CN220455609U

CN220455609U - Thomson scattering-oriented vacuum cavity internal follow-up light path

Info

Publication number: CN220455609U
Application number: CN202321886730.7U
Authority: CN
Inventors: 叶孜崇; 杨雄; 靳琛垚; 程谋森; 江堤; 郭大伟; 张炜; 李小康
Original assignee: National University of Defense Technology; Hefei Institutes of Physical Science of CAS
Current assignee: National University of Defense Technology; Hefei Institutes of Physical Science of CAS
Priority date: 2023-07-18
Filing date: 2023-07-18
Publication date: 2024-02-06
Anticipated expiration: 2033-07-18

Abstract

The application provides a follow-up light path in vacuum chamber towards thomson scattering, including laser income light path system, laser termination system and scattered light collecting system, wherein: the laser light-in light path system comprises a laser guiding device and a first electric cylinder, wherein the first electric cylinder is arranged on one side of a plasma main cavity, the input end of the laser guiding device is used for introducing laser, and the output end of the laser guiding device is arranged on a moving part of the first electric cylinder, so that the position of the laser entering the plasma from one side of the plasma main cavity is adjustable; the laser termination system comprises a laser terminator and a second electric cylinder, wherein the second electric cylinder is oppositely arranged on the other side of the plasma main cavity and is parallel to the first electric cylinder, and the laser terminator is arranged on a moving part of the second electric cylinder and synchronously moves with the output end of the laser guiding device on the first electric cylinder; the scattered light collecting system comprises a collecting lens group and a third electric cylinder, wherein the collecting lens group is arranged on a moving part of the third electric cylinder, moves synchronously with the output ends of the laser terminator and the laser guiding device and is used for collecting spectrum signals emitted by the action of laser and plasma.

Description

Thomson scattering-oriented vacuum cavity internal follow-up light path

Technical Field

The application relates to the technical field of optical detection, in particular to a follow-up light path in a vacuum cavity facing thomson scattering.

Background

The existing Thomson Scattering (TS) diagnosis is mainly fixed-point diagnosis, and even if the space resolution diagnosis is used, the existing TS diagnosis is realized by arranging the light receiving optical paths at multiple points, so that the existing TS diagnosis does not consider the problem of the movable optical paths. With the application of low-temperature plasma-oriented high-spatial-temporal resolution TS diagnosis, we face the problem of movable light paths.

The core of the requirement of the movable light path is that in the related basic research and engineering test, the implementation of space resolution diagnosis by arranging a plurality of lasers is not feasible in cost, the time average power of general pulse TS diagnosis laser reaches 10W, optical termination is required to be arranged after the laser rays pass through a diagnosis space, otherwise, the laser strikes uncontrollable stray scattering on a cavity not only threatens the photosensitive element of TS diagnosis and other optical diagnosis, but also forms direct safety threat to experimenters. With continuous light TS diagnosis, the laser continuous power reaches 100W or even 1000W, and in this case, optical termination is indispensable.

In general, a tapered cylindrical laser terminator (or light cone, hereinafter terminator) is an ideal optical terminator because the ring light axially traps the light for termination. However, if the laser is movable and the optical terminator is not follower, the laser spot will obviously deviate from the position of the optical terminator, resulting in the optical terminator being disabled. In addition, in the case of using a laser of 100W or more, the process of introducing the laser into the vacuum chamber itself presents a safety risk, because the laser is to be driven into the chamber from the laser, placing the laser and the entire laser path into the vacuum chamber itself is not feasible in terms of cost and technology, and the laser of 100W or more is actually difficult to directly couple into the chamber using an optical fiber, so that the laser must be introduced into the chamber with an extremely high light transmission quartz window, regardless of the window protection (if the coverage is too large, the window is easily blackened by the sputtered material generated by the plasma), and the design of multiple windows incident/exiting the plasma is not supported, regardless of the cost angle, or the residual reflection of the laser irradiated onto the window. Therefore, it is desirable to have a single window that is designed to be remote from the plasma sputter and then to allow the laser path to be moved through the movable mirror assembly within the vacuum chamber.

