A bend crystal detection device and method of use thereof

Abstract

The application provides a curved crystal detection device, comprising a vacuum cavity, an X-ray source, a to-be-detected curved crystal, a first detector, a second detector, a flat crystal monochromator and a motion adjusting mechanism; an X-ray beam generated by the X-ray source is incident to the to-be-detected curved crystal; the flat crystal monochromator is used for collimating and monochromatizing a diffraction beam of the to-be-detected curved crystal; the motion adjusting mechanism is used for driving the to-be-detected curved crystal, the first detector, the second detector and the flat crystal monochromator to independently translate and / or rotate in multiple directions; the to-be-detected curved crystal, the flat crystal monochromator and the first detector are all arranged in the vacuum cavity. The application also provides a use method of the foregoing curved crystal detection device. The application provides a complete curved crystal detection device for X-ray spectrometer application, which can realize three quality detection projects of curved crystal surface shape, curved crystal focusing performance and curved crystal energy resolution, and meets the curved crystal quality detection requirements needed in actual application or research and development process.

Description

Technical Field

[0001] This invention relates to the field of X-ray detection technology, and in particular to a bent crystal detection device and its usage method. Background Technology

[0002] The curved crystal analyzer (hereinafter referred to as the curved crystal) is the core optical component of an X-ray spectrometer. Its main function is to optically focus and monochromate the incident X-rays. According to the Bragg diffraction principle, the X-ray energy is related to the interplanar spacing and the Bragg angle (i.e., the angle between the incident light and the crystal plane) as follows: 2d sinθ=nλ, where d is the interplanar spacing, θ is the Bragg angle, n is the diffraction order, and λ is the X-ray wavelength (generally, λ=12.3985 / E, where E is the X-ray energy). Therefore, when the bremsstrahlung light with a wide energy range emitted by the X-ray tube in the spectrometer is incident on a selected crystal with a fixed crystal plane, only light with a single energy corresponding to the Bragg angle will diffract, thus achieving X-ray energy monochromaticization. Since the incident light is a point source, in order to increase the receiving angle of the crystal solid and improve the diffraction efficiency, it is further physically bent to form a curved crystal similar to a concave lens, thereby focusing the incident light and improving the scanning efficiency of the spectrometer. Therefore, as a core optical component, the quality of the bent crystal directly determines the overall energy resolution and photon collection rate of the spectrometer. Insufficient energy resolution or photon collection rate will prevent X-ray spectroscopy experiments from being conducted. Furthermore, since the fabrication of bent crystals requires the physical bending of a thin planar crystal, certain bending stress exists within the bent crystal, specifically on its lattice planes. Therefore, quality inspection of the bent crystal is of great significance. To meet the spectrometer's requirements for bent crystals, the measurements should include the following three aspects: 1. Crystal plane shape of the bent crystal; 2. Focused spot size of the bent crystal; 3. Energy resolution of the bent crystal.

[0003] Currently, existing bent crystal detection devices can measure the crystal facet shape and focused spot size of bent crystals, primarily employing a near-backscattering arrangement. This is because in a type of optical path based on the Rowland circle, near-90° backscattering ensures minimal focused spot deformation, resulting in more accurate spot size and crystal facet shape parameters. When measuring the focused spot size, placing the detector on the Rowland circle yields the spot size focused from the bent crystal. When measuring the crystal facet shape, utilizing the Rowland circle imaging principle, the detector's position is offset from the Rowland circle to obtain a defocused spot, i.e., an image of the bent crystal's crystal facet shape. The intensity distribution of X-ray diffraction reflects the stress distribution within the bent crystal's internal crystal faces. However, current bent crystal detection devices are temporary installations with poor stability and repeatability, resulting in less than ideal performance, particularly in the following three aspects:

[0004] 1. It is impossible to perform intrinsic energy resolution testing on bent crystals. It is necessary to use high-energy resolution beamlines of synchrotron radiation sources at home and abroad to measure the rocking curves to obtain energy resolution values.

[0005] 2. Because air strongly absorbs X-rays with energies in the range of 3-10 keV, which is the commonly used energy range for spectrometer operation, the X-ray photon flux that ultimately reaches the detector is negligible for curved crystals with large radii of curvature, especially those with radii of curvature of 1 meter or more. This makes it impossible to perform effective focused spot size analysis and crystal facet imaging.

[0006] 3. Both the crystal bending rotary stage and the detector linear guide rail are manually operated, making it impossible to control motion accuracy. Furthermore, the detector lacks the freedom of movement perpendicular to the incident light direction, failing to meet the continuous switching requirements for crystal bending detection with different radii of curvature. In addition, frequent switching of the X-ray tube is required during actual measurements to adjust the positions of the crystal bending stage and detector, resulting in low convenience.

