Gas laser electrode and gas laser

Abstract

This application relates to the field of laser technology, and discloses a gas laser electrode and a gas laser using the electrode. Among them, the gas laser electrode includes an anode and a cathode arranged oppositely; a discharge surface is provided on the surface of the anode and / or the cathode, and a shock wave suppression surface is provided on one side or both sides of the discharge surface, and a plurality of grooves are provided on the shock wave suppression surface, and the grooves are used to scatter the shock wave. The gas laser electrode of this application has a surface structure in its non-discharge area that can break up the shock wave and prevent the reflection of the shock wave, so that on the basis of stable glow discharge, the electrode can effectively suppress the reflected shock wave between the electrodes and reduce its impact on the discharge and light output performance.

Description

Technical Field

[0001] This application relates to the field of laser technology, and particularly to an electrode for a gas laser and a gas laser using such an electrode. Background Art

[0002] In a pulsed gas laser pumped by discharge, especially in a high-repetition-rate excimer laser, there exists a perturbation similar to a micro-explosion, namely the discharge shock wave phenomenon. This is because when the high-voltage pulsed power supply of the gas laser pumps the discharge medium gas, it injects 2 - 4 J of energy into it within about 100 ns. Research has found that a considerable part of the energy is instantaneously deposited on the surfaces of the cathode and anode, and its rapid expansion will generate a cylindrical shock wave originating from the electrode surface. The cathode and anode shock waves reflect back and forth between the electrode and its attached structures until it basically subsides at 200 μs. Such repeatedly reflected shock waves will cause local gas density oscillations wherever they reach, thereby affecting the quality of the discharge and the propagation of the light beam, and ultimately affecting the energy stability, line width, and beam quality of the laser.

[0003] To reduce the impact of the shock wave on the laser, it is necessary to suppress it. The suppression method adopted in the prior art is to install sound-absorbing materials on both sides of the electrode to absorb the shock wave energy. The sound-absorbing materials are usually high-purity alumina ceramics, which have a high cost and are difficult to prepare and process. Summary of the Invention

[0004] The purpose of this application is to provide an electrode for a gas laser and a gas laser using such an electrode, aiming to solve the technical problems of high cost and large processing difficulty in suppressing shock wave energy in the prior art.

[0005] An embodiment of this application provides an electrode for a gas laser, including an anode and a cathode arranged oppositely; a discharge surface is provided on the surface of the anode and / or the cathode, and a shock wave suppression surface is provided on one side or both sides of the discharge surface. A plurality of grooves are provided on the shock wave suppression surface, and the grooves are used to scatter the shock wave.

[0006] Further, the included angle between the discharge surface and the shock wave suppression surface is 20 - 30°.

[0007] A smooth transition surface is further included in the embodiment of this application, and the transition surface is provided between the discharge surface and the shock wave suppression surface.

[0008] Further, the width of the transition surface is 1 - 2 times the width of the discharge surface.

[0009] Further, the included angle between the discharge surface and the transition surface is 20 - 30°.

[0010] Further, both the anode and the cathode are strip electrodes; the extending directions of the plurality of grooves are the same as or perpendicular to the extending direction of the strip electrodes.

[0011] Further, the plurality of grooves are parallel or non - parallel to each other.

[0012] Further, the depth of each groove is any value between 0.5 mm and 3 mm, and the width of each groove is any value between 0.1 mm and 1 mm.

[0013] Further, the shape of the groove is one or more of a rectangular groove, a wedge - shaped groove, a dovetail groove, and a T - shaped groove; when the groove is a wedge - shaped groove, the bottom angle of the cross - section of the wedge - shaped groove is an acute angle or an obtuse angle.

[0014] The embodiment of the present application also provides a gas laser, and the electrodes used in the gas laser are the gas laser electrodes disclosed in the above - mentioned embodiment.

