Measurement system and method for calibrating the working efficiency of X-ray filters and reflectors

Abstract

The present invention relates to a measurement system and method for calibrating the working efficiency of X-ray filters and reflectors, comprising a vacuum unit, an aiming and collimating unit, a sample placement unit, an adjustment unit, an angle measurement unit, and a signal acquisition and control unit; the adjustment unit is used to adjust the working states of the aiming and collimating unit, the sample placement unit, and the angle measurement unit, and is connected to the signal acquisition and control unit; the vacuum unit is connected to a first vacuum chamber; the sample placement unit includes a filter sample holder and a reflector sample holder; the aiming and collimating unit is placed in the first vacuum chamber, and the sample placement unit, the adjustment unit, and the angle measurement unit are placed in a second vacuum chamber, and the two vacuum chambers are connected via a sealed vacuum flange. Compared with the prior art, the present invention can simultaneously measure multiple filter and reflector samples and measure input and output signals in real time, significantly improving measurement efficiency while reducing measurement errors.

Description

Technical Field

[0001] The present invention relates to the field of X-ray optical element working efficiency calibration, and in particular to a measurement system and method for calibrating the working efficiency of X-ray filters and reflectors. Background Art

[0002] Absolute measurement of soft X-ray energy spectra is a core component of ICF (inertial confinement fusion) research. Soft X-ray filters and mirrors are crucial conditioning and dispersion components in soft X-ray spectrum diagnostics. These components are key measurement components in key instruments commonly used in ICF energy spectrum and radiation flux diagnostics, such as the Dante spectrometer used in the National Institute of Fusion (NIF) laser facility in the United States and the SXS (Soft X-ray Spectrometer) and FXRD (Flat X-ray Diode) used in my country's Shenguang III laser facility. To ensure accurate measurement results, the efficiency of these optical components must be accurately calibrated.

[0003] Existing calibration devices for synchrotron X-ray components are primarily divided into transmission-type filter calibration devices and reflection-type reflectometer devices. Due to limitations in their optical structure, these existing calibration devices struggle to calibrate both transmission and reflection optical components. Furthermore, sample replacement processes require significant time, significantly reducing calibration efficiency. This presents significant challenges for X-ray optical component calibration, particularly under tight synchrotron radiation schedules. Furthermore, existing reflectometers, due to their single detector, are unable to simultaneously detect both input and output signals, leading to significant measurement errors when the intensity of the synchrotron radiation beam varies over time. Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a measurement system and method for calibrating the working efficiency of X-ray filters and reflectors.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A measurement system for calibrating the working efficiency of X-ray filters and reflectors, comprising a vacuum unit, an aiming and collimating unit, a sample placement unit, an adjustment unit, an angle measurement unit, and a signal acquisition and control unit; the adjustment unit is used to adjust the working states of the aiming and collimating unit, the sample placement unit, and the angle measurement unit, and the adjustment unit is connected to the signal acquisition and control unit; the vacuum unit is connected to a first vacuum chamber; the sample placement unit comprises a filter sample holder and a reflector sample holder; the aiming and collimating unit is placed in the first vacuum chamber, and the sample placement unit, the adjustment unit, and the angle measurement unit are placed in a second vacuum chamber, and the two vacuum chambers are connected by a sealed vacuum flange.

[0007] Furthermore, the vacuum unit is equipped with a vacuum pump and a high-precision vacuum gauge, and the vacuum degree of the device is ≤10 -3 pa.

[0008] Furthermore, the aiming and collimating unit includes a first slit and a second slit that can be adjusted vertically, and a first CCD camera and a second CCD camera that can be adjusted vertically for monitoring the slit light spot. The first slit is a horizontal slit, and the second slit is a vertical slit. The slit width adjustment range is 1 to 3 mm, the slit spacing is 200 mm, and the slit edges are coated with X-ray phosphor.

