) model, etc.

[0103] In some embodiments, the roughness determination model can be trained by various methods based on multiple labeled training samples to update model parameters. For example, it can be trained based on the gradient descent method. As an example only, multiple labeled training samples can be input into the initial roughness determination model, and a loss function can be constructed by the labels and the output results of the initial roughness determination model, and the parameters of the initial roughness determination model can be iteratively updated based on the loss function. When the loss function of the initial roughness determination model meets the preset conditions, the model training is completed, and a trained roughness determination model is obtained. Among them, the preset conditions can be that the loss function converges, the number of iterations reaches a threshold, etc.

[0104] In some embodiments, the training sample may include the target light output value of the sample initial crystal, the initial light output value of the sample initial crystal, the size of the sample initial crystal, the composition of the sample initial crystal, and the initial surface roughness of each side surface of the sample initial crystal. The label corresponding to the training sample may include the target surface roughness of each side surface of the sample initial crystal. In some embodiments, the training sample can be obtained based on historical data. The label corresponding to the training sample can be obtained by manual annotation. In some embodiments, the training sample and its corresponding label can be determined based on the historical data of light output regulation of different historical initial crystals. For example, the target light output value of the historical initial crystal, the initial light output value of the historical initial crystal, the size of the historical initial crystal, the composition of the historical initial crystal, and the initial surface roughness of each side surface of the historical initial crystal in the historical data can be used as a training sample, and the target surface roughness of each side surface of the historical initial crystal in the historical data can be used as the label corresponding to the training sample.

[0105] By determining the target surface roughness of each side surface of the initial crystal through the roughness determination model, the self-learning ability of the machine learning model can be used to find patterns from a large amount of historical data, obtain the correlation between the data, and improve the accuracy and efficiency of determining the target surface roughness of each side surface of the initial crystal.

[0106] In some embodiments, after determining the target surface roughness of the initial crystal, the surface roughness of one or more side surfaces of the initial crystal can be adjusted through the aforementioned processing operation of changing the surface roughness so that the surface roughness of one or more side surfaces of the initial crystal reaches the corresponding target surface roughness.

[0107] In some embodiments, the actual surface roughness of each side surface of the initial crystal can be measured and recorded during the processing. When the actual surface roughness reaches the target surface roughness, the processing is completed to obtain the processed initial crystal.

[0108] In some embodiments of the present specification, the target surface roughness of each side surface of the initial crystal is calculated, and the actual surface roughness of each side surface of the initial crystal is made to reach the target surface roughness through processing, so that the actual light output value of the processed initial crystal is closer to the target light output value.

[0109] In some embodiments of the present specification, by processing the side surface of the initial crystal to change the surface roughness, the light output of the crystal can be effectively regulated, the reflection path of the photons can be increased, the purpose of increasing or decreasing the light output can be achieved, and the light output at different positions of the same crystal can be made uniform.

[0110] The application of scintillation crystals can be to connect a single small-sized crystal bar into a large-circle array and cooperate with a photomultiplier tube to form a scintillator detector. Scintillator detectors are widely used in nuclear medicine (positron emission tomography PET), X-ray security inspection, nuclear radiation detection, high-energy physics, space physics, environmental monitoring, geological exploration and other related fields.

[0111] When there are differences in the performance of the multiple crystal bars that make up the crystal array, or when there are differences in the processing of the multiple crystals, the light output of the multiple crystal bars that make up the crystal array will be inconsistent, reducing the consistency of the light output of the crystal array. The light output consistency of the crystal array is one of the important performance indicators of the crystal array, and the light output consistency of the crystal array will directly affect the overall performance of the crystal array. However, the light output consistency of the crystal array is affected by many factors such as the processing quality of the crystal, the defects and impurities inside the crystal, and the optical properties of the crystal. How to ensure the consistency of the light output of each crystal bar in the array is not only related to the performance of the crystal bar itself, but also has a lot to do with the crystal bar matching plate, the crystal bar assembly coupling method, the reflective medium between the crystal bars, the peripheral packaging, the light output, the silicon wafer coupling and the photomultiplier tube coupling.

[0112] One or more embodiments of this specification also disclose a crystal array assembly method, which makes the light output uniformity, energy resolution consistency and decay time consistency of a single crystal in an array better, which helps to ensure the excellent performance of the crystal array. For a detailed description of the crystal array assembly method, see Figure 3 and its related description.

[0113] Figure 3 is an exemplary flow chart of a crystal array assembly method according to some embodiments of the present specification.

[0114] In some embodiments, process 300 may be executed by a crystal assembly system or device, or by a processor of a crystal array assembly system or device, or by other methods. The instructions and prompts in the embodiments may be transmitted, sent, or received in various ways, including the methods described in the embodiment description, and other methods that may be conceived by those skilled in the art. Figure 3 As shown, process 300 includes the following steps.

[0115] Step 310, obtaining a plurality of target crystals.

[0116] The target crystal refers to a crystal material that can be used to assemble a crystal array after being processed to change the surface roughness. For example, the target crystal can be a crystal obtained by processing the initial crystal described above or below to change the surface roughness. For more information about the processing to change the surface roughness, see step 140 and its related description.

