Multi-branch simultaneous calibration device and method for transmittance of scattered light diagnosis system

Abstract

The invention discloses a multi-branch simultaneous calibration device and method for transmittance of a scattered light diagnostic system. The multi-branch simultaneous calibration device comprises a calibration light source, an optical fiber, a focusing lens, a diffuse scattering target, a workbench and a power meter. The diffuse scattering target is arranged in the center of the target chamber, and the calibration laser is focused to the diffuse scattering target through the optical fiber and the focusing lens through the target chamber light-transmitting window to generate uniform scattered light to cover a plurality of branches. A light receiving mirror assembly and a power meter are driven by a workbench to synchronously match a scattering light path, the light intensity is monitored in real time in combination with a second power meter, and the response efficiency of each branch is calculated based on the Lambert reflection principle. According to the invention, multi-branch synchronous calibration is realized, the problems of low efficiency and poor precision of the traditional method are solved, and the calibration speed and accuracy of the scattered light diagnosis system of the large-scale laser device are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of laser inertial confinement fusion experiment diagnosis, and more specifically, to a multi-branch simultaneous calibration device and method for the transmittance of a scattered light diagnosis system. Background Art

[0002] In laser inertial confinement fusion (ICF) and high energy density physics (HEDP) experiments, the accurate diagnosis of the backward scattered light energy is a key link in evaluating the process of laser-target matter interaction. Large laser devices usually configure multiple scattered light diagnosis branches (such as stimulated Brillouin scattering SBS, stimulated Raman scattering SRS, etc.), and periodic calibration is required to ensure the accuracy of the response efficiency of each branch. The traditional calibration method mainly relies on the fine laser beam calibration technology. The specific process is as follows: by using a target mirror or manually entering the target chamber to install an auxiliary laser, the fine laser beam is made to enter the diagnostic optical path in the reverse direction, and the total transmittance is measured using an energy meter. However, this method has significant defects: Insufficient spot coverage: The aperture of the fine laser beam is limited (usually in the millimeter range), and it cannot uniformly cover the incident laser components (the light passing aperture can reach the meter range), resulting in the transmittance of some areas not being effectively calibrated, introducing systematic errors.

[0003] High operation complexity: It is necessary to adjust the mirror angle or manually position the laser for each branch one by one, which is time-consuming and prone to introducing human errors. For a device with dozens of branches, the calibration period is as long as several days, seriously restricting the experimental efficiency.

[0004] Uneven light source intensity distribution: Even if the laser spot is expanded to cover the components, its Gaussian distribution characteristics are different from the uniform scattered light field in the experiment, resulting in the calibration results deviating from the actual working conditions.

[0005] In recent years, although some studies have tried to generate a calibration light source through a diffuser, limited by the geometric characteristics of the spot size and the distance to the target chamber, the traditional method still cannot solve the problem of multi-branch synchronous calibration. Therefore, there is an urgent need to develop a method that can quickly and accurately complete multi-branch synchronous on-line calibration to meet the high-efficiency experimental requirements of large laser devices. Summary of the Invention

[0006] The present invention aims to overcome the defects that the prior art cannot solve multi-branch simultaneous calibration, and the existing calibration methods are difficult to operate and have low calibration accuracy, and provides a multi-branch simultaneous calibration device and method for the transmittance of a scattered light diagnosis system.

[0007] To solve the above technical problems, the technical solution of the present invention is as follows: The present invention provides a multi-branch simultaneous calibration device for the transmittance of a scattered light diagnostic system, which includes a calibration light source, an optical fiber, a focusing lens, and a diffuse scattering target; the calibration light source, the optical fiber, and the focusing lens are sequentially coupled along the incident optical path; the diffuse scattering target is arranged in the central area of the target chamber and is surrounded by the target chamber wall, and a light-transmitting window is arranged on the target chamber wall; the focusing lens focuses the incident light beam generated by the calibration light source through the light-transmitting window onto the surface of the diffuse scattering target to form multiple backward scattering optical paths; Among them, an optical terminal, a light collection mirror assembly, an energy meter, a workbench, and a first power meter are arranged along the direction of the first backward scattering optical path. The optical terminal is used to capture scattered light; the light collection mirror assembly, the energy meter, and the first power meter are all arranged on the workbench, and the workbench drives the light collection mirror assembly, the energy meter, and the first power meter to match the first backward scattering optical path; A second power meter is arranged along the direction of the second backward scattering optical path to monitor the power of the scattered light in the second backward scattering optical path; A first electric baffle and a second electric baffle are further arranged on the target chamber wall; the first electric baffle is arranged on the light-transmitting window of the incident optical path between the focusing lens and the diffuse scattering target, and the second electric baffle is arranged on the light-transmitting window of the backward scattering optical path of the diffuse scattering target; both the first electric baffle and the second electric baffle are used to perform the on-off switching operation of the optical path of the corresponding light-transmitting window.