[0009] Furthermore, the angle measuring unit includes a scintillator and a vertically adjustable third CCD camera for monitoring the scintillator light spot. The scintillator is arranged on the inner wall of the second vacuum chamber. The third CCD camera is connected to the adjustment unit. The scintillator is a GAGG plastic scintillator. The scintillator is placed at the end of the optical path and has a diameter of 300 mm.

[0010] Furthermore, the signal acquisition and control unit includes two silicon photodiode detectors inside the second vacuum cavity, a weak current meter, a host computer, and a cable and a vacuum aviation plug flange for extracting signals arranged on the second vacuum cavity. The silicon photodiode is an AXUV-100 standard detector, and the sensitivity difference between the front and rear detectors is ≤2%, and the signal-to-noise ratio is ≥100.

[0011] Furthermore, the sensitivity of the weak current meter is in the pA level, and the data can be transmitted to the host computer in real time.

[0012] Furthermore, the host computer receives the real-time signal of the weak current meter, processes the electrical signals output by the front and rear silicon photodiode detectors, and calculates the transmittance of the filter sample and the reflectance of the reflector sample.

[0013] Furthermore, the adjustment unit includes a vacuum electrically controlled adjustment frame mounted in the slit, silicon photodiode, filter sample holder and reflector sample holder, and the vacuum electrically controlled adjustment frame performs 30 mm vertical adjustment on the slit, silicon photodiode and filter sample; the vacuum electrically controlled adjustment frame in the adjustment unit performs 30 mm vertical adjustment, 30 mm horizontal adjustment and 0 to 20 degrees angle adjustment on the multilayer mirror reflector sample; performs 15 mm vertical adjustment on the first and second CCD cameras for observing the slit; and performs 200 mm vertical adjustment on the third CCD camera for observing the scintillator spot.

[0014] Furthermore, the host computer in the signal acquisition control unit controls all the electric control adjustment racks and automatically switches the X-ray beam energy, filter samples and reflector samples through the Labview program.

[0015] Furthermore, the host computer receives the real-time signal of the weak current meter and calculates the average value and variance of the signal from the same sample in the same period.

[0016] A measurement method for calibrating a measurement system for the working efficiency of an X-ray filter and a reflector, comprising the following steps:

[0017] S1. Place multiple filter samples and reflector samples in the filter sample holder and reflector sample holder in the sample placement unit respectively, and adjust the vacuum degree in the device to ≤10 -3 Pa;

[0018] S2. Switch the synchrotron radiation X-ray beam to the 0th order diffraction light, aim and collimate the light path through the aiming and collimating unit, measure the grazing incidence angle of the reflector sample with the angle measuring unit, and adjust the adjustment unit to the required measurement angle of the reflector sample;

[0019] S3, switching the synchrotron radiation X-ray beam to 750 eV energy, placing the first silicon photodiode detector in the light path through the adjustment unit (4), measuring the data of the sample that has not passed through the reflector, and then placing the second silicon photodiode detector in the light path, measuring the data of the sample that has passed through the reflector;

[0020] S4. Scan the synchrotron radiation X-ray beam within the energy range of 100-1500 eV. First, vertically adjust the two silicon photodiode detectors out of the light path through the adjustment unit (4), replace the filter sample and the reflector sample, then place the first silicon photodiode detector in the light path through the adjustment unit (4), measure the data of the sample that has not passed through the reflector, then place the second silicon photodiode detector in the light path, measure the data of the sample that has passed through the reflector, and the signal acquisition control unit (6) processes the electrical signals output by the front and rear silicon photodiode detectors and calculates the transmittance of the filter sample and the reflectance of the reflector sample.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The optical structure design of the present invention takes into account the calibration of the working efficiency of both X-ray transmission and reflection optical elements. By arranging a filter sample holder and a reflector sample holder in the second vacuum chamber, X-ray filters and reflectors can be calibrated simultaneously. The sample holder can accommodate multiple samples, saving a lot of time in sample replacement and significantly improving the measurement efficiency of calibrating X-ray optical elements.

