Plasma visible light radiation power measurement system and method

Abstract

The invention relates to a plasma visible radiation power measurement system and method, belongs to the technical field of visible radiation performance measurement, and solves the technical problems of insufficient linear dynamic range, low sensitivity and incapability of quantitative measurement in visible radiation power measurement. The measuring system comprises a vacuum pipeline, a diaphragm, a quartz vacuum sealing window, a reflecting mirror, an electromagnetic shielding box, a signal synchronizing and recording module, a photoelectric detector, a beam splitting type optical fiber bundle, an optical filter, an optical attenuation piece and a storage module. The measuring method comprises the steps that the plasma radiation source to be measured emits visible light and a trigger electric signal, the visible light is transmitted to the photoelectric detector through the diaphragm, the quartz vacuum sealing window, the reflector, the beam splitting type optical fiber bundle, the optical filter and the optical attenuation piece, the trigger electric signal triggers the data acquisition unit to receive an electric signal of the photoelectric detector, and the electric signal is stored in the storage module.

Description

Technical Field

[0001] This invention belongs to the field of visible light radiation performance measurement technology, specifically relating to a plasma visible light radiation power measurement system and method. Background Technology

[0002] In inertial confinement fusion research, visible light radiation characteristics reflect rich physical information about the implosion dynamics. In particular, the visible light radiation power waveform is one of the most important experimental diagnostic parameters. Among existing visible light radiation power measurement techniques, measurement systems composed of fast silicon photodiodes, multimode optical fibers, and quartz filters have been applied. However, due to the influence of the system's optical path structure and the linear current of the photodetector, their quantitative measurement level and linear dynamic range are very limited when measuring visible light power over hundreds of nanoseconds.

[0003] Zhang Zhengwei's paper "Visible Light Radiation Characteristics of Zig-Pinched Wire Arrays," published in *High Power Laser and Particle Beams*, 2013, 25(5), 1307-1310, discloses a visible light radiation power measurement system, such as... Figure 1 As shown, the system consists of a quartz filter 01, a multimode fiber optic cable 02, a silicon phototube 03, and an oscilloscope 04. The measurement system uses the silicon phototube 03 to detect signals. A quartz filter 01 that allows visible light to pass through is added in front of the silicon phototube 03 to filter out the influence of radiation from other wavelengths. The multimode fiber optic cable 02 is used to collect and transmit signals. The silicon phototube 03 is combined with a broadband oscilloscope 04 to complete the photoelectric conversion signal recording. However, the measurement system has low sensitivity, limited linear dynamic range, and does not limit plasma radiation in a specific area, making it unable to meet the quantitative measurement of weak visible light radiation power over long distances.

[0004] In summary, existing measurement systems suffer from insufficient linear dynamic range, low sensitivity, and inability to quantitatively measure plasma radiation pulses with a width of 100 nanoseconds over long distances. Summary of the Invention

[0005] To overcome the shortcomings of insufficient linear dynamic range, low sensitivity, and inability to quantitatively measure visible light radiation power, this invention proposes a plasma visible light radiation power measurement system and method.

[0006] The technical solution adopted by this invention to solve its technical problem is:

[0007] A plasma visible light radiation power measurement system includes a vacuum tube, an aperture, a quartz vacuum sealed window, a reflector, an electromagnetic shielding box, a signal synchronization and recording module, a photodetector, a bundled fiber optic cable, a filter, an optical attenuator, and a storage module.

[0008] The signal synchronization and recording module includes a high-voltage power supply unit, a data acquisition unit, a 220V uninterruptible power supply, a synchronous photoelectric converter, and a synchronous electro-optical converter.