[0117] It should be noted that, since the target crystal used to form the crystal array is obtained by processing the initial crystal to change the surface roughness, the crystal type and element composition of the target crystal can be the same as those of the initial crystal.

[0118] In some embodiments, the ratio of the content of the trivalent Ce element to the tetravalent Ce element in at least two of the multiple target crystals used to form a crystal array is different. That is to say, at least two target crystals containing different ratios of the trivalent Ce element and the tetravalent Ce element can form a crystal array. It should be noted that when the content ratios of the trivalent Ce element and the tetravalent Ce element in at least two target crystals are different, in order to ensure that the light output of each target crystal in the crystal array is close (for example, the difference in light output value is within the range of (-10%, +10%), etc.), the surface roughness of at least one group of corresponding side surfaces of the at least two target crystals is different. Among them, a group of corresponding side surfaces refers to the surfaces facing the same side in the two target crystals. For more information on the content of the trivalent Ce element and the tetravalent Ce element, see Figure 1 and its related description.

[0119] In some embodiments, the difference in surface roughness Ra between any two side surfaces of any target crystal among the plurality of target crystals constituting the crystal array is less than 0.15 μm.

[0120] In some embodiments, the difference in surface roughness Ra between any two side surfaces of any target crystal in the plurality of target crystals constituting the crystal array may be less than one of 0.99 μm, 0.89 μm, 0.59 μm, 0.25 μm, 0.1 μm, 0.09 μm, 0.08 μm, 0.07 μm, 0.06 μm, 0.05 μm, 0.04 μm, 0.03 μm, 0.02 μm, 0.01 μm, 0.008 μm, 0.005 μm, 0.001 μm, etc. For more information about the side surface, see Figure 1 and its related description.

[0121] In some embodiments, the surface roughness Ra of the light output surface of any target crystal in the plurality of target crystals constituting the crystal array may be less than 0.04 μm. In some embodiments, the surface roughness Ra of the light output surface of any target crystal in the plurality of target crystals constituting the crystal array may also be less than one of 0.05 μm, 0.06 μm, 0.07 μm, 0.08 μm, 0.03 μm, 0.02 μm, 0.01 μm, etc.

[0122] In some embodiments, the surface roughness Ra of any side surface of any target crystal in the plurality of target crystals constituting the crystal array may be between 0.01 μm and 1.5 μm. In some embodiments, the surface roughness Ra of any side surface of any target crystal in the plurality of target crystals constituting the crystal array may also be between 0.01 μm and 1.4 μm, 0.01 μm and 1.3 μm, 0.01 μm and 1.2 μm, 0.01 μm and 1.1 μm, 0.01 μm and 1.0 μm, 0.01 μm and 0.9 μm, 0.01 μm and 0.8 μm, 0.01 μm and 0.7 μm, 0.01 μm and 0.6 μm, etc.

[0123] In some embodiments of the present specification, the overall light output performance of the crystal array is improved by controlling the surface roughness Ra of any two side surfaces of any target crystal among the multiple target crystals used to form the crystal array, and controlling the difference in surface roughness Ra of any two side surfaces of any target crystal among the multiple target crystals used to form the crystal array to meet certain requirements (for example, the difference is less than 0.05 μm).

[0124] In some embodiments, the difference in target light output values ​​corresponding to any two of the plurality of initial crystals used to form the crystal array is less than 10% of the target light output value of any one of the two initial crystals. Figure 1And its related description. It should be noted that when the initial crystal is processed to change the surface roughness, the goal is to make the actual light output value of the initial crystal reach the target light output value of the initial crystal. Therefore, when the initial crystal reaches the target light output value after the processing to change the surface roughness, the initial crystal that reaches the target light output value at this time can be called a target crystal. In other words, the target light output value of the initial crystal is equal to the actual light output value of the target crystal.

[0125] In some embodiments, the difference in target light output values ​​corresponding to any two of the plurality of initial crystals used to form the crystal array may be less than one of 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, etc., of the target light output value of any one of the two initial crystals. In some embodiments, the difference in target light output values ​​corresponding to any two of the plurality of initial crystals used to form the crystal array may be less than one of 15%, 14%, 13%, 12%, 11%, etc., of the target light output value of any one of the two initial crystals.

[0126] In some embodiments of the present specification, by limiting the difference in target light output values ​​corresponding to any two initial crystals to be less than a certain ratio of the target light output value of any one of the two initial crystals, the difference in target light output values ​​of multiple initial crystals constituting the same crystal array can be reduced, so that the light outputs of the multiple target crystals constituting the crystal array are close, thereby improving the light output consistency of the crystal array.

[0127] In some embodiments, multiple target crystals can be obtained by processing multiple initial crystals. Figure 4 As shown, the processing method for assembling multiple target crystals of a crystal array is described below through steps 311 to 314. Figure 4 It is an exemplary flow chart of a processing method for obtaining a plurality of target crystals for assembling a crystal array according to some embodiments of the present specification.

[0128] In some embodiments, steps 311 to 314 may be performed by a crystal assembly system or device, or by a processor of a crystal array assembly system or device, or by other methods. The instructions and prompts in the embodiments may be transmitted, sent, and received in various ways, including the methods described in the description of the embodiments, and other methods that may be conceived by those skilled in the art.

[0129] Step 311, obtaining a plurality of initial crystals.

