Alignment evaluation system and method for multilayer nested reflector

Abstract

The invention discloses an alignment evaluation method for a multi-layer nested reflector. The method comprises the following steps: converting horizontal parallel light of a collimator into vertical parallel light after passing through a plane reflector; the bottom radial plate is adjusted to be in a horizontal state, and the pose of the CCD camera is adjusted, so that the distance between the center of a bright spot formed by a round hole of the bottom radial plate and the center of an imaging view of the CCD camera is smaller than one pixel; mounting a first layer of reflecting mirror; coarsely adjusting the height of the CCD camera to enable the CCD camera to be within the pre-estimated range of the height of the focusing surface of the reflector; finely adjusting the height of the CCD camera to enable the height difference between the focusing surface of the reflecting mirror and the imaging surface of the CCD camera to be less than 0.1 mm; the pose of the reflector is adjusted, so that the distance between the mass center of the focusing spot of the reflector and the center of the imaging view of the CCD camera is smaller than one pixel, and the difference between the HPD of the focusing spot and the estimated value is smaller than 1 ''; and repeating the steps until the n layers of reflectors are assembled and adjusted. According to the method, the alignment condition and the focusing effect in the adjustment process of the multi-layer nested reflector can be evaluated, feedback is provided for a control system, and the adjustment alignment precision of the multi-layer nested reflector is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of precision assembly and adjustment of X-ray optical devices, and in particular relates to an alignment evaluation system and method for multi-layer nested reflectors. Background Art

[0002] The grazing-incidence X-ray focusing mirror is the core component of the X-ray astronomical observation payload, which is used to converge and collect X-rays in the universe. The Wolter-I multilayer nested reflector is a type of grazing-incidence X-ray focusing mirror, which can reflect grazing-incidence X-rays to the focal plane. It has high focusing efficiency and strong imaging detection capabilities. In the past few decades, it has received extensive attention and research internationally. However, domestic research on X-ray reflectors is still in its infancy, and the development of domestic X-ray reflectors is mainly limited to alignment and energy focusing. Since the thickness of the reflector is less than 1 mm and the number of nested layers is large, this greatly increases the difficulty of center alignment during the installation of the multilayer nested reflector, and ultimately makes it difficult to ensure the energy focusing effect of the X-ray focusing mirror. Summary of the invention

[0003] The purpose of the present invention is to overcome the above-mentioned defects and provide an alignment evaluation system and method for multi-layer nested reflectors, which solves the technical problem that the alignment of multi-layer nested reflectors is difficult during installation and adjustment. The present invention can evaluate the alignment and energy focusing effect of multi-layer nested reflectors during installation and adjustment, and give corresponding feedback to the control system, thereby ultimately improving the installation and alignment accuracy of multi-layer nested reflectors.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] An alignment evaluation system for a multi-layer nested reflector includes a collimator, a plane reflector, a bottom spoke, a CCD camera, a five-axis translation stage, a vertical rod and a slider;

[0006] The vertical rod is arranged along the vertical direction;

[0007] The CCD camera is mounted on a five-axis translation stage, which is mounted on a vertical rod through a slider. The five-axis translation stage is used to fine-tune the position of the CCD camera. The slider is used to adjust the height of the CCD camera when sliding along the vertical rod.

[0008] The bottom spoke is arranged below the CCD camera, and a plurality of annular grooves are arranged on the bottom spoke for carrying the X-ray reflector;

[0009] The horizontal parallel light emitted by the collimator is reflected by the plane reflector to form vertical parallel light, and the vertical parallel light passes through the bottom radian or the bottom radian and the X-ray reflector to form an image on the CCD camera.

[0010] Further, an alignment mark is provided on the bottom spoke;

[0011] The alignment mark is a circular through hole, and the coaxiality between the circular through hole and the annular groove is better than 0.01 mm;

[0012] The vertical parallel light passes through the alignment mark of the bottom spoke plate and forms a circular bright spot on the CCD camera. The position of the bottom spoke plate when the center of the circular bright spot coincides with the center of the imaging field of the CCD camera is taken as the reference position.