[0009] The plasma radiation source to be tested is located inside the front end of the vacuum pipe; the quartz vacuum-sealed window is located at the rear end of the vacuum pipe and is coaxial with the vacuum pipe; the aperture, used to select the irradiation area of ​​the plasma radiation source to be tested, is located inside the vacuum pipe. The reflector is located outside the vacuum pipe and is at a 45° angle to the incident visible light beam emitted by the plasma radiation source to be tested. The incident end of the split-beam fiber bundle is located on the outgoing light path of the reflector, and the outgoing light from the outgoing end of the split-beam fiber bundle passes through a filter and an optical attenuator before entering the photodetector. Several photodetectors are arranged in parallel. The photodetectors, filters, optical attenuators, high-voltage power supply unit, data acquisition unit, 220V uninterruptible power supply, and synchronous photoelectric converter are located inside an electromagnetic shielding box.

[0010] The photodetector is connected to the data acquisition unit via a signal cable. The plasma radiation source under test is connected to the synchronous electro-optical converter via a signal cable. The synchronous electro-optical converter is connected to the synchronous photodetector via a single-mode dual-core optical fiber. The synchronous photodetector is then connected to the data acquisition unit via a signal cable. The storage module is connected to the data acquisition unit via a single-mode dual-core optical fiber. The data acquisition unit is used to acquire the visible light radiation power of the plasma detected by the photodetector. The high-voltage power supply unit is connected to the power supply terminal of the photodetector via a high-voltage power supply cable to provide high voltage to the photodetector. The 220V uninterruptible power supply is connected to the high-voltage power supply unit, the data acquisition unit, and the synchronous photodetector.

[0011] The aforementioned plasma visible light radiation power measurement system has a three-stage aperture, comprising a near-end aperture, an intermediate aperture, and a far-end aperture arranged sequentially along the visible light emission direction of the plasma.

[0012] The near-end and far-end apertures are used to select the irradiation area of ​​the plasma radiation source to be measured; the intermediate aperture is used to block visible light outside the selected irradiation area from illuminating the reflector. The inner diameters of the near-end and far-end apertures determine the size of the targeted plasma irradiation area.

[0013] In the aforementioned plasma visible light radiation power measurement system, the aperture is made of tungsten, and its thickness and aperture are both on the order of millimeters.

[0014] In the aforementioned plasma visible light radiation power measurement system, the substrate of the reflector is K9 glass, and the front surface of the substrate is coated with Al material, with the thickness of Al on the order of micrometers.

[0015] In the aforementioned plasma visible light radiation power measurement system, the split-beam fiber bundle is used to transmit the visible light reflected by the reflector to the photodetector.

[0016] The photodetector consists of four photodetectors arranged in parallel, and the number of bundles in the split-type fiber bundle is four.

[0017] The incident end face of the split-type fiber bundle is located on the outgoing light path of the reflector and is perpendicular to the direction of the outgoing visible light of the reflector.

[0018] The diameter of the incident end of the split-type fiber bundle is determined by the size of the source region of the plasma radiation source to be measured and the aperture of the aperture.

[0019] The incident end of the split-type fiber optic bundle includes a central circular area fiber, a spacer layer, and an outer ring area fiber.

[0020] The output end of the split-type fiber optic bundle includes the first output end, the second output end, the third output end, and the fourth output end.

[0021] The fiber cores in the central circular region have the same diameter and are evenly distributed to the first and second output ends, with the same splitting ratio at the first and second output ends. The fiber cores in the outer annular region have the same diameter and are evenly distributed to the third and fourth output ends, with the same splitting ratio at the third and fourth output ends. The spacer layer is made of aluminum alloy.

[0022] In the aforementioned plasma visible light radiation power measurement system, the diameter of the central circular region at the incident end of the split-beam fiber bundle is 14 mm, the outer diameter of the aluminum alloy spacer layer is 19 mm, and the outer diameter of the outer annular region is 33.4 mm.

[0023] The diameters of the first and second output terminals are both 10.4 mm, and the diameters of the third and fourth output terminals are both 21.3 mm.

[0024] In the aforementioned plasma visible light radiation power measurement system, the gain of the photodetector is 1 to 1E5, and the response time is less than 3 ns.

[0025] The aforementioned plasma visible light radiation power measurement system includes an electromagnetic shielding box comprising, from the inside out, an inner shielding box, an insulating medium, and an outer shielding box, arranged sequentially from the inside out.