[0130] In some embodiments, in order to obtain multiple initial crystals that can be assembled into the same crystal array, a suitable plurality of initial crystals can be selected from a large number of initial crystals. In some embodiments, the selection basis may include: the difference in initial light output values ​​of any two initial crystals among the multiple initial crystals is less than 10% of the initial light output value of any one of the two initial crystals. In other embodiments, the selection basis may include: the difference in initial light output values ​​corresponding to any two initial crystals among the multiple initial crystals is less than one of 15%, 14%, 13%, 12%, 11%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, etc., of the initial light output value of any one of the two initial crystals.

[0131] In other embodiments, the selection basis may include: selecting a plurality of initial crystals whose sizes meet the size requirements. In some embodiments, the size requirements may include: the size range of the initial crystals is length (0.2 mm-6 mm)*width (0.2 mm-6 mm)*height (3 mm-100 mm). In some embodiments, the size requirements may also include: the height difference between any two initial crystals in the plurality of initial crystals is between 3 mm and 60 mm.

[0132] Step 312, determining an initial light output value of each initial crystal in the plurality of initial crystals.

[0133] For an explanation of the initial light output values ​​of the initial crystals, see Figure 1 and its related description.

[0134] Step 313: determining a target light output value corresponding to each initial crystal based on the initial light output value of each initial crystal.

[0135] In some embodiments, the target light output values ​​of multiple initial crystals used to assemble into the same crystal array may be the same. For example, the target light output values ​​of multiple initial crystals used to assemble into the same crystal array may be set to a set target value.

[0136] In some embodiments, the set target value may be one of the median, average, mode, etc. of initial light output values ​​of a plurality of initial crystals used to assemble into the same crystal array.

[0137] In some embodiments, the set target value can be determined based on the relevant parameters of the crystal array. In some embodiments, the relevant parameters of the crystal array can include the girth of the crystal array. In some embodiments, the correspondence between different crystal array girths and different reference light output values ​​can be pre-set based on historical data or prior knowledge. When it is determined that a crystal array of a specific girth needs to be formed using multiple initial crystals, the reference light output value corresponding to the crystal array of the specific girth can be determined based on the aforementioned correspondence, and the parameter light output value is determined as the set target value.

[0138] In some embodiments, the target value may also be set manually based on actual production needs.

[0139] In some embodiments, the target light output values ​​of the multiple initial crystals used to assemble into the same crystal array may also be different.

[0140] In some embodiments, a statistical analysis can be performed based on multiple initial light output values ​​of multiple initial crystals used to assemble into the same crystal array. For example, a normal distribution diagram is constructed with the mean of multiple initial light output values ​​corresponding to the multiple initial crystals as the expected μ, three standard deviations (i.e., 3σ, σ is the standard deviation of multiple initial light output values ​​corresponding to the multiple initial crystals) as the standard, and the expected value μ is used as the midpoint of the interval to construct a preset interval (μ-3σ, μ+3σ), which can make a certain proportion (for example, 95%) of the initial light output values ​​fall into it. Further, it can be determined that the target light output value of the initial crystal whose initial light output value is within the preset interval (μ-3σ, μ+3σ) is equal to the respective initial light output value. The initial crystal whose initial light output value is within the preset interval (μ-3σ, μ+3σ) can be called a reference crystal. Further, it can be determined that the target light output value of the initial crystal whose initial light output value is outside the preset interval (μ-3σ, μ+3σ) is equal to one of the median, mean, mode, etc. of the initial light output value of one or more reference crystals.

[0141] In some embodiments, the target light output value of each initial crystal among the multiple initial crystals used to assemble into the same crystal array can be determined based on the consideration of reducing the processing time. For example, the initial crystals whose difference in initial light output values ​​corresponding to any two initial crystals among the multiple initial crystals is not less than 10% of the initial light output value of any one of the two initial crystals can be determined as the initial crystals to be processed, so as to adjust the actual light output value of this part of the initial crystals to be processed, so that the difference in initial light output values ​​corresponding to any two initial crystals to be processed among the processed initial crystals is less than 10% of the initial light output value of any one of the two initial crystals to be processed.

[0142] Step 314, based on the initial light output value and the target light output value, one or more side surfaces of one or more initial crystals among the multiple initial crystals are processed to change the surface roughness, so that the actual light output value of each initial crystal is changed from the initial light output value to the corresponding target light output value, thereby obtaining multiple target crystals.

[0143] In some embodiments, in order to improve the light output consistency of the crystal array, multiple initial crystals used to assemble into the same crystal array can be processed to change the surface roughness so that the actual light output values ​​of the multiple initial crystals used to assemble into the same crystal array reach the target light output value.

[0144] For instructions on processing to change surface roughness, see Figure 1 and its related description.

[0145] In some embodiments, when processing to change the surface roughness of multiple initial crystals used to assemble into the same crystal array, it is necessary to ensure that the verticality deviation between any two side surfaces of any target crystal among the multiple target crystals used to compose the crystal array is no more than 1 degree.

[0146] In some embodiments, when processing is performed to change the surface roughness of multiple initial crystals used to assemble into the same crystal array, it is necessary to ensure that the light output surface of any one of the multiple target crystals obtained by processing to form the crystal array can be covered with concave and convex points with an average height of no more than 0.03 μm, and other surfaces (for example, at least one side surface) can be covered with concave and convex points with an average height of no more than 1 μm.