[0013] Furthermore, it also includes an X-ray reflector posture adjustment mechanism;

[0014] The X-ray reflector posture adjustment mechanism is used to adjust the posture of each layer of X-ray reflectors to complete the installation and adjustment of each layer of X-ray reflectors.

[0015] Further, the X-ray reflector posture adjustment mechanism includes a plurality of ropes;

[0016] One end of each rope is connected to a plurality of small holes evenly distributed in the circumferential direction of the upper end of the X-ray reflector, and the other end is connected to a drive motor. The drive motor adjusts the position of the X-ray reflector by driving each rope.

[0017] A method for evaluating the alignment of a multi-layer nested reflector is implemented by using the above-mentioned system for evaluating the alignment of a multi-layer nested reflector, comprising:

[0018] S1 converts the horizontal parallel light emitted by the collimator into vertical parallel light after passing through the plane reflector;

[0019] S2 installs a bottom radiator plate on the optical path of vertical parallel light, and installs a CCD camera above the bottom radiator plate;

[0020] Adjust the bottom radial plate to a horizontal state, and adjust the position of the CCD camera so that the center of the circular bright spot formed by the parallel light passing through the bottom radial plate on the CCD camera coincides with the center of the imaging field of the CCD camera;

[0021] S3 installs the first layer (innermost layer) of X-ray reflectors on the bottom diaphragm;

[0022] The height of the CCD camera is adjusted by sliding the slider up and down along the vertical rod so that the CCD camera is located within the estimated range of the height of the X-ray reflector focal plane;

[0023] S4 fine-tunes the up and down position of the CCD camera through a five-axis translation stage so that the focusing plane of the first-layer X-ray reflector coincides with the imaging plane of the CCD camera;

[0024] S5 adjusts the posture of the first layer of X-ray reflectors so that the centroid of the focused spot of the first layer of X-ray reflectors coincides with the center of the imaging field of the CCD camera, and the half-energy diameter HPD of the focused spot is within the estimated range;

[0025] S6: bonding and fixing the first layer of X-ray reflectors to the corresponding annular grooves on the bottom radiator plate, thereby completing the installation and adjustment of the first layer of X-ray reflectors;

[0026] S7 installs the i-th layer of reflectors on the bottom radial plate, 2≤i≤n, n is the total number of reflectors;

[0027] S8 adjusts the posture of the i-th layer X-ray reflector so that the centroid of the focused light spot of the i-th layer X-ray reflector coincides with the center of the imaging field of the CCD camera, and the half-energy diameter HPD of the focused light spot is within the estimated range;

[0028] S9: adhesively fix the i-th layer X-ray reflector to the corresponding annular groove on the bottom radiator plate, completing the installation and adjustment of the i-th layer X-ray reflector;

[0029] S10: Repeat steps S7 to S9 to adjust each layer of X-ray reflectors until n layers of X-ray reflectors are adjusted.

[0030] Furthermore, in step S2, a rectangular coordinate system is established with the center of the imaging field of the CCD camera as the coordinate origin;

[0031] Obtaining the deviation of the center of the circular bright spot from the coordinate origin in the X direction and the Y direction according to the coordinate of the center of the circular bright spot in the coordinate system;

[0032] The five-axis translation stage fine-tunes the position of the CCD camera according to the deviation between the center of the circular bright spot and the coordinate origin in the X direction and the Y direction, until the center of the circular bright spot coincides with the center of the imaging field of the CCD camera;

[0033] The standard for the center of the circular bright spot to coincide with the center of the imaging field of the CCD camera is that the distance between the center of the circular bright spot and the center of the imaging field of the CCD camera is less than 1 pixel.

[0034] Furthermore, in step S3, when the CCD camera is located within the estimated range of the height of the focal plane of the X-ray reflector, the estimated range is d±5 mm, where d is the focal length of the X-ray reflector.

[0035] Furthermore, in step S4, the criterion for making the focusing plane of the first layer of X-ray reflectors coincide with the imaging plane of the CCD camera is that the height difference between the focusing plane of the first layer of X-ray reflectors and the imaging plane of the CCD camera is less than 0.1 mm.