[0026] The outer shielding enclosure is used for grounding.

[0027] The electromagnetic shielding box is provided with holes for the output end of the split-type optical fiber bundle and for single-mode dual-core optical fiber to pass through.

[0028] A method for measuring visible light radiation power in plasma, using the aforementioned plasma visible light radiation power measurement system, includes:

[0029] When measuring the visible light radiation power of the plasma radiation source under test, the plasma radiation source under test emits visible light and trigger electrical signals.

[0030] Visible light emitted from the plasma radiation source under test is sequentially irradiated onto a reflector through an aperture and a quartz vacuum-sealed window. The reflected light from the reflector is then sequentially transmitted to a photodetector through a split-beam fiber bundle, a filter, and an optical attenuator. The photodetector converts the visible light signal into an electrical signal.

[0031] The trigger electrical signal emitted by the plasma radiation source under test is transmitted to the synchronous electro-optical converter via a signal cable. The synchronous electro-optical converter converts the trigger electrical signal into an optical signal. The optical signal converted by the synchronous electro-optical converter is transmitted to the synchronous photoelectric converter via a single-mode dual-core optical fiber. The synchronous photoelectric converter converts the received optical signal into an electrical signal. The electrical signal converted by the synchronous photoelectric converter is transmitted to the data acquisition unit. The trigger data acquisition unit receives the electrical signal from the photodetector, converts the electrical signal from the photodetector into a digital signal and records it. The recorded digital signal is transmitted to the storage module for storage via a single-mode dual-core optical fiber.

[0032] The beneficial effects of this invention are:

[0033] A plasma visible light radiation power measurement system is disclosed. Visible light radiated by the plasma radiation source under test is irradiated onto a reflector after passing through a three-stage aperture. The visible light signal reflected by the reflector is collected by a photodetector in an electromagnetic shielding box after passing through a bundle of split optical fibers and converted into an electrical signal. The electrical signal is transmitted to a storage module by a data acquisition unit for recording. This system solves the technical problems of low sensitivity, limited dynamic range, and low quantification level in existing measurement systems when measuring plasma radiation visible light pulses with a pulse width of 100 nanoseconds over long distances.

[0034] A plasma visible light radiation power measurement system employs a split-beam fiber optic bundle to transmit visible light to a photodetector. The photodetector and signal synchronization and recording module are housed within an electromagnetically shielded box, with the synchronous electro-optic converter of the signal synchronization and recording module located outside the shielded box. This design addresses the electromagnetic sensitivity of the high-sensitivity photodetector to the testing environment, improving the sensitivity of visible light power detection. Furthermore, the split-beam fiber optic bundle, matched with photodetectors of varying sensitivities, achieves a wider linear dynamic range for the detection system.

[0035] A plasma visible light radiation power measurement system is disclosed. After passing through three apertures, only a portion of the plasma radiation's visible light can illuminate the reflecting mirror. The observed irradiation area is determined by the apertures of the near-end and far-end apertures. Compared to existing optical path designs, the three-stage aperture system improves the correspondence between measurement data and the radiation source's radiation distribution, facilitating the physical analysis of the measurement data.

[0036] A plasma visible light radiation power measurement system employs fiber optic bundles for regional collection and bundled transmission to collect and transmit visible light signals to a photodetector. By adjusting the dimensions of each region at the incident end—namely, the diameter of the central circular region and the inner and outer diameters of the outer annular region—the visible light radiation power of different sub-regions within the observable radiation area of ​​the plasma source region can be conveniently measured.

[0037] A plasma visible light radiation power measurement system utilizes a reflector to reflect visible light perpendicular to the incident direction of visible light radiation from the plasma, causing the incident end face of the split fiber bundle to deviate from the radiation direction of the plasma radiation source. This solves the problem that high-energy ray particles directly excite the fiber bundle to emit light, thus affecting the accuracy of visible light radiation power measurement. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of an existing visible light radiation power measurement system;

[0039] Figure 2 This is a schematic diagram of the plasma visible light radiation power measurement system according to Embodiment 1 of the present invention;

[0040] Figure 3 This is a schematic diagram of the incident end face structure of a split-type optical fiber bundle according to Embodiment 1 of the present invention;

[0041] Figure 4 This is a schematic diagram of the end face structure of the output end of the split-type optical fiber bundle according to Embodiment 1 of the present invention.