[0147] Step 320 , arranging a plurality of target crystals in an array to form a crystal array.

[0148] A crystal array is an array composed of multiple target crystals.

[0149] like Figure 5 As shown, the target crystals a11, a12, a13, a14, a21, a22, a23, a24, a31, a32, a33, a34, a41, a42, a43, a44 can form a crystal array [(a11, a12, a13, a14), (a21, a22, a23, a24), (a31, a32, a33, a34), (a41, a42, a43, a44)].

[0150] In some embodiments, there is at least one group of target crystals in the crystal array coupled by air, and one group of target crystals includes two target crystals. In some embodiments, there is at least one group of target crystals in the crystal array coupled by a reflective film. In some embodiments, there is at least one group of target crystals in the crystal array coupled by a reflective filler. In some embodiments, multiple target crystals in the crystal array can be coupled by one or more of the above coupling methods.

[0151] In some embodiments, when at least one group of target crystals is formed by coupling, fillers may be arranged between some or all of the target crystals to separate some or all of the target crystals. The types of fillers include but are not limited to polytetrafluoroethylene (PTFE), enhanced specular reflector (ESR), E60, Teflon, barium compounds, titanium compounds, magnesium compounds, etc.

[0152] The reflective film refers to a light-proof reflective medium layer. In some embodiments, the reflective film may be present between every two target crystals. The reflective film may enhance the optical performance of the crystal array and prevent crosstalk between target crystals. In some embodiments, the reflectivity of the reflective film is greater than 92% and the thickness is less than 0.3 mm.

[0153] In some embodiments, the reflective film can be an ESR film, polytetrafluoroethylene tape, aluminum foil, white polyester reflective film, white polyacrylic reflective film, silver-coated mirror reflective film, E60 reflective film, etc.

[0154] In some embodiments, at least one layer of reflective film is required to form a crystal array. In some embodiments, the reflective film can be filled between crystal rows (or crystal columns) in the crystal array. In some embodiments, the reflective film can improve the scintillation performance of the crystal array and prevent crosstalk between crystal rows (or crystal columns).

[0155] In some embodiments, the thickness of the reflective film is no greater than 0.5 mm.

[0156] In some embodiments, the reflective filler may include a barium compound, a titanium compound, or a mixture of a barium compound and a titanium compound. Titanium compounds and barium compounds can be used as fillers for the reflective layer, and they have their own advantages and characteristics in different optical and electronic applications. When selecting a reflective filler, factors such as the wavelength range, reflective performance, transparency, mechanical strength, and environmental stability required for the reflective layer need to be considered. Different materials have different advantages and limitations, so appropriate materials can be selected according to the requirements of specific applications. A typical reflective layer is usually a multilayer structure, including a stack of multiple different materials to achieve specific reflection and transmission properties. As an example only, the barium compound can be one or more of barium sulfate (BaSO4), barium titanate (BaTiO3), barium carbonate (BaCO3), barium chloride (BaCl2), etc. The titanium compound can be one or more of titanium dioxide (TiO2), indium tin oxide (ITO, Indium Tin Oxide), titanium nitride (TiN), etc. Among them, BaSO4 has high opacity and high reflectivity in the visible and infrared spectrum ranges. TiO2 has a high refractive index and high reflectivity, especially in the ultraviolet spectrum range. Excellent performance. BaTiO3 has excellent photorefractive properties, high beam coupling gain, and can work in visible and near-infrared wavelengths. ITO is a material with transparent conductive properties, and also has good corrosion resistance and stability. TiN has high hardness, heat resistance, wear resistance, and corrosion resistance, and has high transmittance in the visible light range. Using these compounds as optical materials for reflective layer fillers can improve the reflective performance of the reflective layer, thereby effectively ensuring the light output performance of the crystal array.

[0157] In some embodiments, multiple target crystals can be partitioned and plated to obtain multiple crystal combinations. Each crystal combination can be bonded and assembled into a crystal array according to the arrangement position.

[0158] Partitioning is the process of dividing the crystals that can be assembled into the same crystal array into a single crystal combination.

[0159] In some embodiments, the partitioning includes: dividing a plurality of target crystals with similar performance into a crystal combination. In some embodiments, the performance closeness may be that the difference between the light output performance, decay time and / or energy resolution of the target crystal is less than the corresponding difference threshold. The difference threshold may be an empirical value, a manually preset value, etc. or any combination thereof.

[0160] In some embodiments, the light output performance of the target crystal may include the light energy (ie, light output value) output by the target crystal. In some embodiments, the light output performance closeness may include that the light output value difference between the plurality of target crystals is less than the corresponding difference threshold.

[0161] In some embodiments, the light output performance of the target crystal may also include the light yield of the target crystal.

[0162] In some embodiments, the light output performance being close may include the light yields of the two target crystals being close. In some embodiments, the light yield of the target crystal may be measured by the full energy peak area corresponding to the track data of the target crystal. In some embodiments, when the relative light yield difference of the two target crystals is less than the corresponding difference threshold, the light yields of the two target crystals may be considered to be close. In some embodiments, the relative light yield difference may be characterized by the difference or maximum value of the full energy peak area corresponding to the track values ​​of the two target crystals.