[0007] It is evident that there is currently no complete and comprehensive bent crystal detection device for X-ray spectrometer applications. Existing devices still have significant limitations and cannot meet the detection requirements of the core optical components of spectrometers. Summary of the Invention

[0008] To address the aforementioned shortcomings, the present invention aims to provide a bent crystal detection device for X-ray spectrometer applications, which can achieve unified and accurate measurement of the surface shape, focusing performance, and energy resolution of different types of bent crystals.

[0009] This invention provides a bent crystal detection device, comprising a vacuum cavity, an X-ray source, a bent crystal to be tested, a first detector, a second detector, a flat crystal monochromator, and a motion adjustment mechanism; the X-ray beam generated by the X-ray source is incident on the bent crystal to be tested; the flat crystal monochromator is used to collimate and monochromate the diffraction beam of the bent crystal to be tested, and includes X-ray optical devices and a flat crystal arranged sequentially along the diffraction optical axis of the bent crystal to be tested; the motion adjustment mechanism is used to drive the bent crystal to be tested, the first detector, the second detector, and the flat crystal monochromator to independently translate and / or rotate in multiple directions; the bent crystal to be tested, the first detector, the second detector, and the flat crystal monochromator are all independently translated and / or rotated in multiple directions; the X-ray beam generated by the X-ray source is incident on the bent crystal to be tested; the flat crystal monochromator is used to collimate and monochromate the diffraction beam of the bent crystal to be tested, and includes X-ray optical devices and a flat crystal arranged sequentially along the diffraction optical axis of the bent crystal to be tested; the X-ray beam generated by the X-ray source is incident on the bent crystal to be tested; the flat crystal monochromator is used to collimate and monochromate the diffraction beam of the bent crystal to be tested, and includes X-ray optical devices arranged sequentially along the diffraction optical axis of the bent crystal to be tested, the first detector, the second detector, and the flat crystal monochromator are all independently translated and / or rotated in multiple directions; the flat ... The curved crystal, the flat crystal monochromator, and the first detector are all located within the vacuum cavity. When the first detector, the X-ray source, and the curved crystal under test are located on the same circumference of a Rowland circle, the first detector acquires the focused spot image of the curved crystal under test. When the first detector moves along the diffraction axis of the curved crystal under test into the Rowland circle, the first detector acquires the crystal facet formation image of the curved crystal under test. When the flat crystal, the X-ray source, and the curved crystal under test are located on the same circumference of a Rowland circle, the flat crystal is rotated, and the second detector moves synchronously to measure the intensity of the diffraction beam of the flat crystal and acquire the rocking curve.

[0010] Preferably, the top of the vacuum chamber has a flat crystal replacement port for replacing the flat crystal monochromator and a bent crystal replacement port for replacing the bent crystal to be tested.

[0011] Preferably, the second detector is disposed outside the vacuum cavity.

[0012] Preferably, the side wall of the vacuum cavity is also provided with an outlet, through which the diffracted beam of the flat crystal can be incident on the second detector.

[0013] Preferably, the first detector is an X-ray surface detector and the second detector is an X-ray point detector.

[0014] Preferably, the motion adjustment mechanism includes a bent crystal adjustment mechanism, a first detector adjustment mechanism, a flat crystal adjustment mechanism, and a second detector adjustment mechanism. The bent crystal adjustment mechanism includes a linear displacement stage and a first rotary stage connected sequentially from bottom to top, and the bent crystal to be tested is connected to the first rotary stage. The first detector adjustment mechanism includes a first linear displacement stage and a second linear displacement stage connected sequentially from bottom to top, and the first detector is connected to the second linear displacement stage. The flat crystal adjustment mechanism includes a second rotary stage connected to the flat crystal. The second detector adjustment mechanism includes a third linear displacement stage, a fourth linear displacement stage, and a third rotary stage connected sequentially from bottom to top, and the second detector is connected to the third rotary stage.

[0015] Preferably, the X-ray source, the bent crystal to be tested, the first detector, the second detector, and the flat crystal monochromator are all located at the same height.

[0016] The present invention also provides a method of using the aforementioned bent crystal detection device, comprising the following steps:

[0017] Seal the vacuum chamber to achieve the required vacuum level.