[0008] Preferably, the laser wavelengths output by the calibration light source include 351 nm and 532 nm, corresponding to the wavelengths of the first calibration mode and the second calibration mode respectively.

[0009] Preferably, a diffuse reflection coating is arranged on the surface of the diffuse scattering target to present the reflected light in a near-diffuse reflection state, and the incident light strikes the surface of the diffuse scattering target to form a circular light spot.

[0010] Preferably, the diameter D of the circular light spot and the working distance L from the center of the circular light spot to the optical terminal satisfy .

[0011] The present invention also provides a calibration method for the multi-branch simultaneous calibration device of the transmittance of the scattered light diagnostic system. The method includes: Move the energy meter out of the optical path to be calibrated through the workbench, and position the first power meter at the acquisition node of the optical path to be calibrated; Start the calibration light source and couple it to the optical fiber, and select the incident light of the corresponding wavelength according to the type of the branch to be calibrated; After the incident light is converged by the focusing lens, synchronously translate the second electric baffle to the optical path connection state, and the incident light enters the diffuse scattering target through the light-transmitting window of the target chamber wall; The incident light generates backward scattered light through the diffuse scattering target. Synchronously translate the first electric baffle to the optical path connection state. The backward scattered light reaches the second power meter, and the monitoring power of the monitoring calibration light is obtained by using the second power meter. The backward scattered light is transmitted to the first power meter of each branch through the optical terminals and light receiving mirror assemblies of each branch, and the calibration light power of the optical terminals and light receiving mirror assemblies of each branch is obtained. Substitute the monitoring power of the monitoring calibration light, the calibration light power of the optical terminals and light receiving mirror assemblies of each branch, the angle and solid angle between the optical terminal of each branch and the diffuse scattering target into the preset correlation expression to calculate the response efficiency of each branch. When the response efficiency in each branch reaches the preset response efficiency, the calibration operation of each branch is completed.

[0012] Preferably, the monitoring power of the monitoring calibration light is:

[0013] Wherein, is the calibration light power received by the second power meter; is the solid angle of the second power meter with respect to the diffuse scattering target; is the angle between the second power meter and the normal of the diffuse scattering target.

[0014] Preferably, the backward scattered light passes through the light receiving mirror assemblies of each branch to obtain the luminous intensity of the backward scattered light received by the light receiving mirror assemblies of each branch, specifically:

[0015] Wherein, is the angle between the measurement direction and the diffuse scattering target; is the luminous intensity per unit solid angle in the normal direction of the diffuse scattering target; is the angle between the diffuse scattering target and the normal is the luminous intensity per unit solid angle in the

[0016] Preferably, the calibration light power of the light receiving mirror assemblies of each branch is determined according to the luminous intensity of the backward scattered light received by the light receiving mirror assemblies, specifically: When the angle between the measurement direction and the diffuse scattering target is , the calibration light power of the light receiving mirror assemblies of each branch is:

[0017] When the solid angle between the light receiving mirror assembly and the diffuse scattering target is , the calibration light power of the light receiving mirror assemblies of each branch is:

[0018] Wherein, is the total calibration light power received by the light collection mirror assembly; is the value range of the light collection mirror assembly at the polar angle; is the azimuth angle of the light collection mirror assembly, and the azimuth angle of the light collection mirror assembly satisfies .

[0019] Preferably, the calibration light power of the backscattered light received by the optical terminal of the branch is:

[0020] wherein, is the calibration light power received by the th branch; is the solid angle of the th branch with respect to the diffuse scattering target; is the angle between the th branch and the normal of the diffuse scattering target; is the number of branches; is the calibration light power received by the second power meter; is the solid angle of the second power meter with respect to the diffuse scattering target; is the angle between the second power meter and the normal of the diffuse scattering target.