[0163] When high-energy particles such as X-rays (or gamma rays) interact with crystals, the high-energy particles deposit energy in the crystals, and the atoms of the crystals enter an excited state, emitting fluorescent photons when de-excited. Fluorescent photons are converted into photoelectrons by photoelectric devices (e.g., fluorescent photons produce a photoelectric effect at the PMT photocathode and are converted into photoelectrons), and then multiplied and amplified by photoelectric devices and processed by digital-to-analog conversion to form a pulse signal. The number of pulses in the pulse signal corresponds to the number of incident particles, and the pulse amplitude is proportional to the number of fluorescent photons generated by the crystal, and thus proportional to the energy deposited by the incident particles in the crystal. Therefore, the difference in the total energy peak area corresponding to the channel values ​​corresponding to the two target crystals can be used to characterize the relative light yield difference. The channel value is obtained by the analyzer converting the pulse signal into a number corresponding to its amplitude.

[0164] In some embodiments, the partitioning and matching includes: dividing multiple target crystals of similar size into a crystal combination. In some embodiments, the size close can be that the size deviation of the target crystal is less than the corresponding size deviation threshold (for example, 0.1 mm, etc.). For example, when the length deviation, width deviation, and height deviation of the multiple target crystals are respectively less than the corresponding size deviation threshold, the multiple target crystals can be considered to be similar in size.

[0165] In some embodiments, the partitioning includes: dividing a plurality of target crystals whose verticality deviations between any two faces of the target crystals are less than a verticality deviation threshold into a crystal combination. The verticality deviation threshold may be an empirical value, a manually preset value, etc., or any combination thereof.

[0166] It should be noted that when all target crystals are partitioned and matched, they can be performed based on unified test conditions.

[0167] In some embodiments of the present specification, the target crystals are partitioned and arranged according to their performance (e.g., light output performance, attenuation time, energy resolution and / or channel). Target crystals with similar light output performance, attenuation time and / or energy resolution and small channel difference can be divided into a crystal combination for subsequent assembly of the crystal array, effectively ensuring the performance similarity of each crystal in the crystal array and improving the array qualification rate.

[0168] Bonding assembly refers to the operation of arranging and combining multiple target crystals into a crystal array.

[0169] In some embodiments, the arrangement position may be determined based on the light output performance of multiple target crystals in the crystal combination.

[0170] The arrangement position refers to the placement positions of multiple target crystals in the crystal array. For example, the arrangement position of a certain target crystal may correspond to a certain position in a certain row in the crystal array.

[0171] The arrangement position can be determined in a variety of ways. In some embodiments, the processor can randomly arrange and combine multiple target crystals in a crystal combination that constitutes a crystal array to obtain the arrangement positions of multiple target crystals. In some embodiments, the processor can place multiple target crystals with consistent performance or small performance deviation in the crystal combination at the position of a crystal row, and randomly arrange and combine multiple crystal rows to obtain the arrangement positions of multiple target crystals.

[0172] In some embodiments, the bonding assembly can be performed manually or automatically by a machine.

[0173] In some embodiments, the bonding assembly method includes: bonding a plurality of target crystals to form an initial crystal array using a reflective film or a reflective filler, wherein the thickness of the reflective film or the reflective filler is less than 0.5 mm.

[0174] The initial crystal array refers to the array obtained after bonding and assembly. The initial crystal array has not undergone any post-processing operation.

[0175] As an example only, two target crystals among multiple target crystals can be bonded by using a reflective film or a reflective filler to obtain multiple first arrays, where the first array is a 1×2 array; two first arrays among multiple first arrays can be bonded by using a reflective film or a reflective filler to obtain multiple second arrays, where the second array is a 2×2 array; four second arrays among multiple second arrays can be bonded by using a reflective film or a reflective filler to obtain multiple third arrays, where the third array is a 4×4 array; four third arrays among multiple third arrays can be bonded by using a reflective film or a reflective filler to obtain a fourth array, where the fourth array is an 8×8 array; and so on to obtain an initial target array, where the initial target array is an N×N array. Where N is the circumference of the crystal array, and N is a multiple of 2. The circumference N refers to the number of target crystals contained in each row or column of the crystal array.

[0176] In some embodiments, during the assembly process, it is necessary to ensure that the thickness of each layer of the reflective structure (e.g., reflective filling material) is less than 0.5 mm, the height deviation of the end faces of any two target crystals in each end face of the initial crystal array is less than 0.5 mm, and the seam misalignment distance is less than 0.2 mm. Among them, the height deviation of the end faces of the initial crystal array refers to the height difference between the highest end face and the lowest end face in the direction perpendicular to the end faces among the end faces of the multiple target crystals constituting the initial crystal array. The highest end face and the lowest end face are the highest and lowest planes in the direction perpendicular to the end face, respectively. The seam misalignment distance refers to the deviation value of the seam between different target crystals.

[0177] In some embodiments, the bonding assembly method may further include: an arranging step of arranging multiple target crystals in a row to form a crystal row; a coating step of applying glue on the crystal row so that one side surface of the reflective film is attached to one side surface of the crystal row, and the reflective film covers each target crystal in the crystal row; and a pasting step of applying glue on the other side surface of the reflective film and pasting another crystal row on the other side surface of the reflective film.