[0036] Further, in step S5 or step S8, the deviation of the centroid and the coordinate origin in the X direction and the Y direction are obtained according to the coordinates of the centroid of the focused light spot of the first layer or the i-th layer of the X-ray reflector in the coordinate system;

[0037] Adjust the position of the first or i-th layer of X-ray reflectors according to the deviation between the center of mass and the origin of the coordinates in the X direction and the deviation in the Y direction until the center of mass of the focused spot of the X-ray reflector coincides with the center of the imaging field of the CCD camera, and the half-energy diameter HPD of the focused spot is within the estimated range; the difference with the estimated value is less than 1″;

[0038] The criterion for the centroid of the X-ray reflector focused spot to coincide with the center of the CCD camera imaging field of view is: the distance between the centroid of the X-ray reflector focused spot and the center of the CCD camera imaging field of view is less than 1 pixel;

[0039] The standard for the half-energy diameter HPD of the focused spot to be within the estimated range is that the difference between the half-energy diameter HPD of the focused spot and the estimated value is less than 1″. The estimated value is obtained by testing the surface data of the X-ray reflector and then performing optical simulation calculation on the surface data. The value is generally <10″.

[0040] Furthermore, when the second to nth layers of X-ray reflectors are adjusted, an aperture is added to the X-ray reflectors of the previous layer that have been adjusted.

[0041] Or, when adjusting the 2nd to nth layers of X-ray reflectors, the distance between the centroid of the focused light spot obtained by superimposing the X-ray reflectors of this layer and the previous layers and the center of the imaging field of the CCD camera is less than 1 pixel, and the half-energy diameter (HPD) of the focused light spot is within the estimated range.

[0042] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0043] (1) The present invention creatively provides an alignment evaluation method for a multi-layer nested reflector, which can evaluate the alignment status and energy focusing effect of the multi-layer nested reflector during the installation and adjustment process, and give corresponding feedback to the control system, thereby ultimately improving the installation and alignment accuracy of the multi-layer nested reflector;

[0044] (2) The present invention determines the initial reference in the reflector adjustment process before adjusting the reflector, laying a foundation for the subsequent adjustment of each layer of reflectors, and effectively improving the efficiency of the reflector adjustment;

[0045] (3) The CCD camera in the present invention can be moved up and down within a relatively large height range, thereby ensuring that the focusing spot imaging can be performed on reflectors of different focal lengths, and the operation is simple and the adaptability is strong. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is a principle schematic diagram of an alignment evaluation system for multi-layer nested reflectors of the present invention;

[0047] Figure 2 This is a core structural diagram of an alignment evaluation system for multi-layer nested reflectors of the present invention;

[0048] Figure 3 A schematic diagram of the light spot evaluation of the CCD camera imaging of the present invention;

[0049] Figure 4 A schematic diagram of the alignment mark provided on the bottom spoke of the present invention;

[0050] Among them, 1- parallel light tube, 2- plane mirror, 3- bottom spoke, 4- X-ray mirror, 5- CCD camera, 6- five-axis translation stage, 7- vertical rod, 8- slider, 9- centroid of focused spot, 10- half energy diameter (HPD) value, 11- X direction deviation, 12- Y direction deviation, 13- alignment mark. DETAILED DESCRIPTION

[0051] The following detailed description of the present invention will make the features and advantages of the present invention more clear and explicit.

[0052] The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. Although various aspects of the embodiments are shown in the drawings, the drawings are not necessarily drawn to scale unless otherwise noted.

[0053] In order to ensure the alignment and energy focusing effect of the multi-layer nested reflector during installation and adjustment, the present invention provides an alignment evaluation method for the multi-layer nested reflector. The method can evaluate the alignment and energy focusing effect of the multi-layer nested reflector during the installation and adjustment process, calculate the alignment deviation, and give corresponding feedback information to the control system to adjust the installation posture of the multi-layer nested reflector until the required accuracy requirements are met.