[0021] Preferably, the formula for the response efficiency of the branch is:

[0022] wherein, is the response efficiency of the th branch; is the calibration light power received by the th first power meter; is the number of branches; is the calibration light power received by the second power meter; is the solid angle of the second power meter with respect to the diffuse scattering target; is the angle between the second power meter and the normal of the diffuse scattering target.

[0023] Compared with the prior art, the beneficial effects of the technical solution of the present invention are: The present invention provides a multi-branch simultaneous calibration device and method for the transmittance of a scattered light diagnostic system. By means of an innovative multi-branch synchronous calibration method, the present invention solves the problems of low efficiency, poor accuracy, and complex operation of traditional calibration methods, and significantly improves the calibration efficiency and accuracy of the scattered light diagnostic system of a large laser device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic structural diagram of the multi-branch simultaneous calibration device for the transmittance of the scattered light diagnostic system described in Embodiment 1; Figure 2 It is a flowchart of the multi-branch simultaneous calibration method for the transmittance of the scattered light diagnostic system described in Embodiment 3.

[0025] Explanation of the reference numerals: 1. Calibration light source; 2. Optical fiber; 3. Focusing lens; 4. Diffuse scattering target; 5. Target chamber; 6. Target chamber wall; 7. Transparent window; 8. Optical terminal; 9. Light collection mirror assembly; 10. Energy meter; 11. Workbench; 12. First power meter; 13. Second power meter; 14. First electric baffle; 15. Second electric baffle. Detailed implementation manners

[0026] The accompanying drawings are only for illustrative purposes and should not be construed as limitations on this patent; To better illustrate this embodiment, some components in the accompanying drawings are omitted, enlarged or reduced, which do not represent the dimensions of the actual product; For those skilled in the art, it is understandable that some well-known structures and their descriptions in the accompanying drawings may be omitted.

[0027] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0028] Embodiment 1 This embodiment provides a multi-branch simultaneous calibration device for the transmittance of a scattered light diagnostic system, as Figure 1 shown, including a calibration light source 1, an optical fiber 2, a focusing lens 3 and a diffuse scattering target 4; the calibration light source 1, the optical fiber 2 and the focusing lens 3 are sequentially coupled along the incident optical path; the diffuse scattering target 4 is arranged in the central area of the target chamber 5 and is surrounded by the target chamber wall 6, and a transparent window 7 is arranged on the target chamber wall 6; the focusing lens 3 focuses the incident light beam generated by the calibration light source 1 onto the surface of the diffuse scattering target 4 through the transparent window 7 to form multiple backward scattering optical paths; Among them, an optical terminal 8, a light collection mirror assembly 9, an energy meter 10, a workbench 11 and a first power meter 12 are arranged along the direction of the first backward scattering optical path, and the optical terminal 8 is used to capture scattered light; the light collection mirror assembly 9, the energy meter 10 and the first power meter 12 are all arranged on the workbench 11, and the workbench 11 drives the light collection mirror assembly 9, the energy meter 10 and the first power meter 12 to perform three-dimensional translation to match the first backward scattering optical path; A second power meter 13 is arranged along the direction of the second backward scattering optical path to monitor the power of the scattered light in the second backward scattering optical path; A first electric baffle 14 and a second electric baffle 15 are further arranged on the target chamber wall 6; the first electric baffle 14 is arranged on the light transmission window 7 of the incident light path between the focusing lens 3 and the diffuse scattering target 4, and the second electric baffle 15 is arranged on the light transmission window 7 of the backward scattering light path of the diffuse scattering target 4; both the first electric baffle 14 and the second electric baffle 15 are used to perform the optical path on-off switching operation of the corresponding light transmission window 7.