[0178] In some embodiments, the bonding assembly method may further include: repeating the film coating step and the pasting step to form an initial crystal array. For example, repeating the film coating step and the pasting step M times may obtain an initial crystal array comprising M+1 layers of crystal rows. A crystal row refers to a structure consisting of at least two target crystals arranged in a row.

[0179] In some embodiments, after the arrangement step or the coating step, the target crystal may be subjected to one or more of the following treatments: re-cutting, grinding, polishing, etc. For example, the target crystal may be re-cut to obtain a crystal bar with a sheet structure, and the re-cut sheet crystal bar may be ground and / or polished.

[0180] In some embodiments, when assembling a crystal row, a reflective filling material may be applied to one of the sides of every two target crystals, and the sides of the two target crystals coated with the reflective filling material may be butted together to obtain multiple 1×2 arrays. Further, a reflective filling material may be applied to one of the small faces of every two 1×2 arrays, and the small faces of the two 1×2 arrays coated with the reflective filling material may be butted together in a 1×4 array structure to obtain multiple 1×8 arrays. By analogy, a 1×S crystal row may be obtained, where S is the number of target crystals contained in the crystal row.

[0181] In some embodiments, when assembling a crystal row, two target crystals can be bonded together using a reflective filling material, and then the third target crystal can be bonded to the connector of the first two target crystals using a reflective filling material, and so on, a 1×S crystal row can be obtained, where S is the number of target crystals contained in the crystal row.

[0182] In some embodiments, after obtaining the initial crystal array, the first and second surfaces of the initial crystal array may be ground and / or polished. In some embodiments, one of the end surfaces of the initial crystal array may be used as the first surface (i.e., the light-emitting surface), and the other opposite end surface may be used as the second surface (i.e., the opposite surface of the light-emitting surface). In some embodiments, the end surface of the initial crystal array may include concave points and convex points with a height difference of no more than 0.08 mm. The height difference of the concave and convex points refers to the height difference between the deepest concave point and the highest convex point.

[0183] In some embodiments, the first and second surfaces of the initial crystal array can be ground by dry grinding, or only the first surface can be ground. In some embodiments, any other feasible grinding method can also be used for grinding, which is not limited here. In some embodiments, the angle deviation between the actual angle between the first surface and / or the second surface after grinding and the preset surface is less than 1 degree, and the flatness is less than 0.05mm. Among them, the preset angle refers to the angle value expected to be achieved between the first surface and / or the second surface and the preset surface. In some embodiments, the preset surface can be a side surface adjacent to the first surface and / or the second surface. In some embodiments, the first surface and the second surface can be each other's preset surfaces, that is, the preset surface corresponding to the first surface can be the second surface, and the preset surface corresponding to the second surface can be the first surface.

[0184] In some embodiments, the first and second surfaces of the initial crystal array may be polished by single-sided wet polishing, or only the first surface may be polished. In some embodiments, any other feasible polishing method may be used for polishing, which is not limited here. In some embodiments, the angle deviation of the first surface and / or the second surface after polishing is less than 1 degree, the smoothness of the first surface after polishing is not greater than T3, and the smoothness of the second surface after polishing is not greater than T3-H.

[0185] In some embodiments, dry grinding may be used for grinding first, and then single-side wet polishing may be used for polishing.

[0186] During the assembly process, the end faces of the target crystals may not be aligned, resulting in uneven end faces of the initial crystal array and large deviations between the end faces and the side faces. By re-polishing the light-emitting surface and the opposite surface of the initial crystal array, the end face flatness and height deviation of the initial crystal array can be effectively adjusted.

[0187] In some embodiments, the side surfaces may be coated with a reflective filling material to form a reflective layer that wraps around the side surfaces of the initial crystal array; the side surfaces are the side surfaces other than the first surface and the second surface.

[0188] In some embodiments, at least one protective layer may be wrapped around the second surface and other side surfaces to obtain a crystal array.

[0189] In some embodiments, a reflective filling material may be uniformly coated on the side surface of the initial crystal array to form a reflective layer that wraps the side surface of the initial crystal array. In some embodiments, after coating, the reflective layer may be dried, polished, and processed by a right-angle tool. In some embodiments, by uniformly coating the reflective filling material, the flatness of the reflective layer may be less than a preset flatness threshold. In some embodiments, the preset flatness threshold may be 0.001 μm-0.3 mm. In some embodiments, the preset flatness threshold may be at least one of 0.001 μm-0.2 mm, 0.001 μm-0.1 mm, 0.05 mm-0.3 mm, 0.1 mm-0.3 mm, 0.15 mm-0.3 mm, 0.2 mm-0.3 mm, etc. In some embodiments, the preset flatness threshold may be one or more of 0.3 mm, 0.2 mm, 0.1 mm, etc. Among them, the right-angle tool may refer to processing the reflective layer by a right-angle tool. Exemplary right-angle tools include, but are not limited to, vises, right-angle blocks, etc.