[0054] The present invention discloses an alignment evaluation system for a multi-layer nested reflector, comprising a collimator, a plane reflector, a bottom radial plate, a CCD camera, a CCD camera posture adjustment mechanism, and a CCD camera height adjustment mechanism, wherein an alignment mark is provided on the bottom radial plate. The CCD camera posture adjustment mechanism is implemented by a five-axis displacement stage and is used to fine-tune the posture of the CCD camera; the CCD camera height adjustment mechanism is composed of a vertical rod and a slider and is mainly used to adjust the height of the CCD camera within a relatively large range to meet the imaging requirements of reflectors with different focal length specifications; the alignment mark on the bottom radial plate is essentially a precisely machined circular through hole, which is used to ensure that the geometric center of the field of view of the CCD camera coincides with the geometric center axis of the radial plate before the first layer of reflectors are installed and adjusted, so as to serve as the initial reference for the installation and adjustment.

[0055] The present invention discloses an alignment evaluation method for a multi-layer nested reflector, comprising the following steps: aligning a CCD camera with an alignment mark of a spoke plate at the bottom of an X-ray reflector, overlapping a focusing surface of the X-ray reflector with an imaging surface of the CCD camera, center positioning of a focusing spot of a single-layer and a multi-layer reflector, calculating a center deviation, and calculating a half-energy diameter (HPD) value of the focusing spot.

[0056] In order to ensure that the parallel light is accurately focused on the imaging surface of the CCD camera after passing through the X-ray reflector, the CCD camera is fixed on a five-axis translation stage, and the position of the five-axis translation stage is adjusted to make the imaging surface of the CCD camera coincide with the focusing surface of the reflector.

[0057] In order to enable reflectors of various focal lengths to be imaged on a CCD camera, the five-axis translation stage is fixed to a slider that can slide along a vertical rod in a large range. The slider can drive the CCD camera to move up and down in a large range, thereby adapting to reflectors of different focal lengths so that they can all be focused and imaged on the CCD camera.

[0058] Parallel light is emitted by a horizontally placed collimator and then passes through a precisely adjustable 45-degree plane reflector to convert the horizontal parallel light into vertical parallel light, so that the parallel light passes through the X-ray reflector and is finally focused and imaged on the CCD camera.

[0059] The five-axis translation stage is mainly used to adjust the position of the CCD camera, including three translations and two rotations, excluding the rotation around the X-ray reflector axis. The five-axis translation stage is used to precisely adjust the position of the CCD camera so that the geometric center of the CCD camera coincides with the geometric center axis of the alignment mark on the bottom spoke, and the imaging surface of the CCD camera is finely adjusted to coincide with the focusing surface of the X-ray reflector.

[0060] The bottom spoke is located at the bottom of the multi-layer nested reflectors and has an alignment mark at its geometric center. The alignment mark on the bottom spoke is essentially a precision-machined circular through hole, which is used to allow parallel light to pass through the alignment mark before adjusting the first layer of reflectors so that the image generated is located at the center of the CCD camera's field of view, thereby ensuring that the geometric center of the CCD camera coincides with the geometric center axis of the bottom spoke.

[0061] The center positioning of the focused light spot refers to the center of mass (intensity center) of the focused light spot. The center deviation is the position deviation between the center of mass of the focused light spot and the center of the field of view of the CCD camera. There are two cases for the center of mass of the focused light spot:

[0062] 1) Only consider the light spot generated by a single-layer reflector on the CCD camera;

[0063] 2) Consider the light spot generated by the multi-layer reflector, that is, the centroid of the light spot generated on the CCD camera after multiple focused light spots are superimposed.

[0064] The half-energy diameter (HPD) of the focused spot means: with the center of mass of the focused spot as the center of the circle and half of the focused spot energy in the entire CCD field of view as the target, a circle is drawn. The diameter of the circle is the HPD value. The spot energy in this circle is half of the focused spot energy in the entire CCD field of view.

[0065] The present invention performs center positioning on the imaging of light through a reflector on a CCD camera, and calculates the half-energy diameter (HPD) of the light spot. Finally, the alignment and energy focusing effect of the reflector are evaluated through the center coordinates and the half-energy diameter (HPD) value, and then the calculation results are fed back to the control system, thereby adjusting the position of the reflector until the calculation results meet the requirements.

