High time-resolution X-ray imaging measurement instrument

Abstract

This invention discloses a high temporal resolution X-ray imaging measurement instrument, comprising a light-receiving imaging module, an X-ray optical conversion module, an interferometry module, a compression recording module, and a control and processing module. It not only enables high temporal resolution X-ray imaging measurement, but also differs from traditional X-ray streak cameras and X-ray framing cameras. The components placed inside the target chamber in this high temporal resolution X-ray imaging measurement instrument are all non-electronic optical elements. The optical streak camera and control and processing module, which are susceptible to radiation interference, can be placed far from the target chamber. The signal conversion and transmission in between are all optical processes. Therefore, this high temporal resolution X-ray imaging measurement instrument not only enables high spatiotemporal resolution X-ray imaging but also has excellent radiation resistance.

Description

Technical Field

[0001] This invention relates to the field of laser inertial confinement fusion technology, specifically to a high time-resolution X-ray imaging measurement instrument. Background Technology

[0002] Inertial confinement fusion is expected to become an effective way to cleanly utilize fusion energy in the future and has important research value.

[0003] The current mainstream approach used internationally is indirect-driven center ignition, which involves first forming a high-temperature, high-density hot spot at the center of the target pellet, where a fusion reaction occurs and self-sustaining combustion takes place. This process is accompanied by the emission and propagation of various signals, including optical, X-ray, and neutron signals. Experiments require spatiotemporal resolution measurements of these signals to analyze the reaction mechanisms and effects of each physical process.

[0004] X-ray diagnostics plays a crucial role in experimental research on laser inertial confinement fusion and high-energy-density physics. From laser injection to the generation of X-rays in the black cavity, to the inward compression of the target by X-ray ablation, and finally the formation of hot spots and the outward radiation of X-rays, X-rays play an important role. Diagnosing the spatiotemporal behavior of X-rays can characterize the state of many physical parameters such as implosion asymmetry and hot spot morphology, and reveal the hidden physical mechanisms and laws.

[0005] Currently, X-ray time-resolved imaging instruments mainly include X-ray streak cameras and X-ray framing cameras. While X-ray streak cameras possess high temporal resolution (~10 ps), they only offer one-dimensional spatial resolution. X-ray framing cameras, on the other hand, while possessing high spatial resolution, have poor temporal resolution (~16 frames, 70 ps time resolution). Therefore, neither existing X-ray streak cameras nor X-ray framing cameras can meet the demands of physics experiments for high spatiotemporal resolution X-ray diagnostics. Furthermore, both X-ray streak cameras and X-ray framing cameras contain ultra-high precision electro-optical components, but experiments require placement within a target chamber with a complex radiation environment, posing a significant risk of electromagnetic and ionizing radiation malfunctioning the electro-optical components.

[0006] Solving these problems is now a top priority. Summary of the Invention

[0007] To address the technical problems of existing X-ray time-resolved imaging instruments being unable to achieve high spatiotemporal resolution X-ray imaging diagnosis and having poor radiation resistance, this invention provides a high time-resolved X-ray imaging measurement instrument.

[0008] The technical solution is as follows:

[0009] A high time-resolution X-ray imaging measurement instrument, the key features of which are: a light-receiving imaging module, an X-ray optical conversion module, an interferometry module, a compression recording module, and a control and processing module;

[0010] The light-collecting imaging module includes a probe light source, a light-guiding fiber, and an imaging lens group one.

[0011] The X-ray optical conversion module includes a conversion component and a pinhole plate with pinholes. The conversion component includes a mask, a conversion body, a reflective film, and a filter that are sequentially attached toward the pinhole plate.

[0012] The compression recording module includes a digital micromirror array, an optical streak camera, and an imaging lens group two.

[0013] The control and processing module is used to synchronously control the probe light source and the optical stripe camera, and to process and analyze the information collected by the optical stripe camera.