[0042] Figure label:

[0043] 01-Quartz filter, 02-Multimode optical fiber, 03-Silicon phototube, 04-Oscilloscope;

[0044] 1-Plasma radiation source to be tested, 2-Vacuum pipe, 3-Aperture, 4-Vacuum-sealed quartz window, 5-Reflector, 6-Electromagnetic shielding box, 7-Signal synchronization and recording module, 8-Photodetector, 9-Near-end aperture, 10-Middle aperture, 11-Far-end aperture, 12-Bundled fiber optic bundle, 13-Filter, 14-Optical attenuator, 15-High-voltage power supply unit, 16-Data acquisition unit, 17-220V uninterruptible power supply, 18-Synchronous photoelectric converter, 19-Synchronous electro-optic converter, 20-Storage module, 21-Signal cable, 22-High-voltage power supply cable, 23-Single-mode dual-core fiber, 24-Fiber optic cable in the central circular area, 25-Spacer layer, 26-Fiber optic cable in the outer ring area. Detailed Implementation

[0045] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0046] Example 1

[0047] like Figure 2 As shown, a plasma visible light radiation power measurement system includes a vacuum pipe 2, a quartz vacuum-sealed window 4, a reflector 5, a beam splitter fiber bundle 12, and photodetectors 8. The front end of the vacuum pipe 2 is used to set the plasma radiation source 1 to be measured. The rear end of the vacuum pipe 2 is equipped with the quartz vacuum-sealed window 4. The reflector 5 is set outside the vacuum pipe 2 and is at a 45° angle to the incident visible light beam emitted by the plasma radiation source 1. The system also includes a three-stage aperture 3, an electromagnetic shielding box 6, a signal synchronization and recording module 7, and a storage module 20, all coaxially arranged inside the vacuum pipe 2 and located before the quartz vacuum-sealed window 4. The three-stage aperture 3 is used to select the irradiation area of ​​the plasma radiation source 1 to be measured. The incident end of the beam splitter fiber bundle 12 is located on the outgoing light path of the reflector 5 and is connected to the incident ends of multiple photodetectors 8.

[0048] The signal synchronization and recording module 7 includes a high-voltage power supply unit 15, a data acquisition unit 16, a 220V uninterruptible power supply 17, a synchronous photoelectric converter 18, and a synchronous electro-optical converter 19 located outside the electromagnetic shielding box 6, all housed inside the electromagnetic shielding box 6. The high-voltage power supply unit 15 is connected to the power supply terminals of multiple photoelectric detectors 8 via a high-voltage power supply cable 22 to provide high voltage to the photoelectric detectors 8. The data acquisition unit 16 is connected to the output terminals of multiple photoelectric detectors 8 and the storage module 20 via signal cables 21 to record the data measured by the photoelectric detectors 8 and transmit the data to the storage module 20. The sampling rate of the data acquisition unit 16 is determined based on the time characteristics of the plasma radiation source 1 under test.

[0049] The 220V uninterruptible power supply 17 is connected to the high-voltage power supply unit 15, the data acquisition unit 16, and the synchronous photoelectric converter 18, respectively. The synchronous photoelectric converter 18 is connected to the synchronous electro-optic converter 19 through the single-mode dual-core optical fiber 23 and to the data acquisition unit 16 through the signal cable 21. The synchronous electro-optic converter 19 is connected to the plasma radiation source 1 under test through the signal cable 21 and is used to receive the trigger electrical signal.