[0066] The present invention fixes a CCD camera on a five-axis translation stage. By adjusting the five-axis translation stage, the focusing plane of the reflector is located on the imaging plane of the CCD camera at a certain accuracy level, and the center of the field of view of the CCD camera coincides with the geometric center axis of the bottom spoke of the X-ray reflector, thereby ensuring the initial reference during the reflector assembly and adjustment process.

[0067] The invention fixes a five-axis translation stage with a CCD camera on a slider that can slide up and down along a vertical rod, so that the CCD camera can move up and down within a relatively large height range, thereby ensuring that focusing spot imaging can be performed on reflectors of different focal length models.

[0068] Example:

[0069] like Figure 1 , Figure 2 , Figure 3As shown, an alignment evaluation system for a multi-layer nested reflector includes: a collimator 1, a plane reflector 2, a bottom spoke 3, a CCD camera 5, a five-axis displacement stage 6, a vertical rod 7, a slider 8, and an alignment mark 13 on the bottom spoke 3. The five-axis displacement stage 6 is fixed to the slider 8 that can slide along the vertical rod 7. When in use, the CCD camera 5 is driven to achieve a large range of height adjustment by sliding the slider 8 up and down, so that reflectors with different focal lengths can be imaged on the CCD camera 5; the CCD camera 5 is fixed on the five-axis displacement stage 6, and the posture of the CCD camera 5 is adjusted by precisely adjusting the posture of the five-axis displacement stage 6 to ensure that the imaging surface of the CCD camera 5 coincides with the focusing surface of the reflector; the bottom spoke 3 is located at the bottom of the multi-layer nested reflector, and contains a precisely machined circular through hole in its center as an alignment mark 13, which is used to ensure that the geometric center of the CCD camera coincides with the geometric center axis of the bottom spoke; the center positioning of the spot and the half-energy diameter (HPD) value of the spot are fed back to the control system after the imaging calculation of the CCD camera.

[0070] like Figure 3 As shown, the present invention calculates the light spot imaged by the reflector on the CCD camera 5 to obtain the position of the center of mass 9 of the focused light spot, the X-direction deviation 11 and Y-direction deviation 12 of the center of mass 9 of the focused light spot relative to the center of the field of view of the CCD camera 5, and the half-energy diameter (HPD) value 10 of the light spot.

[0071] The present invention provides an alignment evaluation method for multi-layer nested reflectors, and the steps are as follows:

[0072] Step 1: Open the collimator 1, make the horizontal parallel light incident on the plane reflector 2, and then adjust the plane reflector 2 so that the parallel light is converted into vertical parallel light after passing through the plane reflector 2. In the adjustment test of this method, the parallel light can be visible light or ultraviolet light. The plane reflector 2 is preferably a 45° plane reflector.

[0073] Step 2: Before starting to adjust the X-ray reflector 4, adjust the bottom spoke 3 of the X-ray reflector 4 to a horizontal state and fix it, and fix the CCD camera 5 to the five-axis translation stage 6, and then fix the five-axis translation stage 6 with the CCD camera 5 fixed to the slider 8. The position of the bottom spoke 3 has been determined after this step. For the field of view of the CCD camera 5, a rectangular coordinate system is established with the center point of the field of view as the origin of the coordinates, so as to determine the position of the point within the field of view of the CCD camera 5, the centroid 9 of the focused light spot, the X-direction deviation 11 of the center position of the focused light spot, and the Y-direction deviation 12.

[0074] like Figure 4Since the position of the bottom spoke 3 is fixed at this time, the vertical parallel light passes through the alignment mark 13 on the bottom spoke, and will be imaged as a circular bright spot on the CCD camera 5. Then the coordinates and deviation of the center of the bright spot in the field of view of the CCD camera 5 are identified and calculated. The position of the CCD camera 5 is adjusted by adjusting the five-axis translation stage 6, so that the distance between the center of the circular bright spot and the center of the imaging field of the CCD camera 5 is less than 1 pixel. The CCD camera 5 at this time is used as the centering reference for the subsequent adjustment of the reflector.