[0018] A two-dimensional coordinate system is established with the X-ray source as the origin and the direction of movement of the bent crystal under test as the X-axis. Based on the parameters of the bent crystal under test, and combined with the required Bragg angle θ... B The operating voltage and current values ​​of the X-ray source, the radius of the Rowland circle, and the coordinates (A) of the bent crystal to be tested are determined. x , 0) and rotation angle θ1, the coordinates of the first detector on the Rowland circle (D x D y ) and the coordinates within the Rowland circle (D x ',D y '), the coordinates of the flat monochromator, the incident angle θ2 of the quasi-parallel beam on the flat crystal; so that the first detector is located on one side of the X-axis, and the flat monochromator and the second detector are located on the other side of the X-axis;

[0019] Move the bent crystal to be tested to (A) x ,0), rotate the bent crystal to be tested clockwise to move the first detector to (D x D y The X-ray source is turned on, and the diffracted beam of the bent crystal under test is focused onto the first detector. Based on the obtained focused spot image, the size of the focused spot of the bent crystal under test is detected.

[0020] Move the first detector to (D) x ',D y Based on the obtained crystal surface formation image, the X-ray intensity distribution is used to determine whether the crystal surface shape of the bent crystal under test is qualified, the internal stress distribution of the bent crystal under test is obtained, and the crystal surface shape detection of the bent crystal under test is completed.

[0021] The curved crystal under test is rotated counterclockwise so that the incident angle of the quasi-parallel beam on the crystal is θ2, and the second detector is perpendicular to the diffraction axis of the crystal. The X-ray intensity value received by the second detector at this time is recorded. The crystal is then rotated so that the incident angle of the quasi-parallel beam on the crystal changes within the range of θ2±α. The second detector moves synchronously, and the X-ray intensity value corresponding to each incident angle is obtained. The energy resolution of the curved crystal under test is further analyzed based on the rocking curve and the full width at half maximum (FWHM) value, and compared with the theoretical energy resolution to complete the energy resolution detection of the curved crystal under test.

[0022] Compared with the prior art, the beneficial effects of the present invention are:

[0023] 1. It can perform intrinsic energy resolution measurement of bent crystals: by setting up a flat crystal monochromator, a high-index plane crystal is used as a monochromator to perform monochromatic analysis on the light diffracted by the bent crystal under test;

[0024] 2. Equipped with a vacuum chamber: Eliminates the influence of air absorption, expands the detection capability of bent crystals corresponding to low-energy X-rays, and meets the detection needs of bent crystals with mainstream curvature radii of 0.5-2 meters;

[0025] 3. High-precision measurement is possible: By setting up a motion adjustment mechanism, each component has multiple degrees of freedom of movement in multiple directions. Using a linear displacement stage and a rotary stage, combined with a control system, full closed-loop control can be achieved, reaching micron-level linear motion control accuracy and micro-radian-level rotary motion control accuracy. Furthermore, the combination of linear displacement stages improves the mechanical stability and motion repeatability of the detection device, and also greatly enhances its automation and convenience.

[0026] This invention provides a complete bent crystal inspection device for X-ray spectrometer applications, which can perform three quality inspection items: bent crystal face shape, bent crystal focusing performance, and bent crystal energy resolution, thus meeting the bent crystal quality inspection needs before practical application or during research and development. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the internal structure of the bent crystal detection device of the present invention after the top of the housing is removed;

[0028] Figure 2 This is a perspective view of the crystal bending detection device of the present invention;

[0029] Figure 3 This is a schematic diagram of the connection structure between the crystal bending adjustment mechanism and the crystal to be tested.

[0030] Figure 4 This is a 3D view of the bent crystal attitude adjustment component;

[0031] Figure 5 This is a side view of the bent crystal attitude adjustment component;

[0032] Figure 6 This is a schematic diagram of the adjustment mechanism of the first detector and the connection structure of the first detector;

[0033] Figure 7 This is a schematic diagram of the connection structure of the optical flat adjustment mechanism and the optical flat monochromator;

[0034] Figure 8 This is a schematic diagram of the adjustment mechanism and connection structure of the second detector;

[0035] Figure 9 (a)-9(c) are the optical path schematic diagrams of the bent crystal detection device of the present invention.