[0015] Based on the above technical solution, compared with the prior art, the gas laser electrode proposed in the embodiment of the present application has the function of suppressing shock waves by itself, and the suppression efficiency is better than that of the prior art. The reason is that the electrode is the source of shock wave generation. Its surface encounters the shock wave earlier than other places, and the intensity of the encountered shock wave is also the strongest. Weakening the shock wave here will undoubtedly have the highest suppression efficiency. The gas laser electrode of the present application has a surface structure in its non - discharge area that can disperse shock waves and prevent shock wave reflection, enabling the electrode to effectively suppress the reflected shock waves between the electrodes on the basis of stable glow discharge, and reducing its impact on the discharge and light - emitting performance. At the same time, the electrode structure of the present application is simple and can be manufactured by conventional mechanical processing, without the need to produce complex and expensive intracavity sound - absorbing materials as in the prior art, thus reducing the cavity cost. Description of the Drawings

[0016] Figure 1 It is a schematic structural diagram of the gas laser electrode in the first embodiment of the present application;

[0017] Figure 2 It is a schematic structural diagram of the cathode in the gas laser electrode in the second embodiment of the present application;

[0018] Figure 3 It is a schematic structural diagram of the cathode in the gas laser electrode in the third embodiment of the present application;

[0019] Figure 4 It is a schematic structural diagram of the cathode in the gas laser electrode in the fourth embodiment of the present application;

[0020] Figure 5This is a schematic diagram of the structure of the cathode in the gas laser electrode in the fifth embodiment of the present application.

[0021] In the figure, 201 is the cathode; 202 is the anode; 203 is the discharge surface; 204 is the shock wave suppression surface; 204-1 is the groove; 205 is the transition surface. Detailed implementation manners

[0022] In order to make the objectives, technical solutions and advantages of the present application more clear and understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0023] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intermediate element at the same time.

[0024] In addition, it should also be noted that the azimuth terms such as left, right, up, and down in the embodiments of the present application are only relative concepts to each other or are referenced based on the normal use state of the product, and should not be considered as restrictive. The implementation of the present application will be described in detail below with reference to specific embodiments.

[0025] As Figures 1 to 5 shown, an embodiment of the present application provides a gas laser electrode, including an anode and a cathode disposed opposite to each other; a discharge surface is provided on the surface of the anode and / or the cathode, and a shock wave suppression surface is provided on one side or both sides of the discharge surface. A plurality of grooves are provided on the shock wave suppression surface, and the grooves are used to scatter the shock wave to achieve the purpose of suppressing the shock wave.

[0026] In order to avoid the occurrence of bypass discharge, the embodiment of the present application sets the angle between the discharge surface and the shock wave suppression surface to any value between 20° and 30°.

[0027] To ensure that the discharge only occurs on the discharge surface, the embodiment of the present application also includes a smooth transition surface, which is disposed between the discharge surface and the shock wave suppression surface. Further, the width of the transition surface is 1 to 2 times the width of the discharge surface, and the angle between the discharge surface and the transition surface is 20 to 30°.

[0028] The present application also discloses a gas laser using the above electrode.

[0029] Embodiment 1:

[0030] Figure 1 This is a schematic diagram of the structure of an embodiment of the present application.

[0031] The cathode 201 and the anode 202 are oppositely arranged and are both strip electrodes, and the material is one of metal materials such as brass, aluminum, nickel, etc. The cross-sectional shape of the strip electrode is a structure combined by a trapezoid and a rectangle, and the long side of the rectangle is attached to the lower bottom surface of the trapezoid. The cathode 201 is supplied with high voltage by a high-voltage pulse power supply; the anode 202 is grounded. On the surfaces of the cathode 201 and the anode 202, there are a discharge surface 203, a shock wave suppression surface 204 and a transition surface 205. Among them, the discharge surface 203 is the upper bottom surface of the trapezoid, and the shock wave suppression surface 204 and the transition surface 205 are located on the waists of the trapezoid. The discharge surface 203 is a glow discharge area, and the included angle between the discharge surface 203 and the shock wave suppression surface 204 is between 20° and 30°. The test results show that too small an angle between the discharge surface and the shock wave suppression surface is likely to cause bypass discharge, making the actual discharge width wider; while too large an angle will reduce the area of the shock wave suppression surface, thereby reducing the shock wave weakening effect.

[0032] The width of the transition surface 205 is preferably 1-2 times the width of the discharge surface 203. Too small a width of the transition surface will affect the removal of discharge residual products by the flow field, thereby generating abnormal discharge; while too large a width of the transition surface will make the shock wave suppression surface far from the discharge area and reduce the shock wave suppression efficiency.