[0075] Step 3: Multi-layer nested reflectors There are reflectors with various focal lengths. According to the reflectors with different focal lengths, the height between the CCD camera 5 and the X-ray reflector 4 needs to be adjusted. Therefore, before adjustment, the focal length value of the currently adjusted X-ray reflector 4 is first determined. Taking the reflector with a focal length of 4.5m as an example, the height of the CCD camera 5 is roughly adjusted by adjusting the slider 8 up and down, so that the CCD camera 5 is located within a certain range of the focal plane height of the X-ray reflector 4 (at a height within the range of 4500±5mm). At this time, the focused spot image formed by the parallel light passing through the X-ray reflector 4 can be clearly presented on the CCD camera 5, and then the fourth step can be performed.

[0076] Step 4: Start to adjust the first layer of X-ray reflector 4. At this time, the focusing spot of the first layer of X-ray reflector 4 has appeared on the CCD camera 5. Then, by fine-tuning the height of the five-axis translation stage 6 along the optical axis, the imaging surface of the CCD camera 5 is precisely adjusted in the axial direction, so that the height difference between the focusing surface of the X-ray reflector 4 and the imaging surface of the CCD camera 5 is less than 0.1mm. The focusing surface position (i.e., focal length) of the X-ray reflector 4 has been measured before adjustment, and the measurement accuracy is better than 10μm.

[0077] Step 5: During the adjustment of the first layer of X-ray reflector 4, after the focused spot image presented on the CCD camera 5 is obtained, the position of the centroid 9 of the focused spot on the CCD camera 5, the X-direction deviation 11, the Y-direction deviation 12 and the half-energy diameter (HPD) value 10 are continuously calculated, and then transmitted to the control system as a reference to continuously adjust the posture of the X-ray reflector 4. In this process, the posture of the X-ray reflector 4 is adjusted once each time the focused spot on the CCD camera 5 is calculated, until the distance between the centroid 9 of the focused spot and the center of the CCD camera 5 is less than 1 pixel, and the half-energy diameter (HPD) value 10 that differs from the estimated value by less than 1″ is obtained, it can be considered that the adjustment of the first layer of X-ray reflector 4 is completed.

[0078] The center of mass of the light spot is calculated by calculating the intensity value of the pixel points within the field of view of the CCD camera, and the center of mass of the light spot is obtained; the half-energy center diameter (HPD) value of the light spot refers to the circle with the center of mass of the light spot as the center and the HPD value as the diameter on the current CCD light spot image, so that the energy value inside the circle is half of the total energy value. The deviation between the center of mass of the light spot and the center of the CCD camera and the half-energy diameter (HPD) value can be used to evaluate the alignment and focusing effect of the reflector, and feedback can be given to the control system to adjust the reflector posture.

[0079] Step 6: Glue and fix the adjusted reflector to the corresponding annular groove on the bottom radiator. When adjusting the other layers of X-ray reflectors 4 after the first layer, the influence of the focus spot of the previously adjusted reflectors needs to be considered. There are two execution schemes for processing the focus spots of these reflectors:

[0080] (1) Add apertures to the previously adjusted X-ray reflectors 4 to prevent parallel light from entering these X-ray reflectors 4 and generating focused light spots on the CCD camera 5. At this time, only the focused light spots generated by the currently adjusted X-ray reflectors 4 are displayed on the CCD camera 5, and then the operation in step 5 is repeated. Finally, the focused light spots generated by each layer of X-ray reflectors 4 can be individually adjusted to within the required accuracy range.

[0081] (2) No aperture is added to the previously installed X-ray reflector 4, so that parallel light passes through all the X-ray reflectors 4 and can generate a focused light spot on the CCD camera 5, and finally a light spot formed by the superposition of the focused light spots generated by each layer of X-ray reflectors 4 will be presented on the CCD camera 5. This method comprehensively considers the focused light spot effects generated by the X-ray reflectors 4 being installed and already installed, and then repeats the operation in step 5, and finally the superimposed focused light spots of the multi-layer reflectors can be adjusted to the required accuracy range.