[0050] Vacuum pipe 2 is a cylindrical stainless steel tube with a vacuum-sealed window at its end. The plasma radiation source 1 to be measured is located inside the front end of vacuum pipe 2. A three-stage aperture 3 is coaxially positioned inside the middle section of vacuum pipe 2, in front of the quartz vacuum-sealed window 4. The three-stage aperture 3 includes a near-end aperture 9, a middle aperture 10, and a far-end aperture 11 arranged sequentially along the visible light emission direction. The near-end aperture 9 and the far-end aperture 11 are used to select the irradiation area of ​​the plasma radiation source 1 to be measured. The middle aperture 10 is used to block visible light outside the selected irradiation area from illuminating the reflector 5. The inner diameters of the near-end aperture 9 and the far-end aperture 11 determine the size of the targeted plasma irradiation area. The three-stage aperture 3 is made of tungsten and has a thickness on the order of mm. The distance between the three-stage aperture 3 and the plasma radiation source 1 to be measured, as well as the aperture of the three-stage aperture 3, are selected according to the intensity of the plasma radiation source 1 to be measured and the size of the measurement irradiation area. Generally, the aperture of the three-stage aperture 3 is on the order of mm.

[0051] The reflector 5 has an Al material coated on the front surface of the K9 glass substrate. The thickness of the Al material is on the order of micrometers. It reflects the incident visible light to the incident end face of the beam while ensuring a high reflectivity for visible light.

[0052] The split-type fiber bundle 12 is used to transmit the visible light reflected by the reflector 5 in regions and proportions to the output end of the split-type fiber bundle 12; the output end of the split-type fiber bundle 12 is connected to the input end of multiple photodetectors 8 respectively.

[0053] like Figure 2 As shown, the incident end face of the split-type fiber bundle 12 is located on the outgoing light path of the reflector and is perpendicular to the incident visible light direction. The incident end diameter and the size of each region of the split-type fiber bundle 12 are determined according to the source region size of the plasma radiation source 1 to be measured and the aperture of the third-order aperture. In this embodiment, the outgoing end diameter of the split-type fiber bundle 12 is determined according to the incident end diameter, the area of ​​each region of the incident end, the number of splits, and the size of the photosensitive surface of the photodetector 8. The outgoing light of the split-type fiber bundle 12 should fill the photosensitive surface of the photodetector 8 as much as possible, while being illuminated by the light from the photodetector 8. The sensitive surface is completely collected. In this embodiment, there are four photodetectors 8, and the number of bundles of the split-type fiber bundle 12 is 4. The diameter of the central circular region of the incident end of the split-type fiber bundle 12 is 14mm, the outer diameter of the aluminum alloy spacer layer is 19mm, and the outer diameter of the outer annular region is 33.4mm. The fiber in the central circular region is evenly distributed to the first output end and the second output end. The diameter of the first output end and the second output end is 10.4mm. The fiber in the outer annular region is evenly distributed to the third output end and the fourth output end. The diameter of the third output end and the fourth output end is 21.3mm.

[0054] like Figure 3 , Figure 4As shown, the incident end of the bundled fiber optic bundle 12 is a whole composed of a central circular region fiber 24, an aluminum alloy spacer layer 25, and an outer annular region fiber 26. The output end of the bundled fiber optic bundle 12 is divided into four bundles. Two of these bundles originate from the central circular region fiber, and they have the same diameter and the same number of fiber cores. Each fiber core in each bundle is evenly distributed within the central circular region of the incident end face, achieving the same splitting ratio at different output ends. The other two bundles originate from the outer annular region fiber, and they have the same diameter and the same number of fiber cores. Each fiber core in each bundle is evenly distributed within the outer annular region of the incident end face, achieving the same splitting ratio at different output ends. The incident end of the bundled fiber optic bundle 12 is divided into a central circular region fiber 24, an aluminum alloy spacer layer 25, and an outer annular region fiber 26. The central circular region and the outer annular region are composed of densely packed fibers, with a total length of approximately 2 to 3 meters. The fiber bundle is split at a distance of 0.5m to 1.5m from the incident end. The outer diameter of the annular region on the outer side of the incident end of the split fiber bundle 12 should be less than 50mm to completely collect the visible light reflected by the reflector, while not being too large to avoid affecting its flexibility. The incident end of the split fiber bundle 12 consists of a central circular region and an outer annular region for all fibers. The fibers near the middle and rear ends of the split fiber bundle 12 are evenly split into two bundles to ensure that the output light from the same region has minimal difference.