[0190] In some embodiments, the thickness of the reflective layer is at least one of 0.01mm-1.5mm, 0.01mm-1mm, 0.01mm-0.5mm, 0.1mm-1.5mm, 0.1mm-1mm, 0.1mm-0.5mm, 0.5mm-1.5mm, 0.5mm-1mm, etc.

[0191] In some embodiments, at least one protective layer may be wrapped around the second surface and the side surface to obtain a crystal array. In some embodiments, the protective layer may be aluminum foil. Aluminum has a low light absorbance, and the aluminum foil can ensure that the crystal array has a low light absorbance, and on the other hand, ensure that the crystal array does not deform. In some embodiments, the protective layer may also be any other feasible material, which is not limited here.

[0192] It should be noted that during the entire assembly process, no foreign matter contamination visible to the naked eye should occur, and each item needs to be inspected, wiped and confirmed before use.

[0193] Some embodiments of the present specification also disclose a light output control system for a crystal, the system comprising a controller and a processing device, the controller being configured to: obtain an initial light output value of an initial crystal; wherein an outer surface of the initial crystal comprises a first end face and a second end face arranged opposite to each other, and a side surface located between the first end face and the second end face; at least one of the first end face and the second end face is a light emitting surface; determine a target light output value of the initial crystal; the processing device being configured to: based on the initial light output value and the target light output value, perform processing to change the surface roughness of one or more side surfaces, the first end face and / or the second end face of the initial crystal, so that the actual light output value of the initial crystal is changed from the initial light output value to the target light output value, and the surface roughness Ra of at least one outer surface of the initial crystal after the surface roughness is changed is in the range of 0.001μm-0.1μm. In some embodiments, the initial crystal is a scintillation crystal, and the initial crystal includes at least two of Lu, Si, Y, Ca, Mg, Al, Ga, Sc, In, La, Br, Ba, S, Sn, Zn, Zr, Hf, Cd, Pb, Eu, Ce, Bi, Ge, I, Na, Cs, and Cu. For more information, see the above related description.

[0194] Some embodiments of the present specification also disclose a crystal array.

[0195] In some embodiments, the crystal array can be assembled by the crystal array assembly method described in any of the above embodiments. Since the crystal array assembly method described in any of the above embodiments can regulate the light output of multiple initial crystals used to assemble the crystal array, the light output values ​​of any two target crystals in the crystal array assembled by the crystal array assembly method described in any of the above embodiments are close, so that the light output consistency of each crystal in the crystal array is better, and the overall light output performance of the crystal array is better.

[0196] In some embodiments, the target crystal in the crystal array contains a trivalent Ce element (i.e., Ce 3+ ) and tetravalent Ce element (i.e. Ce 4+), the ratio of the content of the trivalent Ce element to the tetravalent Ce element in at least two target crystals in the crystal array is different, and the surface roughness of at least one group of corresponding side surfaces of the two target crystals is different. For more information about the trivalent Ce element and the tetravalent Ce element, see Figure 1 and its related description.

[0197] Factors that affect light output include element content ratio and surface roughness. When the element content ratios of the two target crystals are different (for example, Ce 3+ and Ce 4+ When the content ratio of the two target crystals is different, in order to ensure close light output, the surface roughness of at least one group of corresponding side surfaces of the two target crystals is also different.

[0198] The inventors found that a certain proportion of Ce could be doped into the crystal when preparing it. 3+ and Ce 4+ , and by adjusting Ce 3+ and Ce 4+ The content ratio of Ce can effectively regulate the light output value of a single crystal. However, due to the differences in the preparation process of different crystals, for example, the preparation formula, growth method and growth equipment of different crystals are different, so when preparing different crystals, the Ce doped into them is different. 3+ and Ce 4+ In some embodiments, crystals cut from original crystals produced by a preparation process with similar preparation formula, growth method, and growth equipment can be selected for array assembly, thereby ensuring that the light output of each crystal constituting the crystal array is close, thereby improving the light output consistency of the crystal array. However, this array assembly method has great restrictions on the selected crystals.

[0199] Furthermore, after the inventors discovered that the light output value of the crystal is also related to factors such as the surface roughness of the crystal, the reflection path of the photons can be increased or reduced by adjusting the surface roughness of the side surface and / or the surface opposite to the light output surface of a single crystal, thereby achieving the purpose of increasing or reducing the light output, so that the light output consistency of each crystal in the crystal array is better and the overall light output performance of the crystal array is better.

[0200] It should be noted that the above description of the process 100 and the process 300 is only for example and explanation, and does not limit the scope of application of this specification. For those skilled in the art, various modifications and changes can be made to the process 100 and the process 300 under the guidance of this specification. However, these modifications and changes are still within the scope of this specification.

[0201] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only for example and does not constitute a limitation of this specification. Although not explicitly stated here, those skilled in the art may make various modifications, improvements and corrections to this specification. Such modifications, improvements and corrections are suggested in this specification, so such modifications, improvements and corrections still belong to the spirit and scope of the exemplary embodiments of this specification.

[0202] At the same time, this specification uses specific words to describe the embodiments of this specification. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of this specification. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures or characteristics in one or more embodiments of this specification can be appropriately combined.