[0082] The present invention has been described in detail above in conjunction with specific implementations and exemplary examples, but these descriptions cannot be understood as limiting the present invention. Those skilled in the art understand that, without departing from the spirit and scope of the present invention, a variety of equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its implementation methods, all of which fall within the scope of the present invention. The scope of protection of the present invention shall be subject to the attached claims.

[0083] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. An alignment evaluation system for multi-layer nested reflectors, characterized in that: It comprises a parallel light tube (1), a plane reflector (2), a bottom spoke plate (3), a CCD camera (5), a five-axis translation stage (6), a vertical rod (7) and a slider (8); The vertical rod (7) is arranged along the vertical direction; The CCD camera (5) is mounted on a five-axis displacement platform (6), which is mounted on a vertical rod (7) via a slider (8). The five-axis displacement platform (6) is used to fine-tune the position of the CCD camera (5), and the slider (8) is used to adjust the height of the CCD camera (5) when sliding along the vertical rod (7); The bottom radian plate (3) is arranged below the CCD camera (5), and a plurality of annular grooves are arranged on the bottom radian plate (3) for carrying the X-ray reflector (4); The horizontal parallel light emitted by the collimator (1) is reflected by the plane reflector (2) to form vertical parallel light, and the vertical parallel light passes through the bottom radian (3) or the bottom radian (3) and the X-ray reflector (4) to form an image on the CCD camera (5).

2. The alignment evaluation system for multi-layer nested reflectors according to claim 1, characterized in that: An alignment mark (13) is provided on the bottom spoke plate (3); The alignment mark (13) is a circular through hole, and the coaxiality between the circular through hole and the annular groove is better than 0.01 mm; After the vertical parallel light passes through the alignment mark (13) of the bottom radian (3), a circular bright spot is formed on the CCD camera (5), and the position of the bottom radian (3) when the center of the circular bright spot coincides with the center of the imaging field of the CCD camera (5) is used as the reference position.

3. The alignment evaluation system for multi-layer nested reflectors according to claim 1, characterized in that: It also includes an X-ray reflector position adjustment mechanism; The X-ray reflector position and posture adjustment mechanism is used to adjust the position and posture of each layer of X-ray reflectors (4) to complete the installation and adjustment of each layer of X-ray reflectors (4).

4. The alignment evaluation system for multi-layer nested reflectors according to claim 3, characterized in that: The X-ray reflector posture adjustment mechanism includes a number of ropes; One end of each rope is connected to a plurality of small holes evenly distributed in the circumferential direction of the upper end of the X-ray reflector (4), and the other end is connected to a driving motor. The driving motor adjusts the position of the X-ray reflector by driving each rope.

5. A method for evaluating the alignment of a multi-layer nested reflector, implemented by using the system for evaluating the alignment of a multi-layer nested reflector according to any one of claims 1 to 4, characterized in that: include: S1 converts the horizontal parallel light emitted by the collimator (1) into vertical parallel light after passing through the plane reflector (2); S2 installs a bottom radiator plate (3) on the optical path of parallel light in the vertical direction, and installs a CCD camera (5) above the bottom radiator plate (3); The bottom radial plate (3) is adjusted to a horizontal state, and the position of the CCD camera is adjusted so that the center of a circular bright spot formed on the CCD camera (5) after the parallel light passes through the bottom radial plate (3) coincides with the center of the imaging field of the CCD camera (5); S3 installs the i-th layer of X-ray reflectors (4) on the bottom radian (3); The height of the CCD camera (5) is adjusted by sliding the slider (8) up and down along the vertical rod (7) so that the CCD camera (5) is located within the estimated range of the focal plane height of the X-ray reflector (4); S4 finely adjusts the up and down position of the CCD camera (5) through a five-axis translation stage (6) so that the focusing surface of the first layer X-ray reflector (4) coincides with the imaging surface of the CCD camera (5); S5: adjusting the position of the first layer X-ray reflector (4) so ​​that the centroid of the focused light spot of the first layer X-ray reflector (4) coincides with the center of the imaging field of the CCD camera (5), and the half-energy diameter (HPD) of the focused light spot is within an estimated range; S6: bonding and fixing the first layer of X-ray reflectors (4) into the corresponding annular grooves on the bottom radiator plate (3), thereby completing the installation and adjustment of the first layer of X-ray reflectors (4); S7 installs the i-th layer of reflectors on the bottom radian plate (3), 2≤i≤n, and n is the total number of reflectors; S8 adjusts the position of the i-th layer X-ray reflector (4) so ​​that the centroid of the focused light spot of the i-th layer X-ray reflector (4) coincides with the center of the imaging field of the CCD camera (5), and the half-energy diameter (HPD) of the focused light spot is within the estimated range; S9: bonding and fixing the i-th layer X-ray reflector (4) into the corresponding annular groove on the bottom radiator plate (3), thereby completing the installation and adjustment of the i-th layer X-ray reflector (4); S10: Repeat steps S7 to S9 to adjust each layer of X-ray reflectors (4) until the adjustment of n layers of X-ray reflectors (4) is completed.