Finally, since the placement of multiple view points on a small device is not desirable for high spatial resolution purposes and cost effectiveness, the follow-up of the receive light path with the laser light path is also necessary.

Disclosure of Invention

The application provides a thomson scattering-oriented vacuum cavity internal follow-up light path, which aims to solve the technical problems of potential safety hazard, high cost and high technical difficulty of the existing thomson scattering-diagnosed laser light path.

The technical scheme adopted by the application is as follows:

a thomson scattering-oriented follow-up light path in a vacuum cavity comprises a laser light-in light path system, a laser termination system and a scattered light collection system, wherein:

the laser light-in light path system comprises a laser guiding device and a first electric cylinder, wherein the first electric cylinder is arranged on one side of a plasma main cavity, the input end of the laser guiding device is used for introducing laser, and the output end of the laser guiding device is arranged on a moving part of the first electric cylinder, so that the position of the laser entering the plasma from one side of the plasma main cavity is adjustable;

the laser termination system comprises a laser terminator and a second electric cylinder, wherein the second electric cylinder is oppositely arranged on the other side of the plasma main cavity and is parallel to the first electric cylinder, and the laser terminator is arranged on a moving part of the second electric cylinder and synchronously moves with the output end of the laser guiding device on the first electric cylinder;

the scattered light collecting system comprises a collecting lens group and a third electric cylinder, wherein the collecting lens group is arranged on a moving part of the third electric cylinder, moves synchronously with the output ends of the laser terminator and the laser guiding device and is used for collecting spectrum signals emitted by the action of laser and plasma.

Further, the laser guiding device comprises a light inlet window, a guiding lens group, a starting lens and a movable lens,

the light inlet window has light transmittance and is used for introducing laser;

the guiding lens group and the initial lens change the laser trend through reflection, so that the introduced laser is reflected for ninety degrees twice and then irradiates on the movable lens;

the movable lens is movably arranged on the moving part of the first electric cylinder, so that the laser is incident to the position of the plasma from one side of the plasma main cavity in a position-adjustable way.

Further, the laser guiding device further includes a focusing mirror that focuses the incident laser light.

Further, the movable lens reflecting surface adopts a concave reflecting mirror.

Further, the laser guiding device comprises a first electric cylinder, an optical fiber through hole, an optical fiber and an optical fiber coupler, wherein the optical fiber coupler is movably arranged on a moving part of the first electric cylinder, so that laser is incident to a plasma from one side of a plasma main cavity in a position-adjustable manner, and the optical fiber is connected and arranged between the optical fiber coupler and the optical fiber through hole and used for guiding the laser to the optical fiber coupler from the optical fiber through hole.

Further, the laser terminator adopts a conical terminator or a knife lamination terminator.

Further, the laser termination system further comprises a thermometer or a photoelectric sensor and a penetrating flange, wherein the thermometer or the photoelectric sensor is arranged on the laser terminator and is connected with an external device circuit through the penetrating flange, and the thermometer or the photoelectric sensor is used for detecting residual light after laser enters the laser terminator or heating temperature of the laser terminator.

Further, the laser termination system further comprises a water cooling pipe connected with the laser terminator and used for cooling the laser terminator.

Further, the laser light-in light path system and the laser termination system are both arranged in the sealed plasma main cavity;

or,

the laser light-in light path system and the laser termination system are respectively arranged in two independent vacuum cavities, and only the minimum opening width for ensuring laser passing is arranged between each independent vacuum cavity and the plasma main cavity.

Further, the collecting lens group comprises two lenses which are coaxially arranged, and a pinhole is arranged between the two lenses to form double-lens pinhole imaging.

Compared with the prior art, the application has the following beneficial effects:

the utility model provides a follow-up light path in vacuum chamber towards thomson scattering, including laser income light path system, laser termination system and scattered light collecting system, laser income light path system and laser termination system, this application simple structure, safe and reliable, with low costs, optical terminator also can follow-up when laser is movable, avoid the position of laser facula skew optical terminator, ensure that the terminator plays the effect, simultaneously, because arrange a plurality of observation points on the small-size device and do not accord with high spatial resolution's purpose and cost-effectiveness, therefore scattered light collecting system and laser income light path system, laser termination system also keep following, ensure that scattered light collecting system can carry out effective collection to scattered light, the accurate collection laser with plasma looks effect the spectral signal that sends.