[0036] Component designation explanation:

[0037] 1. Vacuum chamber

[0038] 11. Shell

[0039] 12. Crystal Optical Replacement Port

[0040] 13. Cube bending replacement port

[0041] 14. Incident light interface

[0042] 151 Vacuum Acquisition Equipment Interface

[0043] 152 Vacuum Penetration Interface

[0044] 153 Observation Port

[0045] 154 Vacuum Penetration Interface

[0046] 155 exit

[0047] 16 base plate

[0048] 2 X-ray sources

[0049] 31. Tested bent crystal

[0050] 32 Crystal bending clamp

[0051] 33. Curved Crystal Attitude Adjustment Component

[0052] 331 Adjustable motor

[0053] 332 Output Shaft

[0054] 333 L-type connector

[0055] 334 Spring

[0056] 335 Mounting Plate

[0057] 34 Adapter

[0058] 35 First Rotary Table

[0059] 36 Adapter

[0060] 37 Linear Displacement Stage

[0061] 41 First Detector

[0062] 42 Adapter

[0063] 43 First detector adjustment mechanism

[0064] 431 First Linear Displacement Stage

[0065] 432 Second Linear Displacement Stage

[0066] 5. Flat monochromator

[0067] 51 Flat Crystal

[0068] 52. Crystal Optic Holder

[0069] 53 Second Rotary Table

[0070] 54. Flat Crystal Support Stage

[0071] 55 X-ray optics

[0072] 551 First Slit

[0073] 552 Second Slit

[0074] 553 Slit Support Platform

[0075] 62 Adapter

[0076] 63 Second detector support platform

[0077] 64 Third Rotary Platform

[0078] 65 Second detector adjustment mechanism

[0079] 651 Third Linear Displacement Stage

[0080] 652 Fourth Linear Displacement Stage Detailed Implementation

[0081] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0082] In the description of this invention, it should be noted that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0083] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0084] Figure 2 The image shown is a perspective view of the crystal bending detection device of the present invention. In the following description, it will be referred to as... Figure 2 The attached diagram serves as a reference for direction. Figure 2 In the diagram, the height direction of the housing 11 is defined as the vertical direction (i.e., the Z-axis direction), the length direction of the housing 11 is defined as the front-back direction (i.e., the X-axis direction), and the width direction of the housing 11 is defined as the left-right direction (i.e., the Y-axis direction).

[0085] like Figure 1As shown, this invention provides a bent crystal detection device, which includes a vacuum chamber 1, an X-ray source 2, a bent crystal 31 to be tested, a first detector 41, a second detector 61, a flat monochromator 5, and a motion adjustment mechanism. The bent crystal 31 to be tested, the flat monochromator 5, and the first detector 41 are all disposed within the vacuum chamber 1. The vacuum chamber 1 can eliminate the strong absorption effect of air on X-rays, ensuring the acquisition of a focused spot image and crystal facet formation image suitable for analysis. The X-ray beam generated by the X-ray source 2 is incident on the bent crystal 31 to be tested. The flat monochromator 5 is used to collimate and monochromate the diffraction beam of the bent crystal 31 to be tested, and includes X-ray optical devices 55 and a flat crystal 51 arranged sequentially along the diffraction axis of the bent crystal 31 to be tested. The motion adjustment mechanism is used to drive the bent crystal 31 to be tested, the first detector 41, the second detector 61, and the flat monochromator 5 to independently translate in multiple directions and / or rotate around a certain direction.

[0086] Combination Figure 1 and Figure 9 The working principle of this invention is as follows:

[0087] When the first detector 41, the X-ray source 2, and the bent crystal 31 under test are located on the same circumference of the Rowland circle, the first detector 41 is located at the focal point of the Rowland circle and can acquire the focused spot image of the bent crystal 31 under test.

[0088] When the first detector 41 moves along the diffraction axis of the bent crystal 31 to the Rowland circle, it deviates from the focal point of the Rowland circle and can obtain the defocused spot image of the bent crystal 31, that is, the crystal plane formation image of the bent crystal 31. The intensity distribution of X-rays can reflect the stress distribution of the internal crystal plane of the bent crystal 31.

[0089] When the flat crystal 51, the X-ray source 2, and the curved crystal 31 to be tested are located on the same circumference of the Rowland circle, the flat crystal 51 is rotated and the second detector 61 moves synchronously to measure the intensity of the diffraction beam of the flat crystal 51 and obtain the rocking curve. The energy resolution value of the curved crystal 31 to be tested can be obtained through further analysis.

[0090] Therefore, this invention provides a comprehensive bent crystal inspection device for X-ray spectrometer applications. It can perform three-in-one quality inspection of bent crystal face shape, bent crystal focusing performance, and bent crystal energy resolution, meeting the quality inspection requirements of bent crystals, the core optical components of spectrometers, before practical application or during research and development.