6. The method for evaluating the alignment of a multi-layer nested reflector according to claim 5, characterized in that: In step S2, a rectangular coordinate system is established with the center of the imaging field of the CCD camera (5) as the coordinate origin; Obtaining the deviation of the center of the circular bright spot from the coordinate origin in the X direction and the Y direction according to the coordinate of the center of the circular bright spot in the coordinate system; The five-axis translation stage (6) fine-adjusts the position of the CCD camera (5) according to the deviation between the center of the circular bright spot and the coordinate origin in the X direction and the Y direction, until the center of the circular bright spot coincides with the center of the imaging field of the CCD camera (5); The standard for the center of the circular bright spot to coincide with the center of the imaging field of the CCD camera (5) is that the distance between the center of the circular bright spot and the center of the imaging field of the CCD camera (5) is less than 1 pixel.

7. The method for evaluating the alignment of a multi-layer nested reflector according to claim 5, characterized in that: In step S3, when the CCD camera (5) is located within the estimated range of the height of the focal plane of the X-ray reflector (4), the estimated range is d±5 mm, where d is the focal length of the X-ray reflector (4).

8. The method for evaluating the alignment of multi-layer nested reflectors according to claim 5, characterized in that: In step S4, the standard for making the focusing plane of the first layer X-ray reflector (4) coincide with the imaging plane of the CCD camera (5) is that the height difference between the focusing plane of the first layer X-ray reflector (4) and the imaging plane of the CCD camera (5) is less than 0.1 mm.

9. The method for evaluating the alignment of a multi-layer nested reflector according to claim 6, characterized in that: In step S5 or step S8, the deviation of the centroid and the coordinate origin in the X direction and the Y direction are obtained according to the coordinates of the centroid of the focused light spot of the first or i-th X-ray reflector (4) in the coordinate system; The position of the first or i-th X-ray reflector (4) is adjusted according to the deviation of the center of mass and the origin of the coordinate in the X direction and the deviation in the Y direction, until the center of mass of the focused light spot of the X-ray reflector (4) coincides with the center of the imaging field of the CCD camera (5), and the half-energy diameter (HPD) of the focused light spot is within the estimated range; and the difference with the estimated value is less than 1″; The criterion for the centroid of the focused spot of the X-ray reflector (4) to coincide with the center of the imaging field of the CCD camera (5) is that the distance between the centroid of the focused spot of the X-ray reflector (4) and the center of the imaging field of the CCD camera (5) is less than 1 pixel; The standard for the half-energy diameter HPD of the focused light spot to be within the estimated range is that the difference between the half-energy diameter HPD of the focused light spot and the estimated value is less than 1″, and the estimated value is less than 10″.

10. The method for evaluating the alignment of multi-layer nested reflectors according to claim 5, characterized in that: When the second to nth layers of X-ray reflectors (4) are adjusted, an aperture is added to the X-ray reflectors (4) of the previous layer that have been adjusted; Alternatively, when adjusting the second to nth layers of X-ray reflectors (4), the distance between the centroid of the focused light spot obtained by superimposing the X-ray reflectors (4) of this layer and the previous layers and the center of the imaging field of the CCD camera (5) is less than 1 pixel, and the half-energy diameter (HPD) of the focused light spot is within an estimated range.

Images