[0014] X-rays emitted from the target are imaged onto a filter through a pinhole. After the filter performs energy region selection, the X-rays pass through a reflective film and enter a converter, where the refractive index of the converter carries information about the intensity changes of the X-rays. Simultaneously, a short-pulse probe light emitted from the probe source is transmitted through a light-guiding fiber and then through imaging lens group one to a mask. After passing through the mask and the converter in sequence, it is reflected by the reflective film. The reflected probe light carries information about the intensity changes of the X-rays in its phase. The probe light is then transmitted through imaging lens group one to an interferometer module. The interferometer module converts the phase changes of the probe light into an interferometric image with a time difference. The interferometric image with a time difference is first transmitted through imaging lens group two to a digital micromirror array for encoding. The encoded interferometric image with a time difference is then imaged through imaging lens group two onto the slit of an optical streak camera, where it is recorded.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] The high time-resolution X-ray imaging measurement instrument using the above technical solution emits X-rays from the target, images them through a pinhole to the converter, and then through an interferometer module to the final compression recording. The entire imaging process retains the spatial resolution information of the X-rays. Based on the ultrafast compression theory, the encoded compressed image is decoded and reconstructed to obtain a time-varying two-dimensional interferometric field. Then, based on the difference frequency interferometry principle, the time-varying phase field is obtained, and based on the photorefractive principle, the time-varying process of the X-ray spatial intensity is obtained. In other words, it can realize high time-resolution X-ray imaging measurement.

[0017] Unlike traditional X-ray streak cameras and X-ray framing cameras, the components placed inside the target chamber of this high time-resolution X-ray imaging measurement instrument are all non-electronic optical components. The optical streak camera and control processing module, which are susceptible to radiation interference, can be placed far away from the target chamber. The signal conversion and transmission in between are all optical processes. Therefore, this high time-resolution X-ray imaging measurement instrument can not only perform high spatiotemporal resolution imaging of X-rays, but also has excellent radiation resistance. Attached Figure Description

[0018] Figure 1 This is a schematic diagram illustrating the principle of the present invention. Detailed Implementation

[0019] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0020] like Figure 1 As shown, a high time-resolution X-ray imaging measurement instrument mainly includes a light-receiving imaging module 100, an X-ray optical conversion module 200, an interference module 300, a compression recording module 400, and a control processing module 500.

[0021] The light-receiving imaging module 100 includes a probe light source 101, a light-guiding fiber 102, and an imaging lens assembly one. The imaging lens assembly one includes a semi-transparent mirror 103 and lenses 104 and 105 positioned on either side of the semi-transparent mirror 103 along its transmission direction. Lens 104 is located between the semi-transparent mirror 103 and the light-guiding fiber 102, while lens 105 is located on the side of the semi-transparent mirror 103 furthest from lens 104. The imaging lens assembly one is composed entirely of non-electronic optical components, making it not only simple and reliable but also possessing excellent radiation resistance.

[0022] The short-pulse probe light in the visible light band emitted by the probe light source 101 is transmitted through the optical fiber 102 and then passes through lens 104, semi-transparent mirror 103 and lens 105 in sequence before being directed to the X-ray optical conversion module 200.

[0023] The X-ray optical conversion module 200 includes a conversion component 202 and a pinhole plate 201. The pinhole plate 201 has a pinhole 201a, enabling pinhole imaging. The conversion component 202 includes a mask 202a, a converter 202b, a reflective film 202c, and a filter 202d, which are sequentially attached towards the pinhole plate 201. The mask 202a is used to shield stray light other than the signal to be measured. The refractive index of the converter 202b changes with the intensity of X-rays, and this photorefractive effect has high spatiotemporal resolution (temporal resolution on the order of picoseconds, spatial resolution on the order of micrometers). In this embodiment, the converter 202b is preferably made of GaAs semiconductor devices, which have high conversion efficiency and strong anti-interference ability. The reflective film 202c is used to reflect probe light, while X-rays can pass through. In this embodiment, the reflective film 202c is preferably made of Al, which has high reflection efficiency and low cost. The filter 202d is used to select the energy region of X-rays. In this embodiment, the material of the filter 202d is preferably Be or Al, and the selection is made according to the energy region selection.

[0024] X-rays emitted from target 600 are imaged onto filter 202d through pinhole 201a. After energy region selection by filter 202d, they pass through reflective film 202c and enter converter 202b, causing the refractive index of converter 202b to carry the intensity change information of X-rays. At the same time, probe light emitted from lens 105 is transmitted to mask 202a, and then passes through mask 202a and converter 202b in sequence before being reflected by reflective film 202c. The phase of the reflected probe light carries the intensity change information of X-rays. Then, after passing through lens 105, the probe light is reflected by semi-transparent mirror 103 towards interference module 300.