[0023] 2. The present invention uses two silicon photodiodes with a sensitivity difference of ≤2% as signal detectors, which can measure the input signal and the output signal after transmission or reflection through the optical element in real time, avoiding the large amount of error caused by the change of synchrotron radiation beam intensity over time, and significantly improving the measurement accuracy of calibrated X-ray optical elements.

[0024] 3. The present invention uses a third CCD camera to monitor the X-ray spot on the X-ray scintillator at the end of the optical path to measure the grazing incidence angle of the reflector in real time. Traditional reflectometers directly use the rotation angle as the grazing incidence angle. The angle measurement method adopted by the present invention effectively avoids the angle measurement errors caused by sample installation and equipment aging in traditional reflectometers, significantly improving the measurement accuracy of calibrated X-ray reflectors.

[0025] 4. The present invention is provided with an adjustment unit for adjusting the working states of the aiming and collimating unit, the sample placement unit, and the angle measurement unit. The vacuum electric-controlled adjustment frame in the adjustment unit vertically adjusts the slit, silicon photodiode, and filter sample; vertically, horizontally, and angularly adjusts the multilayer mirror reflector sample; vertically adjusts the first and second CCD cameras for observing the slit; and precisely vertically adjusts the third CCD camera for observing the scintillator spot. This satisfies different measurement requirements and is practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the present invention;

[0027] Figure 2 Schematic diagram of the filter sample holder of the present invention;

[0028] Figure 3 Schematic diagram of the reflector sample holder of the present invention;

[0029] Figure 4 Schematic diagram of the method for measuring the grazing incidence angle of a reflector according to the present invention.

[0030] Numbers in the figure: vacuum unit 1, aiming and collimation unit 2, sample placement unit 3, adjustment unit 4, angle measurement unit 5, signal acquisition and control unit 6, reflector sample holder outer frame 31, reflector sample holder turntable 32, reflector frame 33, reflector sample 34, filter holder sample holder outer frame 35, filter holder sample holder fixing plate 36, filter sample 37, GAGG plastic scintillator 51. DETAILED DESCRIPTION

[0031] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0032] A measurement system for calibrating the working efficiency of X-ray filters and reflectors, comprising a vacuum unit 1, an aiming and collimating unit 2, a sample placement unit 3, an adjustment unit 4, an angle measuring unit 5 and a signal acquisition and control unit 6; the adjustment unit 4 is used to adjust the working states of the aiming and collimating unit 2, the sample placement unit 3 and the angle measuring unit 5, and the adjustment unit 4 is connected to the signal acquisition and control unit 6; the vacuum unit 1 is connected to a first vacuum chamber; the sample placement unit 3 includes a filter sample holder and a reflector sample holder; the aiming and collimating unit 2 is placed in the first vacuum chamber, and the sample placement unit 3, the adjustment unit 4 and the angle measuring unit 5 are placed in a second vacuum chamber, and the two vacuum chambers are connected by a sealed vacuum flange.

[0033] Vacuum unit 1 is equipped with a vacuum pump and a high-precision vacuum gauge, and the vacuum degree of the device is ≤10 -3 pa; The aiming and collimating unit 2 includes a first slit and a second slit that can be adjusted vertically, and a first CCD camera and a second CCD camera that can be adjusted vertically for monitoring the slit light spot. The first slit is a horizontal slit, and the second slit is a vertical slit. The slit width adjustment range is 1 to 3 mm, the slit spacing is 200 mm, and the slit edge is coated with X-ray phosphor.

[0034] The angle measuring unit 5 includes a scintillator and a vertically adjustable third CCD camera for monitoring the scintillator light spot. The scintillator is arranged on the inner wall of the second vacuum chamber. The third CCD camera is connected to the adjustment unit 4. The scintillator is a GAGG plastic scintillator. The scintillator is placed at the end of the optical path and has a diameter of 300 mm.