[0055] The gain of the photodetector 8 is 1 to 1E5 and the response time is less than 3 ns. The photodetector 8 is a photomultiplier tube. In other embodiments, a phototube can also be used. Its gain is determined according to the intensity of the plasma radiation source 1 to be measured, and is usually in the range of 1 to 1E5.

[0056] Furthermore, the photodetector 8 with gain multiplier and the signal synchronization and recording module 7 are placed together in the electromagnetic shielding box 6. The signal synchronization and recording module 7 is triggered by an optical synchronization signal, ensuring electrical insulation between the equipment inside the electromagnetic shielding box 6 and the external environment. This effectively solves the problem of the weak electromagnetic interference resistance of the multiplier photodetector 8. Compared to existing measurement systems, the use of a split-beam fiber bundle 12 to transmit visible light to the photodetector 8, along with placing both the photodetector 8 and the signal synchronization and recording module 7 (except for 19 which is in the box) within the electromagnetic shielding box 6, solves the electromagnetic sensitivity problem of the high-sensitivity photodetector to the test environment, improves the sensitivity of visible light power detection, and allows for a wider linear dynamic range of the detection system by matching the split-beam fiber bundle with photodetectors of different sensitivities.

[0057] The electromagnetic shielding box 6 includes an inner shielding box and an outer shielding box fitted over the inner shielding box. An insulating medium is provided between the inner and outer shielding boxes. The outer shielding box is used for proper grounding and is insulated from the photodetector 8, the high-voltage power supply unit 15, the data acquisition unit 16, and the 220V uninterruptible power supply 17. Both the inner and outer shielding boxes have multiple holes of different sizes for the output end of the split fiber bundle 12 and the single-mode dual-core fiber 23 to pass through. The size of the holes is determined according to the fiber diameter of the split fiber bundle 12 and should not be too large to ensure a good electromagnetic shielding effect. The inner shielding box and its internal equipment are all floating.

[0058] The working principle of the above embodiments is as follows:

[0059] Visible light emitted from the plasma radiation source 1 is directed onto a reflector 5 after passing through a third-order aperture 3. The reflector 5 is positioned at a 45° angle to the incident light beam. The incident end face of the split-type fiber bundle 12 is located on the outgoing light path of the reflector and is perpendicular to the direction of the incident visible light. The visible light reflected by the reflector is incident on the incident end face of the split-type fiber bundle 12. After being collected and transmitted in sections by the split-type fiber bundle 12, it is directed onto four photodetectors 8 with different gain ratios inside the electromagnetic shielding box 6. A visible light filter and a visible light attenuator are placed between the photodetectors 8 and the outgoing end of the split-type fiber bundle 12. The visible light signal is converted into an electrical signal by the photodetectors 8 and recorded by the data acquisition unit 16.

[0060] The synchronous electro-optic converter 19 converts the electrical signal output by the driving current generator of the plasma radiation source 1 under test into a synchronous optical signal; the synchronous photoelectric converter 18 converts the synchronous optical signal output by the synchronous electro-optic converter 19 into a synchronous electrical signal, and the characteristics of the electrical signal match the characteristics of the trigger electrical signal required by the data acquisition unit 16.

[0061] The present invention also provides a method for measuring visible light radiation power of plasma, comprising the following steps:

[0062] 1) Construct the aforementioned plasma visible light radiation power measurement system;

[0063] 2) Visible light and a trigger electrical signal are emitted from the plasma radiation source 1 to be tested. The visible light passes sequentially through the near-end aperture 9, the intermediate aperture 10, and the far-end aperture 11. The irradiation area of ​​the plasma radiation source 1 to be tested is selected by the near-end aperture 9 and the far-end aperture 11. The intermediate aperture 10 blocks the visible light outside the selected irradiation area from illuminating the reflector 5. The reflector 5 reflects the incident visible light. At the same time, the trigger electrical signal passes sequentially through the synchronous electro-optic converter 19, the synchronous photoelectric converter 18, and the data acquisition unit 16. The data acquisition unit 16 is triggered to record the output signal of the photodetector 8.