[0025] The interference module 300 includes a second semi-transparent mirror 301, a third semi-transparent mirror 302, a first mirror 303 and a second mirror 304 disposed on both sides of the transmission direction of the second semi-transparent mirror 301, and a third mirror 305 and a fourth mirror 306 disposed on both sides of the transmission direction of the third semi-transparent mirror 302. A standard etalon 307 is disposed on the second mirror 304. By selecting the material and thickness of the standard etalon 307, the time difference between the two interference images can be precisely controlled.

[0026] Interference module 300 converts the phase change of the probe light into an interferometric image with a time difference. Specifically, the probe light carrying X-ray intensity change information in its phase emitted from the semi-transparent mirror 103 is reflected by mirror 303 and then directed to the semi-transparent mirror 301, where it is split into two. One beam is reflected from the semi-transparent mirror 301, then reflected by mirror 305, and directed to the semi-transparent mirror 302. After passing through the semi-transparent mirror 302, it is reflected by mirror 406 to the imaging mirror group 2. The other beam is transmitted from the semi-transparent mirror 301, delayed by etalon 307, then reflected by mirror 204 to the semi-transparent mirror 302, then reflected by the semi-transparent mirror 302 to mirror 406, and finally reflected by mirror 406 to the imaging mirror group 2.

[0027] The compression recording module 400 includes a digital micromirror array 401, an optical streak camera 402, and an imaging mirror group two. The main function of the compression recording module 400 is to encode and compress the time-varying two-dimensional interference field based on the principle of ultrafast compression imaging. That is, the interference image with time difference is first transmitted to the digital micromirror array 401 for encoding via the imaging mirror group two. The encoded interference image with time difference is then imaged sequentially by the imaging mirror group two onto the slit of the optical streak camera 402, where it is recorded.

[0028] The imaging lens group two includes a fifth mirror 403, a fifth lens 406, a sixth lens 407, a semi-transparent mirror 408, and a third lens 404 and a fourth lens 405 that together constitute the optical 4F system. The fifth mirror 403 and the digital micromirror array 401 are located on both sides of the transmission direction of the semi-transparent mirror 408, respectively. The third lens 404 and the fourth lens 405 are arranged sequentially between the fifth mirror 403 and the semi-transparent mirror 408. The fifth lens 406 is arranged between the digital micromirror array 401 and the semi-transparent mirror 408. The sixth lens 407 is arranged between the semi-transparent mirror 408 and the optical streak camera 402.

[0029] The time-difference interference image emitted from mirror 406 is sequentially transmitted through lens 304, lens 405, semi-transparent mirror 408, and lens 506, and then transmitted to the digital micromirror array 401 for encoding. The encoded time-difference interference image is first transmitted through lens 506, then reflected by semi-transparent mirror 408 to lens 607, and finally imaged by lens 607 onto the slit of optical fringe camera 402, where it is recorded. It should be noted that the slit of optical fringe camera 402 is fully open to acquire a two-dimensional image at each moment. Combined with the scanning deflection of the fringe camera, compressed recording of the two-dimensional interference image is achieved.

[0030] The control processing module 500 is used to synchronously control the probe light source 101 and the optical streak camera 402, and to process and analyze the information acquired by the optical streak camera 402. In other words, the main function of the control processing module 500 is to achieve timing synchronization control between the modules and to complete the data processing and analysis of the signals.

[0031] Therefore, X-rays emitted from the target 600 are imaged through the pinhole 201a to the converter 202b, and then through the interferometer module 300 to the final compression recording. The entire imaging process retains the spatial resolution information of the X-rays. Based on the ultrafast compression theory, the encoded compressed image is decoded and reconstructed to obtain the time-varying two-dimensional interferometric field. Then, based on the difference frequency interferometry principle, the time-varying phase field is obtained, and based on the photorefractive principle, the time-varying process of the X-ray spatial intensity is obtained. Thus, high time-resolution imaging measurement of X-rays can be achieved.

[0032] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention. Those skilled in the art, under the guidance of the present invention, can make various similar representations without departing from the spirit and claims of the present invention, and such modifications all fall within the protection scope of the present invention.