[0035] The signal acquisition control unit 6 includes two silicon photodiode detectors inside the second vacuum cavity, a weak current meter, a host computer, and a cable and a vacuum aviation plug flange for extracting signals arranged on the second vacuum cavity. The silicon photodiode is an AXUV-100 standard detector, and the sensitivity difference between the front and rear detectors is ≤2%, and the signal-to-noise ratio is ≥100; the weak current meter has a sensitivity of the pA level and can transmit data to the host computer in real time.

[0036] The host computer receives the real-time signal from the weak current meter and processes the electrical signals output by the front and rear silicon photodiode detectors to calculate the transmittance of the filter sample and the reflectance of the reflector sample.

[0037] The adjustment unit 4 includes a vacuum electrically controlled adjustment frame mounted in the slit, silicon photodiode, filter sample holder and reflector sample holder, and the vacuum electrically controlled adjustment frame performs 30 mm vertical adjustment on the slit, silicon photodiode and filter sample; the vacuum electrically controlled adjustment frame in the adjustment unit performs 30 mm vertical adjustment, 30 mm horizontal adjustment and 0 to 20 degrees angle adjustment on the multilayer mirror reflector sample; performs 15 mm vertical adjustment on the first and second CCD cameras for observing the slit; and performs 200 mm vertical adjustment on the third CCD camera for observing the scintillator spot.

[0038] The host computer in the signal acquisition control unit 6 controls all the electronically controlled adjustment racks and automatically switches the X-ray beam energy and samples through the Labview program.

[0039] A measurement method for calibrating a measurement system for the working efficiency of an X-ray filter and a reflector, comprising the following steps:

[0040] S1, place multiple filter samples and reflector samples in the filter sample rack and reflector sample rack in the sample placement unit 3 respectively, and adjust the vacuum degree in the device to ≤10 by the vacuum unit 1. -3 Pa;

[0041] S2. Switch the synchrotron radiation X-ray beam to the 0th order diffraction light, aim and collimate the light path through the aiming and collimating unit 2, measure the grazing incidence angle of the reflector sample by the angle measuring unit 5, and adjust the adjustment unit 4 to the required measurement angle of the reflector sample;

[0042] S3, switching the synchrotron radiation X-ray beam to 750 eV energy, and placing the silicon photodiode detector in the light path through the adjustment unit 4;

[0043] S4. Scan the synchrotron radiation X-ray beam in the energy range of 100-1500 eV, switch the silicon photodiode detector and the sample through the adjustment unit 4, process the electrical signals output by the front and rear silicon photodiode detectors through the signal acquisition control unit 6, and calculate the transmittance of the filter sample and the reflectance of the mirror sample.

[0044] This embodiment further illustrates the content of the present invention by taking the measurement device and method for calibrating an X-ray filter and a compact X-ray multilayer film array reflector for ICF soft X-ray energy spectrum measurement as examples.

[0045] like Figure 1-3The figure shows a schematic structural diagram of a measurement system for calibrating the working efficiency of X-ray filters and reflectors, including a vacuum unit 1, an aiming and collimating unit 2, a sample placement unit 3, an adjustment unit 4, an angle measurement unit 5, a signal acquisition and control unit 6, a reflector sample holder outer frame 31, a reflector sample holder turntable 32, a reflector frame 33, a reflector sample 34, a filter holder sample holder outer frame 35, a filter holder sample holder fixing plate 36, a filter sample 37, and a GAGG plastic scintillator 51.

[0046] Multiple X-ray filter samples 37 are placed in a filter rack slot customized with the filter rack sample rack outer frame 35. The surface of the filter sample frame is flush with the surface of the filter rack slot. The filter rack sample rack fixing plate 36 is used to fix the filter sample 37. The adjustment unit 4 can vertically adjust the filter sample 37 by 30 mm.