[0091] Specifically, such as Figure 1 and Figure 2As shown, the housing 11 of the vacuum chamber 1 is machined with an incident light interface 14, a flat crystal replacement window 12, a bent crystal replacement window 13, a vacuum acquisition device interface 151, a vacuum penetration interface 152, an optical observation window 153, a vacuum penetration interface 154, and reserved openings for expanding other vacuum equipment needs. The X-ray source 2 is located outside the vacuum chamber 1, and its generated X-ray beam is incident on the bent crystal 31 under test through the incident light interface 14. The bent crystal 31 under test can be replaced through the bent crystal replacement window 13 located at the top of the housing 11, and the flat crystal monochromator 5 can be replaced through the flat crystal replacement window 12 located at the top of the housing 11. The wiring of the bent crystal 31 under test, the flat crystal monochromator 5, and the first detector 41 located inside the vacuum chamber 1 can be connected to a power supply or equipment located in the external atmospheric environment through the vacuum penetration interface 152 and the vacuum penetration interface 154. The vacuum pump unit extracts gas from the vacuum chamber 1 through the vacuum acquisition device interface 151 to achieve the required vacuum level. Operators can observe the operation of the equipment inside the vacuum chamber 1 through the optical observation window 153.

[0092] X-ray source 2 includes, but is not limited to, side-window / end-window / rotating target X-ray tube, liquid metal target X-ray source, laser plasma X-ray source, and synchrotron radiation X-ray source.

[0093] like Figure 1 and Figure 3 As shown, the motion adjustment mechanism includes a bending crystal adjustment mechanism, which is mounted on the base plate 16 of the vacuum chamber 1. The mechanism comprises a linear displacement stage 37, a connector 36, a first rotary stage 35, a connector 34, and a bending crystal attitude adjustment assembly 33, connected sequentially from bottom to top. The bending crystal 31 to be tested is installed in the bending crystal attitude adjustment assembly 33. The linear displacement stage 37 is arranged along the X-axis, and its slide is connected to the first rotary stage 35 via the connector 36. The linear displacement stage 37 drives the bending crystal 31 to move linearly along the X-axis, which can meet the testing requirements of bending crystals with different radii of curvature. Since the commonly used range of X-ray spectrometers is 0.25-2m, the linear displacement stage 37 of this invention uses a 2m stroke, which can meet the testing requirements of bending crystals with curvature radii within 2m. Those skilled in the art can also extend it to more than 2m as needed. The first rotary stage 35 can drive the bending crystal 31 to be tested to rotate around the Z-axis, thereby changing the Bragg angle of the X-ray beam incident on the bending crystal 31 and obtaining monochromatic light of different energies. Figure 3-5As shown, the bent crystal attitude adjustment assembly 33 includes two adjusting motors 331, an L-shaped connector 333, a mounting plate 335, and a bent crystal clamping component 32. The two adjusting motors 331 are respectively located at both ends of the L-shaped connector 333, and their output shafts 332 pass through the end of the L-shaped connector 333 and are connected to the mounting plate 335. The L-shaped connector 333 is connected to the output end of the first rotary table 35 through an adapter 34 and can rotate around the Z-axis under the drive of the first rotary table 35. A spring 334 with elastic reset function is also provided between the L-shaped connector 333 and the mounting plate 335. The bent crystal clamping component 32 includes a receiving part provided on the mounting plate 335 and a cover covering the receiving part. The bent crystal 31 to be tested is limited in the receiving part by the cover. When it is necessary to fine-tune the attitude of the bent crystal 31 to be tested, the extension amount of the output shafts 332 of the two adjusting motors 331 can be changed to make the bent crystal 31 to be tested rotate or translate, ensuring that the focused spot is emitted horizontally. The materials of the bent crystal 31 to be tested include, but are not limited to, silicon, germanium, quartz, sapphire, and lithium niobate, and the surface shape is curved, including but not limited to spheres, hyperboloids, and cylinders.

[0094] like Figure 1 and Figure 6 As shown, the motion adjustment mechanism also includes a first detector adjustment mechanism 43, which is mounted on the base plate 16 of the vacuum chamber 1. The first detector adjustment mechanism 43 includes a first linear displacement stage 431 and a second linear displacement stage 432 connected vertically from bottom to top. The first detector 41 and the second linear displacement stage 432 are connected via a transition platform 42. The first detector 41 faces the bent crystal 31 to be tested and is perpendicular to the diffraction axis of the bent crystal 31. Specifically, it is an X-ray surface detector, which can be a counting type, an integrating type, or a hybrid type. The first linear displacement stage 431 is arranged along the diffraction axis of the bent crystal 31 to be tested. During operation, it can move the first detector 41 to or away from the Rowland circle focal point, thereby acquiring a focused spot image or a crystal surface shape image. The second linear displacement stage 432 can meet the testing requirements of bent crystals with different radii of curvature. The stroke of the first linear displacement stage 431 and the second linear displacement stage 432 can be 50mm, 100mm, or 200mm.