[0029] Embodiment 2 This embodiment provides a multi-branch simultaneous calibration device for the transmittance of a scattered light diagnostic system, including a calibration light source 1, an optical fiber 2, a focusing lens 3 and a diffuse scattering target 4; the calibration light source 1, the optical fiber 2 and the focusing lens 3 are sequentially coupled along the incident light path; the diffuse scattering target 4 is arranged in the central area of the target chamber 5 and is surrounded by the target chamber wall 6, and a light transmission window 7 is arranged on the target chamber wall 6; the focusing lens 3 focuses the incident light beam generated by the calibration light source 1 onto the surface of the diffuse scattering target 4 through the light transmission window 7 to form a plurality of backward scattering light paths; Wherein, an optical terminal 8, a light receiving mirror assembly 9, an energy meter 10, a workbench 11 and a first power meter 12 are arranged along the first backward scattering light path direction, and the optical terminal 8 is used to capture scattered light; the light receiving mirror assembly 9, the energy meter 10 and the first power meter 12 are all arranged on the workbench 11, and the workbench 11 drives the light receiving mirror assembly 9, the energy meter 10 and the first power meter 12 to perform three-dimensional translation to match the first backward scattering light path; A second power meter 13 is arranged along the second backward scattering light path direction for monitoring the power of the scattered light in the second backward scattering light path; A first electric baffle 14 and a second electric baffle 15 are further arranged on the target chamber wall 6; the first electric baffle 14 is arranged on the light transmission window 7 of the incident light path between the focusing lens 3 and the diffuse scattering target 4, and the second electric baffle 15 is arranged on the light transmission window 7 of the backward scattering light path of the diffuse scattering target 4; both the first electric baffle 14 and the second electric baffle 15 are used to perform the optical path on-off switching operation of the corresponding light transmission window 7.

[0030] The laser wavelengths output by the calibration light source 1 include 351 nm and 532 nm, corresponding to the wavelengths of the first calibration mode and the second calibration mode respectively.

[0031] A diffuse reflection coating is arranged on the surface of the diffuse scattering target 4 for presenting the reflected light in a near-diffuse reflection state, and a circular light spot will be formed when the incident light strikes the surface of the diffuse scattering target 4; The diameter D of the circular light spot and the working distance L from the center of the circular light spot to the optical terminal 8 satisfy .

[0032] Embodiment 3 This embodiment also provides a multi-branch simultaneous calibration method for the transmittance of a scattered light diagnostic system, which is applied to the multi-branch simultaneous calibration device for the transmittance of the scattered light diagnostic system, as Figure 2 shown. The method includes: Move the energy meter 10 out of the optical path to be calibrated through the workbench 11, and position the first power meter 12 at the acquisition node of the optical path to be calibrated; Start the calibration light source 1 and couple it to the optical fiber 2. Select the output wavelength according to the type of the branch to be calibrated. When calibrating the stimulated Brillouin scattering branch, the incident light with a wavelength of 351 nm is output; when calibrating the stimulated Raman scattering branch, the incident light with a wavelength of 532 nm is output; After the incident light is converged by the focusing lens 3, synchronously translate the second electric baffle 15 to the optical path connection state, and the incident light enters the diffuse scattering target 4 through the light transmission window 7 of the target chamber wall 6; The incident light generates backward scattered light through the diffuse scattering target 4. Synchronously translate the first electric baffle 14 to the optical path connection state, and the backward scattered light reaches the second power meter 13. Use the second power meter 13 to obtain the monitoring power of the monitoring calibration light; The backward scattered light is transmitted to the first power meter 12 of each branch through the optical terminals 8 and the light receiving mirror assemblies 9 of each branch, and the calibration light power of the optical terminals 8 and the light receiving mirror assemblies 9 of each branch is obtained; Substitute the monitoring power of the monitoring calibration light, the calibration light power of the optical terminals 8 and the light receiving mirror assemblies 9 of each branch, the included angle and solid angle between the optical terminal 8 of each branch and the diffuse scattering target 4 into the preset correlation expression to calculate the response efficiency of each branch; When the response efficiency in each branch reaches the preset response efficiency, complete the calibration operation of each branch.

[0033] The monitoring power of the monitoring calibration light is:

[0034] Where is the calibration light power received by the second power meter; is the solid angle of the second power meter with respect to the diffuse scattering target; is the included angle between the second power meter and the normal of the diffuse scattering target.

[0035] The backward scattered light passes through the light receiving mirror assemblies 9 of each branch to obtain the luminous intensity of the backward scattered light received by the light receiving mirror assemblies 9 of each branch. Specifically:

[0036] Where is the included angle between the measurement direction and the diffuse scattering target; is the luminous intensity per unit solid angle in the normal direction of the diffuse scattering target; Is the angle between the diffuse scattering target and the normal The luminous intensity per unit solid angle in the direction.