[0047] The compact X-ray multilayer film array reflector sample 34 is fixed from the side by the reflector frame 33. The surface of the reflector frame 33 is in the same plane as the selection center of the reflector sample holder turntable 32, ensuring the measurement accuracy of the grazing incidence angle. The adjustment unit 4 can adjust the reflector sample 34 vertically within a range of 30 mm, horizontally by 30 mm, and at an angle of 0 to 20 degrees.

[0048] Based on the above device, the measurement method for calibrating an X-ray filter and a compact X-ray multilayer film array reflector for ICF soft X-ray spectrum measurement in this embodiment includes the following steps:

[0049] Step 1: Place the X-ray filter and the multilayer film array reflector sample in the sample holder, and adjust the vacuum degree in the device to ≤10 by the front stage mechanical pump and the rear stage molecular pump in the vacuum unit 1. -3 pa, observe whether the vacuum degree meets the requirements through the vacuum gauge. If it meets the requirements, proceed to step 2.

[0050] Step 2: Switch the synchrotron radiation beamline to the zero-order diffraction light. Use two slits coated with X-ray phosphor at a distance of 150 mm in the aiming collimator unit 2. By monitoring the first and second CCD cameras, confirm that the beam path passes through the two slits; Figure 4 As shown, the angle measuring unit 5 monitors the third CCD camera and cooperates with the GAGG plastic scintillator 51 to measure the position of the direct light spot of the beam, the parallel position of the beam and the reflector sample 34, and the position of the light spot reflected by the beam passing through the reflector sample 34. The accurate grazing incidence angle of the reflector sample 34 is calculated based on the positional relationship between the three light spots.

[0051] Step 3: Switch the synchrotron radiation X-ray beam to 750 eV energy, adjust the positions of the front and rear silicon photodiode detectors respectively through the adjustment unit 4, monitor the signal changes in the signal acquisition control unit 6, and when the signal is basically stable, the detector is located in the beam line light path, and the detector position at this time is recorded.

[0052] Step 4: For any sample, scan the synchrotron radiation X-ray beam in the energy range of 100-1500 eV, automatically switch the detector through the adjustment unit 4, process the signals of the front and rear detectors through the signal acquisition control unit 6, and calculate the transmittance of the filter sample 37 and the reflectance of the mirror sample 34 and other related parameters.

[0053] Step 5: Reset the synchrotron X-ray beam and automatically switch samples via the adjustment unit 4. Repeat steps 1 and 4 for the reflector sample 34. Repeat step 4 for the filter sample 37.

[0054] The above describes in detail the preferred embodiments of the present invention. It should be understood that those skilled in the art can make numerous modifications and variations based on the concepts of the present invention without inventive effort. Therefore, any technical solutions that can be derived by those skilled in the art through logical analysis, reasoning, or limited experimentation based on the concepts of the present invention and the prior art should be within the scope of protection defined by the claims.