[0095] like Figure 1 and Figure 7 As shown, in the flat monochromator 5, the X-ray optical device 55 collimates the diffracted beam of the bent crystal 31 under test, removing stray light and outputting a quasi-parallel beam. The specific form of the X-ray optical device 55 is not limited; it can be a multilayer crystal film with a parabolic shape (such as...). The device uses a mirror (such as a Montel mirror), an X-ray capillary optical lens (collimating lens), or two slits, namely a first slit 551 and a second slit 552, as employed in a specific embodiment of the invention. The specific distance between the first slit 551 and the second slit 552 is 50 mm, the slit shape is straight, and the width can be 1 mm, 3 mm, or 5 mm. The flat crystal 51 is specifically sheet-shaped, which can monochromate the diffracted beam of the curved crystal 31 to be tested. The motion adjustment mechanism also includes a flat crystal adjustment mechanism, which is mounted on the base plate 16 of the vacuum chamber 1. The flat crystal adjustment mechanism includes a flat crystal support stage 54, a second rotating stage 53 fixed on the flat crystal support stage 54, and a flat crystal clamping member 52 connected to the output end of the second rotating stage 53. The flat crystal clamping member 52 is provided with spring clips for limiting the flat crystal 51, and the flat crystal 51 is inserted into the flat crystal clamping member 52. Simultaneously, the first slit 551 and the second slit 552 are also fixed on the slit support stage 553, ensuring that the first slit 551, the second slit 552, and the flat crystal 51 are at the same height and on the same straight line. The second rotating stage 53 can drive the flat crystal 51 to rotate around the Z-axis, changing the incident angle of the quasi-parallel beam emitted from the X-ray optical device 55 on the flat crystal 51. The flat crystal monochromator 5 includes, but is not limited to, a single-crystal monochromator, a dual-crystal monochromator, and a quadruple-crystal monochromator.

[0096] like Figure 1 and Figure 8 As shown, the motion adjustment mechanism also includes a second detector adjustment mechanism 65, which is mounted on the base plate 16 of the vacuum chamber 1. The second detector adjustment mechanism 65 includes a third linear displacement stage 651, a fourth linear displacement stage 652, a third rotary stage 64, a second detector support stage 63, and a connector 62, connected sequentially from bottom to top. The second detector 61 is disposed in a groove of the connector 62. The third linear displacement stage 651 and the fourth linear displacement stage 652 are vertically connected, with the third linear displacement stage 651 positioned along the X-axis. Its travel relative to the fourth linear displacement stage 652 can be 150mm or 300mm. The third rotary stage 64 can drive the second detector 61 to rotate around the Z-axis. The second detector 61 is specifically an X-ray point detector, which can be a solid-state detector, a gas detector, or a scintillator detector. Those skilled in the art can choose to place the second detector 61 and the second detector adjustment mechanism 65 inside the vacuum chamber 1, or, as in a specific embodiment of the present invention, choose to place the second detector 61 and the second detector adjustment mechanism 65 outside the vacuum chamber 1. The latter allows for the use of a non-vacuum version of the detector, which helps reduce device costs. Furthermore, an exit port 155 is provided on the side wall of the vacuum chamber 1. The exit port 155 is made of transparent material and is hermetically connected to the side wall of the vacuum chamber 1. The diffracted beam of the flat crystal 51 can be incident on the second detector 61 through the exit port 155. In order to reduce the influence of air absorption on the X-ray beam, the second detector 61 is placed as close as possible to the exit port 155.

[0097] Both the linear displacement stage and the rotary stage described above are motor-driven and can be used with a control system to achieve fully closed-loop control. The linear motion accuracy can reach 1 micrometer, and the rotary motion accuracy can reach 10 microradians. Since the linear displacement stage and rotary stage described above are existing technologies, they will not be described in detail here.

[0098] In the bent crystal detection device of the present invention, the X-ray source 2, the bent crystal to be tested 31, the first detector 41, the second detector 61, and the flat crystal monochromator 5 are all located at the same height. This arrangement makes it convenient to use a two-dimensional coordinate system to determine the position of each component.

[0099] like Figure 1-8 As shown, the present invention also provides a method of using the aforementioned bent crystal detection device, comprising the following steps:

[0100] S1. Fix the bent crystal 31 to be tested on the bent crystal holder 32, and fix the flat crystal 51 on the flat crystal holder 52; close all windows and interfaces on the vacuum chamber 1, and evacuate the vacuum chamber 1 to a vacuum level of 0.01 mbar.