Claims

1. A high time-resolution X-ray imaging measurement instrument, characterized in that: It includes a light-receiving imaging module (100), an X-ray optical conversion module (200), an interference module (300), a compression recording module (400), and a control processing module (500); The light-collecting imaging module (100) includes a probe light source (101), a light guide fiber (102), and an imaging lens group one; The X-ray optical conversion module (200) includes a conversion component (202) and a pinhole plate (201) with pinholes (201a). The conversion component (202) includes a mask (202a), a conversion body (202b), a reflective film (202c), and a filter (202d) that are sequentially attached toward the pinhole plate (201). The conversion body (202b) is made of GaAs semiconductor device. The compression recording module (400) includes a digital micromirror array (401), an optical streak camera (402), and an imaging lens group two; The control processing module (500) is used to synchronously control the probe light source (101) and the optical stripe camera (402), and to process and analyze the information collected by the optical stripe camera (402). X-rays emitted from the target (600) are imaged onto a filter (202d) through a pinhole (201a). After energy region selection by the filter (202d), the X-rays pass through a reflective film (202c) and enter a converter (202b), causing the refractive index of the converter (202b) to carry information about the intensity change of the X-rays. Simultaneously, a short-pulse probe beam emitted from the probe light source (101) is transmitted through a light guide fiber (102) and then transmitted to a mask (202a) by the imaging lens group. After passing through the mask (202a) and the converter (202b) in sequence, the X-rays are imaged onto a filter (202d) through a pinhole (201a). The probe light is reflected by the film (202c), and the reflected probe light carries the intensity change information of X-rays in its phase. Then the probe light is transmitted to the interference module (300) via the imaging mirror group one. The interference module (300) converts the phase change of the probe light into an interference image with time difference. The interference image with time difference is first transmitted to the digital micromirror array (401) via the imaging mirror group two for encoding. The encoded interference image with time difference is then imaged by the imaging mirror group two onto the slit of the optical streak camera (402) and recorded by the optical streak camera (402).

2. The high time-resolution X-ray imaging measuring instrument according to claim 1, characterized in that: The imaging lens group includes a semi-transparent mirror (103) and a lens (104) and a lens (105) disposed on both sides of the semi-transparent mirror (103) in the transmission direction. The lens (104) is located between the semi-transparent mirror (103) and the optical fiber (102), and the lens (105) is located between the semi-transparent mirror (103) and the mask (202a).

3. The high time-resolution X-ray imaging measuring instrument according to claim 1, characterized in that: The interference module (300) includes a second semi-transparent mirror (301), a third semi-transparent mirror (302), a first mirror (303) and a second mirror (304) disposed on both sides of the transmission direction of the second semi-transparent mirror (301), and a third mirror (305) and a fourth mirror (306) disposed on both sides of the transmission direction of the third semi-transparent mirror (302). A standard (307) is provided on the second mirror (304). The probe light carrying X-ray intensity change information emitted from the imaging mirror group one is reflected by the first reflector (303) and then directed to the second semi-transparent mirror (301), and is split into two by the second semi-transparent mirror (301). One beam is reflected from the second semi-transparent mirror (301), then reflected by the third reflector (305) and directed to the third semi-transparent mirror (302), then passed through the third semi-transparent mirror (302) and reflected by the fourth reflector (306) to the imaging mirror group two. The other beam is transmitted from the second semi-transparent mirror (301), delayed by the etalon (307), then reflected by the second reflector (304) to the third semi-transparent mirror (302), then reflected by the third semi-transparent mirror (302) to the fourth reflector (306), and finally reflected by the fourth reflector (306) to the imaging mirror group two.

4. The high time-resolution X-ray imaging measuring instrument according to claim 1, characterized in that: The imaging mirror group two includes a fifth mirror (403), a fifth lens (406), a sixth lens (407), a fourth semi-transparent mirror (408), and a third lens (404) and a fourth lens (405) that together constitute the optical 4F system. The fifth mirror (403) and the digital micromirror array (401) are located on both sides of the transmission direction of the fourth semi-transparent mirror (408). The third lens (404) and the fourth lens (405) are arranged sequentially between the fifth mirror (403) and the fourth semi-transparent mirror (408). The fifth lens (406) is arranged between the digital micromirror array (401) and the fourth semi-transparent mirror (408). The sixth lens (407) is arranged between the fourth semi-transparent mirror (408) and the optical streak camera (402). Interference images with time difference emitted from the interference module (300) are transmitted sequentially through lens three (404), lens four (405), semi-transparent mirror four (408) and lens five (406), and transmitted to the digital micromirror array (401) for encoding. The encoded interference images with time difference are first transmitted through lens five (406), and then reflected by semi-transparent mirror four (408) to lens six (407), and then imaged by lens six (407) to the slit of the optical streak camera (402), and recorded by the optical streak camera (402).

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