[0064] 3) Visible light signals are collected by a split-beam fiber bundle and transmitted to multiple photodetectors 8;

[0065] 4) The photodetector 8 converts visible light signals into electrical signals;

[0066] 5) The electrical signal is converted into a digital signal by the data acquisition unit 16 and sent to the storage module 20 for storage.

Claims

1. A plasma visible light radiation power measurement system, characterized in that, Includes a vacuum tube (2), an aperture (3), a quartz vacuum sealed window (4), a reflector (5), an electromagnetic shielding box (6), a signal synchronization and recording module (7), a photodetector (8), a split-type fiber bundle (12), a filter (13), an optical attenuator (14), and a storage module (20); The signal synchronization and recording module (7) includes a high-voltage power supply unit (15), a data acquisition unit (16), a 220V uninterruptible power supply (17), a synchronous photoelectric converter (18), and a synchronous electro-optic converter (19); The plasma radiation source (1) to be tested is located inside the front end of the vacuum pipe (2); the quartz vacuum sealing window (4) is located at the rear end of the vacuum pipe (2) and is coaxial with the vacuum pipe (2); the aperture (3) is used to select the irradiation area of ​​the plasma radiation source (1) to be tested and is located inside the vacuum pipe (2); the reflector (5) is located outside the vacuum pipe (2) and is at a 45° angle to the incident visible light beam emitted by the plasma radiation source (1) to be tested; the incident end of the split-type fiber bundle (12) is located at... In the outgoing light path of the reflector (5), the outgoing light from the outgoing end of the split-type fiber bundle (12) passes through the filter (13) and the optical attenuator (14) and enters the photodetector (8); the photodetector (8) has several photodetectors arranged in parallel; the photodetector (8), the filter (13), the optical attenuator (14), the high-voltage power supply unit (15), the data acquisition unit (16), the 220V uninterruptible power supply (17), and the synchronous photoelectric converter (18) are located in the electromagnetic shielding box (6); The photodetector (8) is connected to the data acquisition unit (16) via a signal cable (21); the plasma radiation source (1) to be measured is connected to the synchronous electro-optic converter (19) via a signal cable (21), the synchronous electro-optic converter (19) is connected to the synchronous photodetector (18) via a single-mode dual-core optical fiber (23), and the synchronous photodetector (18) is connected to the data acquisition unit (16) via a signal cable (21); the storage module (20) is connected to the data acquisition unit (16) via a single-mode dual-core optical fiber (23), and the data acquisition unit (16) is used to acquire the visible light radiation power of the plasma detected by the photodetector (8); the high-voltage power supply unit (15) is connected to the power supply end of the photodetector (8) via a high-voltage power supply cable (22) and is used to provide high voltage to the photodetector (8); the 220V uninterruptible power supply (17) is connected to the high-voltage power supply unit (15), the data acquisition unit (16) and the synchronous photodetector (18) respectively.

2. The plasma visible light radiation power measurement system according to claim 1, characterized in that, The aperture (3) is a three-level aperture, including a near-end aperture (9), an intermediate aperture (10), and a far-end aperture (11) arranged sequentially along the visible light emission direction of the plasma; The near-end aperture (9) and far-end aperture (11) are used to select the irradiation area of ​​the plasma radiation source (1) to be tested; the middle aperture (10) is used to block visible light outside the selected irradiation area from shining on the reflector (5). The inner diameters of the near-end aperture (9) and the far-end aperture (11) determine the size of the plasma irradiation area being targeted.

3. The plasma visible light radiation power measurement system according to claim 1, characterized in that, The aperture (3) is made of tungsten, and its thickness and aperture are both in the mm range.