In addition to the objects, features, and advantages described above, there are other objects, features, and advantages of the present application. The present application will be described in further detail with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application, illustrate and explain the application and are not to be construed as limiting the application. In the drawings:

fig. 1 is a schematic diagram of the composition of a follower light path in a vacuum chamber facing thomson scattering in a preferred embodiment of the present application.

Fig. 2 is a schematic diagram of the composition of a follower light path in a vacuum chamber facing thomson scattering according to another preferred embodiment of the present application.

Fig. 3 is a schematic structural view of the collection lens assembly 11 of the present application.

In the figure: 1. a light inlet window; 2. a guide mirror group; 3. starting a lens; 4. a movable lens; 5. a first electric cylinder; 6. a laser terminator; 7. a second electric cylinder; 8. a thermometer or a photoelectric sensor; 9. a water-cooled water pipe; 10. a through flange; 11. collecting a lens group; 12. a third electric cylinder; 13. the optical fiber is communicated; 14. an optical fiber; 15. an optical fiber coupler; 16. a lens; 17. a pinhole.

Detailed Description

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

Referring to fig. 1, a preferred embodiment of the present application provides a thomson scattering-oriented vacuum cavity follow-up optical path, including a laser light-in optical path system, a laser light-out system, and a scattered light collecting system, wherein:

the laser light-in light path system comprises a laser guiding device and a first electric cylinder 5, wherein the first electric cylinder 5 is arranged on one side of a plasma main cavity, the input end of the laser guiding device is used for introducing laser, and the output end of the laser guiding device is arranged on a moving part of the first electric cylinder 5, so that the laser is incident to the position of plasma from one side of the plasma main cavity in a position-adjustable manner;

the laser termination system comprises a laser terminator 6 and a second electric cylinder 7, wherein the second electric cylinder 7 is oppositely arranged on the other side of the plasma main cavity and is parallel to the first electric cylinder 5, and the laser terminator 6 is arranged on a moving part of the second electric cylinder 7 and synchronously moves with the output end of the laser guiding device on the first electric cylinder 5;

the scattered light collecting system comprises a collecting lens group 11 and a third electric cylinder 12, wherein the collecting lens group 11 is arranged on a moving part of the third electric cylinder 12, moves synchronously with the laser terminator 6 and the output end of the laser guiding device and is used for collecting spectrum signals emitted by the interaction of laser and plasma.

Preferably, the laser guiding device comprises a light inlet window 1, a guiding lens group 2, a starting lens 3 and a movable lens 4,

the light inlet window 1 has light transmittance for introducing laser;

the guiding lens group 2 and the initial lens 3 change the laser trend through reflection, so that the introduced laser is reflected for ninety degrees twice and then irradiates on the movable lens 4;

the movable lens 4 is movably arranged on a moving part of the first electric cylinder 5, so that the laser is incident to the plasma from the side of the plasma main cavity in a position adjustable manner.

Preferably, the laser light guiding device further includes a focusing mirror focusing the incident laser light.

Preferably, the reflecting surface of the movable lens 4 adopts a concave reflecting mirror.

Preferably, as shown in fig. 2, the laser guiding device comprises a first electric cylinder 5, an optical fiber through 13, an optical fiber 14 and an optical fiber coupler 15, wherein the optical fiber coupler 15 is movably arranged on a moving part of the first electric cylinder 5, so that the position of the laser is adjustably incident to the plasma from one side of a main plasma cavity, and the optical fiber 14 is connected and arranged between the optical fiber coupler 15 and the optical fiber through 13 and is used for guiding the laser to the optical fiber coupler 15 from the optical fiber through 13.

Preferably, the laser terminator 6 is a conical terminator or a knife stack terminator.