[0037] Determine the calibrated optical power of each branch light collector assembly 9 according to the luminous intensity of the backward scattered light received by the light collector assembly 9. Specifically:[[]] When the angle between the measurement direction and the diffuse scattering target is The calibrated optical power of each branch light collector assembly 9 is:[[]]

[0038] When the solid angle between the light collector assembly 9 and the diffuse scattering target 4 is The calibrated optical power of each branch light collector assembly 9 is:[[]]

[0039] Among them, Is the total calibrated optical power received by the light collector assembly; Is the value range of the light collector assembly at the polar angle; Is the azimuth angle of the light collector assembly. The azimuth angle of the light collector assembly Satisfy .

[0040] The light intensity in the normal direction is:[[]]

[0041] The calibrated optical power of the backward scattered light received by the optical terminal 8 in the branch where it is located is:[[]]

[0042] Among them, Is the Th calibrated optical power received by the th branch; Is the Th solid angle of the th branch with respect to the diffuse scattering target; Is the Th angle between the th branch and the normal of the diffuse scattering target; Is the number of branches; Is the calibrated optical power received by the second power meter; Is the solid angle of the second power meter with respect to the diffuse scattering target; Is the angle between the second power meter and the normal of the diffuse scattering target.

[0043] The formula for the response efficiency of the branch where it is located is:[[]]

[0044] Among them, Is the Th response efficiency of the th branch; Is the The calibrated optical power received by the first power meter; is the number of branches; is the calibrated optical power received by the second power meter; is the solid angle of the second power meter with respect to the diffuse scattering target; is the angle between the second power meter and the normal of the diffuse scattering target.

[0045] The same or similar reference numerals correspond to the same or similar components; The terms describing the positional relationship in the drawings are for illustrative purposes only and should not be construed as limiting the present patent; Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all the embodiments here. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A multi-branch simultaneous calibration device for the transmittance of a scattered light diagnostic system, characterized in that It includes a calibration light source (1), an optical fiber (2), a focusing lens (3), and a diffuse scattering target (4); the calibration light source (1), the optical fiber (2), and the focusing lens (3) are sequentially coupled along the incident optical path; the diffuse scattering target (4) is arranged in the central area of the target chamber (5) and is surrounded by the target chamber wall (6), and a light-transmitting window (7) is arranged on the target chamber wall (6); the focusing lens (3) focuses the incident light beam generated by the calibration light source (1) through the light-transmitting window (7) onto the surface of the diffuse scattering target (4) to form multiple backward scattering optical paths. Among them, an optical terminal (8), a light collection mirror assembly (9), an energy meter (10), a workbench (11), and a first power meter (12) are arranged along the direction of the first backward scattering optical path. The optical terminal (8) is used to capture scattered light; the light collection mirror assembly (9), the energy meter (10), and the first power meter (12) are all arranged on the workbench (11), and the workbench (11) drives the light collection mirror assembly (9), the energy meter (10), and the first power meter (12) to match the first backward scattering optical path. A second power meter (13) is arranged along the direction of the second backward scattering optical path for monitoring the power of the scattered light in the second backward scattering optical path. A first electric baffle (14) and a second electric baffle (15) are also arranged on the target chamber wall (6); the first electric baffle (14) is arranged on the light-transmitting window (7) of the incident optical path between the focusing lens (3) and the diffuse scattering target (4), and the second electric baffle (15) is arranged on the light-transmitting window (7) of the backward scattering optical path of the diffuse scattering target (4); both the first electric baffle (14) and the second electric baffle (15) are used to perform the on-off switching operation of the optical path of the corresponding light-transmitting window (7).

2. The multi-branch simultaneous calibration device for the transmittance of the scattered light diagnostic system according to claim 1, wherein The laser wavelengths output by the calibration light source (1) include 351 nm and 532 nm, corresponding to the wavelengths of the first calibration mode and the second calibration mode respectively.

3. The multi-branch simultaneous calibration device for the transmittance of the scattered light diagnosis system according to claim 1, wherein, A diffuse reflection coating is arranged on the surface of the diffuse scattering target (4) for presenting the reflected light in a near-diffuse reflection state, and the incident light strikes the surface of the diffuse scattering target (4) to form a circular light spot.

4. The multi-branch simultaneous calibration device for the transmittance of the scattered light diagnosis system according to claim 3, characterized in that, The diameter D of the circular light spot and the working distance L from the center of the circular light spot to the optical terminal (8) satisfy .