[0203] In addition, unless explicitly stated in the claims, the order of the processing elements and sequences described in this specification, the use of alphanumeric characters, or the use of other names are not intended to limit the order of the processes and methods of this specification. Although the above disclosure discusses some invention embodiments that are currently considered useful through various examples, it should be understood that such details are only for illustrative purposes, and the attached claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that are consistent with the essence and scope of the embodiments of this specification. For example, although the system components described above can be implemented by hardware devices, they can also be implemented only by software solutions, such as installing the described system on an existing server or mobile device.

[0204] Similarly, it should be noted that in order to simplify the description disclosed in this specification and thus help understand one or more embodiments of the invention, in the above description of the embodiments of this specification, multiple features are sometimes combined into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the subject matter of this specification are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

[0205] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of this specification are approximate values, in specific embodiments, the setting of such numerical values ​​is as accurate as possible within the feasible range.

[0206] Each patent, patent application, patent application publication, and other materials, such as articles, books, specifications, publications, documents, etc., cited in this specification are hereby incorporated by reference in their entirety. Except for application history documents that are inconsistent with or conflicting with the contents of this specification, documents that limit the broadest scope of the claims of this specification (currently or later attached to this specification) are also excluded. It should be noted that if the descriptions, definitions, and / or use of terms in the materials attached to this specification are inconsistent or conflicting with the contents described in this specification, the descriptions, definitions, and / or use of terms in this specification shall prevail.

[0207] Finally, it should be understood that the embodiments described in this specification are only used to illustrate the principles of the embodiments of this specification. Other variations may also fall within the scope of this specification. Therefore, as an example and not a limitation, alternative configurations of the embodiments of this specification may be considered consistent with the teachings of this specification. Accordingly, the embodiments of this specification are not limited to the embodiments explicitly introduced and described in this specification.

Claims

1. A method for controlling the light output of a crystal, characterized in that: include: determining an initial light output value of an initial crystal; determining a target light output value of the initial crystal; Based on the initial light output value and the target light output value, at least one outer surface of the initial crystal is processed to change the surface roughness so that the actual light output value of the initial crystal is changed from the initial light output value to the target light output value, and the surface roughness Ra of the at least one outer surface after the surface roughness processing is changed is in the range of 0.001μm-0.1μm.

2. The method according to claim 1, characterized in that Based on the initial light output value and the target light output value, processing is performed on one or more side surfaces of the initial crystal to change the surface roughness, comprising: When the target light output value is greater than the initial light output value, performing a process of increasing the surface roughness of one or more side surfaces of the initial crystal; When the target light output value is less than the initial light output value, processing for reducing the surface roughness of one or more side surfaces of the initial crystal is performed.

3. The method according to claim 1, characterized in that Based on the initial light output value and the target light output value, processing is performed on one or more side surfaces of the initial crystal to change the surface roughness, comprising: Correspondingly determining a target surface roughness of each side surface of the initial crystal based on one or more of the target light output value, the initial light output value of the initial crystal, the size of the initial crystal, the composition of the initial crystal, and the initial surface roughness of each side surface of the initial crystal; Each side surface of the initial crystal is machined to the target surface roughness.

4. A crystal light output control system, characterized in that: Including controllers and processing equipment, The controller is configured to: Obtaining an initial light output value of the initial crystal; determining a target light output value of the initial crystal; The processing equipment is configured as follows: Based on the initial light output value and the target light output value, at least one outer surface of the initial crystal is processed to change the surface roughness so that the actual light output value of the initial crystal is changed from the initial light output value to the target light output value, and the surface roughness Ra of the at least one outer surface after the surface roughness processing is changed is in the range of 0.001μm-0.1μm.

5. The method according to claim 1, characterized in that The initial crystal is a scintillation crystal, and the initial crystal includes at least two of Lu, Si, Y, Ca, Mg, Al, Ga, Sc, In, La, Br, Ba, S, Sn, Zn, Zr, Hf, Cd, Pb, Eu, Ce, Bi, Ge, I, Na, Cs, and Cu.

6. A crystal array assembly method, characterized in that: The method comprises: Arranging a plurality of target crystals in an array to form a crystal array; wherein the processing method of the plurality of target crystals comprises: Obtaining multiple initial crystals; determining an initial light output value of each of the initial crystals in the plurality of initial crystals; Determining a target light output value corresponding to each of the initial crystals based on the initial light output value of each of the initial crystals; Based on the initial light output value and the target light output value, at least one outer surface of one or more of the multiple initial crystals is processed to change the surface roughness, so that the actual light output value of each of the initial crystals reaches the corresponding target light output value, so as to form the multiple target crystals.

7. The method according to claim 6, characterized in that The difference in surface roughness Ra between any two side surfaces of any target crystal is less than 0.15 μm.

8. The method according to claim 6, characterized in that A difference between the target light output values ​​corresponding to any two of the initial crystals is less than 10% of the target light output value of any one of the two initial crystals.

9. A crystal array, characterized in that: The crystal array is assembled by the method according to any one of claims 6-8.

10. The crystal array according to claim 9, characterized in that: The target crystals in the crystal array contain a trivalent Ce element and a tetravalent Ce element; the content ratio of the trivalent Ce element to the tetravalent Ce element in at least two of the target crystals in the crystal array is different; Furthermore, the surface roughness of at least one group of corresponding side surfaces of the two target crystals is different.

Images