Preferably, the laser termination system further comprises a thermometer or a photoelectric sensor 8 and a penetrating flange 10, wherein the thermometer or the photoelectric sensor 8 is arranged on the laser terminator 6, and is connected with an external device circuit through the penetrating flange 10 and used for detecting residual light after laser enters the laser terminator 6 or heating temperature of the laser terminator 6.

Preferably, the laser termination system further comprises a water cooling pipe 9 connected to the laser terminator 6 for cooling the laser terminator 6.

Preferably, the laser light-in light path system and the laser termination system are both arranged in the sealed plasma main cavity;

or,

Preferably, as shown in fig. 3, the collecting lens group 11 includes two lenses 16 coaxially disposed, and a pinhole 17 is disposed between the two lenses 16 to form a dual-lens pinhole image.

The vacuum cavity follow-up optical path facing thomson scattering in the above embodiment includes three parts: the laser light-in light path system, the laser termination system and the scattered light collection system. The plasma device can be installed in the plasma device by adding a special vacuum cavity, and can be directly installed in the cavity under the condition that the space of the device is enough. When the self-independent vacuum cavity is used, the incident light path system should compress the area of the incident light path system which is open to the plasma main cavity, and only enough open width is reserved to ensure safe passing of laser so as to inhibit the condition that a sputtering object is coated on a lens group of the incident system.

Laser light enters the vacuum chamber from the light entrance window 1, which requires an ultra high light transmission window to minimize laser light scattering and the resulting personnel hazards. In order to reduce the problem of coating of the sputtered material, in the conditions of device condition permission and the condition that a laser incidence system uses an independent vacuum cavity, an incidence window is drawn from the cavity by one section as shown in the figure, one section of cavity reaching the window from a main vacuum cavity is reduced according to the size of a light spot, the condition permission can add water cooling to the section of cavity, and the deposition amount of the sputtered material passing through the cavity is increased by cooling to further protect the window from being coated.

After entering the vacuum chamber, the laser light is guided through a set of guiding mirrors 2 (single lens or periscope), a starting lens 3, the starting lens 3 being coaxial with the movable lens 4 and reflecting the laser light to the movable lens 4.4. The movable lens is erected and then is movable on the electric cylinder of the incident lens 5. The starting lens 3 and the movable lens 4 are coaxial, so that laser always strikes the movable lens 4 and is reflected in the same direction in the whole moving process of the movable lens 4, and the movable lens 4 only controls the position of the laser incident to the plasma so far, and does not change the incident angle of the laser. If focusing is needed, a focusing lens can be added in front of the periscope, or the movable lens 4 can be made into a concave lens.

When the high-power optical fiber condition permits, the incident light path can be simplified into optical fiber entering, and can be reflected to the movable lens in a free light form in the vacuum cavity, or can be erected into an integrated light path lens group which is unified and movable on the electric cylinder, and a focusing lens can be added as required.

Opposite the incident light path, a follow-up laser terminator 6 is provided, which is mainly used in this patent, but can also be replaced by a blade stack as required. The terminator is mounted on the second electric cylinder 7 (vacuum electric cylinder or other movable structure) for movement and is provided with water-cooled protection. After the terminator, a thermometer or a photoelectric sensor 8 can be added to detect the residual light after the laser enters the terminator or the temperature for heating the terminator, so as to ensure that the terminator receives the laser indeed. If the sensor does not detect the laser, a mechanism for closing the laser is triggered, and the laser is closed, so that safety is ensured. The power supply, signal wires and the like of the sensor, the water cooling pipeline and the motor are all led to the through flange 10 at the edge of the cavity for electric and water connection.

Since the laser light path is followed, the collecting light path also needs to be followed, so the collecting lens group is also placed on a collecting lens group electric cylinder to realize movement. The collecting lens group is arranged in the movable direction of the laser light path, so that the movable diagnosis is realized without adding a vertical long window, and the requirement of space distribution diagnosis can be met by only moving a round window along the facing direction of the window. Meanwhile, the lens group used in the patent uses the double lenses and the pinhole to image, and the diagnosis space is limited to the diameter of a light spot after laser focusing through the pinhole aperture, so that the depth of field is increased while peripheral stray light is compressed, and the fault tolerance of light path alignment is increased while the precision is increased. Of course, if this orientation does not allow for such a design, we could also change the position of the collection barrel to be parallel to the laser path or to be placed on top of the movable slide of the laser path or terminator.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present application without departing from the spirit or scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims and the equivalents thereof, the present application is intended to cover such modifications and variations.