[0101] S2. Establish a two-dimensional coordinate system with X-ray source 2 as the origin and the moving direction of the bent crystal 31 to be measured (i.e., the axis of the linear displacement stage 37) as the X-axis. Input parameters such as material, surface shape, radius of curvature, and crystal plane of the bent crystal 31 to be measured into the control system. The control system, based on the input parameters and the required Bragg angle θ, will... B Determine the operating voltage and current values ​​of the X-ray source 2 required for the test, the radius of the Rowland circle, and the coordinates (A) of the bent crystal 31 to be tested. x ,0) and rotation angle θ1, the coordinates of the first detector 41 on the Rowland circle (D x D y ) and the coordinates within the Rowland circle (D x ',D y The coordinates of the flat monochromator 5 and the incident angle θ2 of the quasi-parallel beam on the flat crystal 51 are obtained. The rotation angle of the first detector 41 and the flat monochromator 5 is twice the rotation angle of the bent crystal 31 under test. Therefore, the setting direction of the first linear displacement stage 431 and the X-axis direction, and the setting direction of the flat monochromator 5 and the X-axis direction, are both at an angle of 2θ1. The Bragg angle θ of the X-ray beam on the bent crystal 31 under test is also obtained. B The value range of θ is 85-90°, and a near-backscattering arrangement is adopted to ensure minimal deformation of the focused spot, thereby obtaining accurate focused spot size and crystal plane shape parameters. In a specific embodiment of the present invention, θ B =88°, θ 1＝2°. The first detector 41 is set on the right side of the linear displacement stage 37, and the flat crystal monochromator 5 and the second detector 61 are set on the left side of the linear displacement stage 37. This arrangement can avoid mutual obstruction or interference between the components. By rotating the bent crystal 31 under test around the Z-axis, different test items of the bent crystal 31 under test can be completed.

[0102] S3, such as Figure 9 As shown in (a), the bent crystal 31 to be tested is moved to (A) x ,0) and rotate clockwise θ1 around the Z-axis so that the X-ray beam is incident on the bent crystal 31 under test at a Bragg angle of θ. B Move the first detector 41 to (D) x D y X-ray source 2 is turned on, and the X-ray beam is incident on the bent crystal 31 under test, where Bragg diffraction occurs. The diffracted beam is focused onto the first detector 41 located on the circumference of the Rowland circle. The control system detects the size of the focused spot of the bent crystal 31 under test based on the obtained focused spot image.

[0103] S4, such as Figure 9 As shown in (b), based on step S3, the first detector 41 is moved 50 mm along the diffraction axis to (D x ',D y The control system determines whether the crystal surface shape of the bent crystal 31 under test is qualified by measuring the X-ray intensity distribution based on the intensity morphology of the nearly circular defocused spot (i.e., the real image formed by the crystal surface shape of the bent crystal 31 under test), obtains the internal stress distribution of the bent crystal under test, and completes the crystal surface shape detection of the bent crystal 31 under test.

[0104] S5, such as Figure 9 As shown in (c), the bent crystal 31 to be tested is rotated counterclockwise by 2θ1 around the Z-axis so that the Bragg angle of the X-ray beam incident on the bent crystal 31 to be tested is also θ. B The optical plane 51 is adjusted so that the incident angle of the quasi-parallel beam emitted from the X-ray optical device 55 on the optical plane 51 is θ2. Then, the second detector 61 is adjusted so that it is perpendicular to the diffraction axis of the optical plane 51, and the intensity value of the received monochromatic X-ray is recorded. The optical plane 51 is rotated so that the incident angle of the quasi-parallel beam on the optical plane 51 changes within the range of θ2±α. The second detector 61 moves synchronously, maintaining its orientation perpendicular to the diffraction axis of the optical plane 51, and the intensity value of the monochromatic X-ray corresponding to each incident angle is measured to obtain the swing curve. Based on the obtained swing curve and full width at half maximum (FWHM) value, the control system further analyzes and obtains the energy resolution of the curved crystal 31 under test, and compares it with the theoretical energy resolution to complete the energy resolution detection of the curved crystal 31 under test. The aforementioned α value ranges from 1 to 3°.