4. The plasma visible light radiation power measurement system according to claim 1, characterized in that, The substrate of the reflector (5) is K9 glass, and the front surface of the substrate is coated with Al material, with the thickness of Al on the order of micrometers.

5. The plasma visible light radiation power measurement system according to claim 1, characterized in that, The split-type fiber bundle (12) is used to transmit the visible light reflected by the reflector (5) to the photodetector (8); The photodetector (8) consists of four photodetectors arranged in parallel, and the number of bundles in the split-type fiber bundle (12) is four; The incident end face of the split fiber bundle (12) is located on the outgoing light path of the reflector (5) and is perpendicular to the outgoing visible light direction of the reflector (5). The diameter of the incident end of the split-type fiber bundle (12) is determined by the source region size of the plasma radiation source (1) to be measured and the aperture of the aperture. The incident end of the split-type fiber bundle (12) includes a central circular region fiber (24), a spacer layer (25), and an outer ring region fiber (26); The output end of the split-type fiber bundle (12) includes a first output end, a second output end, a third output end and a fourth output end; The fiber cores of the central circular region fiber (24) are the same diameter, and the fiber cores are evenly distributed to the first output end and the second output end. The splitting ratios of the first output end and the second output end are the same. The fiber cores of the outer ring region fiber (26) are the same diameter, and the fiber cores are evenly distributed to the third output end and the fourth output end. The splitting ratios of the third output end and the fourth output end are the same. The spacer layer (25) is made of aluminum alloy.

6. The plasma visible light radiation power measurement system according to claim 5, characterized in that, The diameter of the central circular region at the incident end of the split-type fiber bundle (12) is 14 mm, the outer diameter of the aluminum alloy spacer layer is 19 mm, and the outer diameter of the outer annular region is 33.4 mm. The diameters of the first and second output terminals are both 10.4 mm, and the diameters of the third and fourth output terminals are both 21.3 mm.

7. The plasma visible light radiation power measurement system according to claim 1, characterized in that, The gain of the photodetector (8) is 1 to 1E5 and the response time is less than 3 ns.

8. The plasma visible light radiation power measurement system according to claim 1, characterized in that, The electromagnetic shielding box (6) includes an inner shielding box, an insulating medium, and an outer shielding box that are sequentially adjacent from the inside to the outside. The outer shielding enclosure is used for grounding; The electromagnetic shielding box (6) is provided with holes for the output end of the split-type fiber bundle (12) and the single-mode dual-core fiber (23) to pass through.

9. A method for measuring visible light radiation power of plasma, using the visible light radiation power measurement system of plasma according to any one of claims 1 to 8, characterized in that, include: The plasma radiation source (1) to be tested is placed inside the vacuum tube (2); When measuring the visible light radiation power of the plasma radiation source (1) under test, the plasma radiation source (1) under test emits visible light and trigger electrical signals; Visible light emitted from the plasma radiation source (1) is sequentially irradiated onto the reflector (5) through the aperture (3) and the quartz vacuum sealed window (4). The reflected light from the reflector (5) is sequentially transmitted to the photodetector (8) through the split-type fiber bundle (12), the filter (13), and the optical attenuator (14). The photodetector (8) converts the visible light signal into an electrical signal. The trigger electrical signal emitted by the plasma radiation source (1) is transmitted to the synchronous electro-optic converter (19) via the signal cable (21). The synchronous electro-optic converter (19) converts the trigger electrical signal into an optical signal. The optical signal converted by the synchronous electro-optic converter (19) is transmitted to the synchronous photoelectric converter (18) via the single-mode dual-core optical fiber (23). The synchronous photoelectric converter (18) converts the received optical signal into an electrical signal. The electrical signal converted by the synchronous photoelectric converter (18) is transmitted to the data acquisition unit (16). The trigger data acquisition unit (16) receives the electrical signal from the photodetector (8) and converts the electrical signal from the photodetector (8) into a digital signal and records it. The recorded digital signal is transmitted to the storage module (20) via the single-mode dual-core optical fiber (23) for storage.

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