Claims

1. The utility model provides a follow-up light path in vacuum chamber towards thomson scattering which characterized in that includes laser income light path system, laser termination system and scattered light collection system, wherein:

the laser light-in light path system comprises a laser guiding device and a first electric cylinder (5), wherein the first electric cylinder (5) is arranged on one side of a plasma main cavity, the input end of the laser guiding device is used for introducing laser, and the output end of the laser guiding device is arranged on a moving part of the first electric cylinder (5), so that the laser is incident to the position of plasma from one side of the plasma main cavity in a position-adjustable manner;

the laser termination system comprises a laser terminator (6), a second electric cylinder (7), wherein the second electric cylinder (7) is oppositely arranged on the other side of the plasma main cavity and is parallel to the first electric cylinder (5), and the laser terminator (6) is arranged on a moving part of the second electric cylinder (7) and synchronously moves with the output end of the laser guiding device on the first electric cylinder (5);

the scattered light collecting system comprises a collecting lens group (11) and a third electric cylinder (12), wherein the collecting lens group (11) is arranged on a moving part of the third electric cylinder (12), moves synchronously with the laser terminator (6) and the output end of the laser guiding device and is used for collecting spectrum signals emitted by the interaction of laser and plasma.

2. The optical path of the optical follow-up in the vacuum chamber facing thomson scattering according to claim 1, wherein the laser guiding device comprises an optical inlet window (1), a guiding lens group (2), a starting lens (3) and a movable lens (4),

the light inlet window (1) has light transmittance for introducing laser;

the guiding lens group (2) and the initial lens (3) change the trend of laser through reflection, so that the introduced laser is reflected by ninety degrees twice and then irradiates on the movable lens (4);

the movable lens (4) is movably arranged on the moving part of the first electric cylinder (5), so that the laser is incident to the plasma from one side of the plasma main cavity in a position-adjustable way.

3. The thomson scattering oriented vacuum chamber follow-up optical path of claim 2 wherein the laser directing means further comprises a focusing mirror for focusing the incident laser light.

4. The optical path according to claim 2, wherein the reflecting surface of the movable lens (4) is a concave reflecting mirror.

5. The optical path according to claim 1, characterized in that the laser guiding device comprises a first electric cylinder (5), an optical fiber through (13), an optical fiber (14) and an optical fiber coupler (15), wherein the optical fiber coupler (15) is movably arranged on a moving part of the first electric cylinder (5), so that the position of the laser entering the plasma from one side of the plasma main cavity is adjustable, and the optical fiber (14) is connected and arranged between the optical fiber coupler (15) and the optical fiber through (13) for guiding the laser from the optical fiber through (13) to the optical fiber coupler (15).

6. The optical path of the optical follow-up in the vacuum chamber facing thomson scattering according to claim 1, characterized in that the laser terminator (6) is a cone terminator or a knife stack terminator.

7. The optical path according to claim 1, wherein the laser termination system further comprises a thermometer or a photoelectric sensor (8) and a through flange (10), the thermometer or the photoelectric sensor (8) is arranged on the laser terminator (6), and is electrically connected with an external device through the through flange (10) and used for detecting residual light after laser enters the laser terminator (6) or heating temperature of the laser terminator (6).

8. The thomson scattering oriented vacuum cavity follow-up optical path of claim 7 wherein said laser termination system further comprises a water cooled pipe (9) connected to said laser terminator (6) for cooling said laser terminator (6).

9. The thomson scattering oriented vacuum chamber optical path as claimed in any one of claims 1 to 8, wherein,

the laser light-in light path system and the laser termination system are both arranged in the sealed plasma main cavity;

or,

10. The optical path according to claim 9, wherein the collection lens group (11) comprises two lenses (16) coaxially arranged, and a pinhole (17) is arranged between the two lenses (16) to form a dual-lens pinhole image.