Claims

1. A measurement system for calibrating the working efficiency of X-ray filters and reflectors, characterized in that: It comprises a vacuum unit (1), an aiming and collimating unit (2), a sample placement unit (3), an adjustment unit (4), an angle measurement unit (5) and a signal acquisition and control unit (6); The adjustment unit (4) is used to adjust the working states of the aiming and collimating unit (2), the sample placement unit (3) and the angle measuring unit (5), and the adjustment unit (4) is connected to the signal acquisition control unit (6); The vacuum unit (1) is connected to the first vacuum chamber; The sample placement unit (3) comprises a filter sample holder and a reflector sample holder; The aiming and collimating unit (2) is placed in a first vacuum chamber, the sample placement unit (3), the adjustment unit (4) and the angle measurement unit (5) are placed in a second vacuum chamber, and the two vacuum chambers are connected via a sealed vacuum flange; The vacuum unit (1) is equipped with a vacuum pump and a high-precision vacuum gauge, and the vacuum degree of the device is ≤10 -3 pa; The aiming and collimating unit (2) comprises a first slit and a second slit that can be adjusted vertically, and a first CCD camera and a second CCD camera that can be adjusted vertically for monitoring the slit light spot. The first slit is a horizontal slit, and the second slit is a vertical slit. The slit width adjustment range is 1 to 3 mm, the slit spacing is 200 mm, and the slit edges are coated with X-ray phosphor. The angle measuring unit (5) includes a scintillator and a third CCD camera that can be adjusted vertically for monitoring the scintillator light spot. The scintillator is arranged on the inner wall of the second vacuum chamber. The third CCD camera is connected to the adjustment unit (4). The scintillator is a GAGG plastic scintillator. The scintillator is placed at the end of the optical path and has a diameter of 300 mm. The signal acquisition control unit (6) includes two silicon photodiode detectors inside the second vacuum chamber, a weak current meter, a host computer, and a cable and a vacuum aviation plug flange for extracting signals arranged on the second vacuum chamber. The silicon photodiode is an AXUV-100 standard detector, the difference in sensitivity between the front and rear detectors is ≤2%, and the signal-to-noise ratio is ≥100. The adjustment unit (4) includes a vacuum electric control adjustment frame mounted on the slit, silicon photodiode, filter sample holder and reflector sample holder, wherein the vacuum electric control adjustment frame performs 30 mm vertical adjustment on the slit, silicon photodiode and filter sample; the vacuum electric control adjustment frame in the adjustment unit performs 30 mm vertical adjustment, 30 mm horizontal adjustment and 0 to 20 degrees angle adjustment on the multilayer mirror reflector sample; performs 15 mm vertical adjustment on the first CCD camera and the second CCD camera for observing the slit; and performs 200 mm vertical adjustment on the third CCD camera for observing the scintillator spot.

2. A measurement system for calibrating the working efficiency of X-ray filters and reflectors according to claim 1, characterized in that: The sensitivity of the weak current meter is in the pA range and the data can be transmitted to the host computer in real time.

3. A measurement system for calibrating the working efficiency of X-ray filters and reflectors according to claim 2, characterized in that: The host computer receives the real-time signal of the weak current meter, processes the electrical signals output by the front and rear silicon photodiode detectors, and calculates the transmittance of the filter sample and the reflectance of the reflector sample.

4. A measurement system for calibrating the working efficiency of X-ray filters and reflectors according to claim 1, characterized in that: The host computer in the signal acquisition control unit (6) controls all the electric control adjustment racks and automatically switches the X-ray beam energy, filter samples and reflector samples through the Labview program.

5. A measurement method for calibrating a measurement system for the working efficiency of an X-ray filter and a reflector according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Place multiple filter samples and reflector samples on the filter sample rack and reflector sample rack in the sample placement unit (3), respectively, and adjust the vacuum degree in the device to ≤10 by the vacuum unit (1). -3 Pa; S2, switching the synchrotron radiation X-ray beam to the 0th order diffraction light, aiming and collimating the light path through the aiming and collimating unit (2), measuring the grazing incidence angle of the reflector sample by the angle measuring unit (5), and adjusting the adjustment unit (4) to the required measurement angle of the reflector sample; S3, switching the synchrotron radiation X-ray beam to 750 eV energy, placing the first silicon photodiode detector in the light path through the adjustment unit (4), measuring the data of the sample that has not passed through the reflector, and then placing the second silicon photodiode detector in the light path, measuring the data of the sample that has passed through the reflector; S4. Scan the synchrotron radiation X-ray beam within the energy range of 100-1500 eV. First, vertically adjust the two silicon photodiode detectors out of the light path through the adjustment unit (4), replace the filter sample and the reflector sample, then place the first silicon photodiode detector in the light path through the adjustment unit (4), measure the data of the sample that has not passed through the reflector, then place the second silicon photodiode detector in the light path, measure the data of the sample that has passed through the reflector, and the signal acquisition control unit (6) processes the electrical signals output by the front and rear silicon photodiode detectors and calculates the transmittance of the filter sample and the reflectance of the reflector sample.

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