5. A multi-branch simultaneous calibration method for the transmittance of a scattered light diagnostic system, characterized in that, The method is applied to the multi-branch simultaneous calibration device for the transmittance of the scattered light diagnosis system according to any one of claims 1 to 4, and includes: Move the energy meter (10) out of the optical path to be calibrated through the workbench (11), and position the first power meter (12) at the acquisition node of the optical path to be calibrated. Start the calibration light source (1) and couple it to the optical fiber (2), and select the incident light of the corresponding wavelength according to the type of the branch to be calibrated. After the incident light is converged by the focusing lens (3), synchronously translate the second electric baffle (15) to the optical path connection state, and the incident light enters the diffuse scattering target (4) through the light-transmitting window (7) of the target chamber wall (6). The incident light generates backward scattered light through the diffuse scattering target (4), synchronously translate the first electric baffle (14) to the optical path connection state, the backward scattered light reaches the second power meter (13), and the monitoring power of the calibration light is obtained by using the second power meter (13). The backward scattered light is transmitted to the first power meter (12) of each branch through the optical terminals (8) and light receiving mirror assemblies (9) of each branch to obtain the calibrated optical power of the optical terminals (8) and light receiving mirror assemblies (9) of each branch; According to the monitored power of the monitored calibration light, the calibrated optical power of the optical terminals (8) and light receiving mirror assemblies (9) of each branch, the included angle and solid angle between the optical terminal (8) of each branch and the diffuse scattering target (4), substitute them into the preset correlation expression to calculate the response efficiency of each branch; When the response efficiency in each branch reaches the preset response efficiency, the calibration operation of each branch is completed.

6. The multi-branch simultaneous calibration method for the transmittance of the scattered light diagnostic system according to claim 5, characterized in that, The monitored power of the monitored calibration light is: Wherein, is the calibrated optical power received by the second power meter; is the solid angle of the second power meter with respect to the diffuse scattering target; is the angle between the second power meter and the normal of the diffuse scattering target.

7. The multi-branch simultaneous calibration method for the transmittance of the scattered light diagnostic system according to claim 5, characterized in that The backward scattered light passes through the light receiving mirror assemblies (9) of each branch to obtain the luminous intensity of the backward scattered light received by the light receiving mirror assemblies (9) of each branch. Specifically: wherein, is the angle between the measurement direction and the diffuse scattering target; is the luminous intensity per unit solid angle in the direction of the normal of the diffuse scattering target; is the angle between the diffuse scattering target and the normal is the luminous intensity per unit solid angle in the direction.

8. The multi-branch simultaneous calibration method for the transmittance of the scattered light diagnostic system according to claim 7, characterized in that, Determine the calibrated optical power of the light receiving mirror assemblies (9) of each branch according to the luminous intensity of the backward scattered light received by the light receiving mirror assemblies (9). Specifically: When the included angle between the measurement direction and the diffuse scattering target (4) is , the calibrated optical power of each branch light receiving mirror assembly (9) is: When the solid angle between the light-receiving lens assembly (9) and the diffuse scattering target (4) is , the calibrated optical power of each branch light-receiving lens assembly (9) is: Wherein, is the total calibration light power received by the light collecting mirror assembly; is the value range of the light collecting mirror assembly at the polar angle; is the azimuth angle of the light collecting mirror assembly, and the azimuth angle of the light collecting mirror assembly satisfies .

9. The multi-branch simultaneous calibration method for the transmittance of the scattered light diagnostic system according to claim 5, characterized in that, The calibrated optical power of the backward scattered light received by the optical terminal (8) of the branch where it is located is: Wherein, is the calibrated optical power received by the th branch; is the solid angle of the th branch with respect to the diffuse scattering target; is the angle between the th branch and the normal of the diffuse scattering target; is the number of branches; is the calibrated optical power received by the second power meter; is the solid angle of the second power meter with respect to the diffuse scattering target; is the angle between the second power meter and the normal of the diffuse scattering target.

10. The multi-branch simultaneous calibration method for the transmittance of the scattered light diagnostic system according to claim 5, wherein The formula for the response efficiency of the branch where it is located is: Among them, is the response efficiency of the th branch; is the calibrated optical power received by the th first power meter; is the number of branches; is the calibrated optical power received by the second power meter; is the solid angle of the second power meter with respect to the diffuse scattering target; is the angle between the second power meter and the normal of the diffuse scattering target.

Images