[0105] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A crystal bending detection device, characterized in that, It includes a vacuum cavity, an X-ray source, a bent crystal to be tested, a first detector, a second detector, a flat crystal monochromator, and a motion adjustment mechanism; The X-ray beam generated by the X-ray source is incident on the bent crystal to be tested; The flat monochromator is used to collimate and monochromate the diffraction beam of the bent crystal under test, and includes X-ray optical devices and flat crystal arranged sequentially along the diffraction optical axis of the bent crystal under test. The motion adjustment mechanism is used to drive the bent crystal under test, the first detector, the second detector, and the flat crystal monochromator to translate and / or rotate independently in multiple directions; The bent crystal, flat crystal monochromator, and first detector under test are all located inside the vacuum cavity; When the first detector, the X-ray source, and the bent crystal under test are located on the same circumference of the Rowland circle, the first detector acquires the focused spot image of the bent crystal under test. When the first detector moves along the diffraction optical axis of the bent crystal under test into the Rowland circle, the first detector acquires a crystal plane formation image of the bent crystal under test. When the flat crystal, X-ray source, and the bent crystal under test are located on the same circumference of a Rowland circle, the flat crystal is rotated, and the second detector moves synchronously to measure the intensity of the diffraction beam of the flat crystal and obtain the rocking curve.

2. The crystal bending detection device according to claim 1, characterized in that, The top of the vacuum chamber has a flat crystal replacement port for replacing the flat monochromator and a bent crystal replacement port for replacing the bent crystal to be tested.

3. The crystal bending detection device according to claim 1, characterized in that, The second detector is located outside the vacuum chamber.

4. The crystal bending detection device according to claim 3, characterized in that, The side wall of the vacuum cavity is also provided with an exit port, through which the diffracted beam of the flat crystal can be incident on the second detector.

5. The crystal bending detection device according to claim 1, characterized in that, The first detector is an X-ray surface detector, and the second detector is an X-ray point detector.

6. The crystal bending detection device according to claim 1, characterized in that, The motion adjustment mechanism includes a bent crystal adjustment mechanism, a first detector adjustment mechanism, a flat crystal adjustment mechanism, and a second detector adjustment mechanism. The bending crystal adjustment mechanism includes a linear displacement stage and a first rotary stage connected sequentially from bottom to top, and the bending crystal to be tested is connected to the first rotary stage; The first detector adjustment mechanism includes a first linear displacement stage and a second linear displacement stage connected sequentially from bottom to top, and the first detector is connected to the second linear displacement stage; The optical flat adjustment mechanism includes a second rotary table connected to the optical flat; The second detector adjustment mechanism includes a third linear displacement stage, a fourth linear displacement stage, and a third rotary stage connected sequentially from bottom to top, and the second detector is connected to the third rotary stage.

7. The crystal bending detection device according to claim 1, characterized in that, The X-ray source, the bent crystal under test, the first detector, the second detector, and the flat monochromator are all located at the same height.

8. A method of using the crystal bending detection device as described in any one of claims 1-7, characterized in that, Includes the following steps: Seal the vacuum chamber to achieve the required vacuum level. A two-dimensional coordinate system is established with the X-ray source as the origin and the direction of movement of the bent crystal under test as the X-axis. Based on the parameters of the bent crystal under test, and combined with the required Bragg angle θ... B The operating voltage and current values ​​of the X-ray source, the radius of the Rowland circle, and the coordinates (A) of the bent crystal to be tested are determined. x , 0) and rotation angle θ1, the coordinates of the first detector on the Rowland circle (D x D y ) and coordinates within the Rowland circle (D x ',D y '), the coordinates of the flat monochromator, the incident angle θ2 of the quasi-parallel beam on the flat crystal; so that the first detector is located on one side of the X-axis, and the flat monochromator and the second detector are located on the other side of the X-axis; Move the bent crystal to be tested to (A) x ,0), rotate the bent crystal to be tested clockwise to move the first detector to (D x D y The X-ray source is turned on, and the diffracted beam of the bent crystal under test is focused onto the first detector. Based on the obtained focused spot image, the size of the focused spot of the bent crystal under test is detected. Move the first detector to (D) x ',D y Based on the obtained crystal surface formation image, the X-ray intensity distribution is used to determine whether the crystal surface shape of the bent crystal under test is qualified, the internal stress distribution of the bent crystal under test is obtained, and the crystal surface shape detection of the bent crystal under test is completed. The curved crystal under test is rotated counterclockwise so that the incident angle of the quasi-parallel beam on the crystal is θ2, and the second detector is perpendicular to the diffraction axis of the crystal. The X-ray intensity value received by the second detector at this time is recorded. The crystal is then rotated so that the incident angle of the quasi-parallel beam on the crystal changes within the range of θ2±α. The second detector moves synchronously, and the X-ray intensity value corresponding to each incident angle is obtained. The energy resolution of the curved crystal under test is further analyzed based on the rocking curve and the full width at half maximum (FWHM) value, and compared with the theoretical energy resolution to complete the energy resolution detection of the curved crystal under test.

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