[0033] In this embodiment, a plurality of grooves 204-1 extending along the extending direction of the strip electrode are formed on the shock wave suppression surface 204, and the grooves 204-1 are rectangular grooves. The depth of the rectangular groove is 0.5 mm, and the width of each rectangular groove is 0.1 mm. There is a transition surface 205 between the discharge surface and the shock wave suppression surface, and the function of the transition surface 205 is to ensure that discharge does not occur on the shock wave suppression surface. The included angle between the transition surface 205 and the discharge surface 203 is between 20° and 30°. The test results show that too small an angle is likely to cause bypass discharge, making the actual discharge width wider; while too large an angle will reduce the area of the shock wave suppression surface, thereby reducing the shock wave weakening effect.

[0034] In the embodiment of the present application, the shock wave suppression surface 204 on the cathode 201 and / or the anode 202 can adopt various structures. Hereinafter, the shock wave suppression surface 204 on the cathode 201 in Embodiment 1 will be described in detail. See Figures 2 to 5 .

[0035] Embodiment 2:

[0036] As Figure 2 shown, in this embodiment, a plurality of grooves 204-1 are formed on the shock wave suppression surface 204 provided on the cathode 201. The grooves 204-1 are rectangular grooves, the extending direction of the rectangular grooves is the same as the extending direction of the cathode 201, the plurality of rectangular grooves are parallel to each other, the depth of the rectangular groove is 1 mm, and the width of each rectangular groove is 0.5 mm.

[0037] Example 3:

[0038] As Figure 3 shown, in this embodiment, a plurality of grooves 204-1 are formed on the shock wave suppression surface 204 provided on the cathode 201. The grooves 204-1 are rectangular grooves, and the extending direction of the rectangular grooves is the same as the extending direction of the cathode 201. The plurality of rectangular grooves are not parallel to each other. The depth of the rectangular grooves is 3 mm, and the width of each rectangular groove is 1 mm.

[0039] Example 4:

[0040] As Figure 4 shown, in this embodiment, a plurality of grooves 204-1 are formed on the shock wave suppression surface 204 provided on the cathode 201. The grooves 204-1 are rectangular grooves, and the extending direction of the rectangular grooves is perpendicular to the extending direction of the cathode 201. The plurality of rectangular grooves are parallel to each other. The depth of the rectangular grooves is 2 mm, and the width of each rectangular groove is 0.8 mm.

[0041] Example 5:

[0042] As Figure 5 shown, in this embodiment, a plurality of grooves 204-1 are formed on the shock wave suppression surface 204 provided on the cathode 201. The grooves 204-1 are wedge-shaped grooves, and the wedge-shaped grooves adopt irregular wedge tips. The extending direction of the wedge-shaped grooves is the same as the extending direction of the cathode 201. The plurality of wedge-shaped grooves are parallel to each other. The depth of the wedge-shaped grooves is 1.5 mm, and the bottom angle of the cross-section of the wedge-shaped grooves is an acute angle or an obtuse angle and cannot be a right angle. Because when the angle is a right angle, the shock wave will be returned along the original direction.

[0043] The plurality of grooves in this application can also be set to have different extending directions, such as being arranged vertically and horizontally in a staggered manner.

[0044] Preferably, the anode and the cathode in the above embodiments of this application are strip electrodes; at this time, the extending direction of the plurality of grooves is the same as or perpendicular to the extending direction of the strip electrodes. Among them, the plurality of grooves are parallel or not parallel to each other; the depth of each groove is any value between 0.5 mm and 3 mm, and the width of each groove is any value between 0.1 mm and 1 mm; the shape of the groove is one or more of a rectangular groove, a wedge-shaped groove, a dovetail groove, and a T-shaped groove. When it is a wedge-shaped groove, the bottom angle of the cross-section of the wedge-shaped groove is an acute angle or an obtuse angle and cannot be a right angle. When the angle is a right angle, the shock wave will be returned along the original direction.

[0045] Preferably, the depth of the groove can be set to be deeper closer to the discharge area; in this way, the absorption effect on the shock wave is better.

[0046] Preferably, when the depths or widths of the grooves are the same, it is convenient for processing.

[0047] The above-described embodiments are only specific implementation manners of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily think of various equivalent modifications, substitutions, improvements, etc., and these modifications, substitutions, and improvements should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A gas laser electrode, characterized in that, it includes an anode and a cathode arranged oppositely; on the surface of the anode and / or the cathode, there are a discharge surface and a shock wave suppression surface integrated with the anode and / or the cathode on one side or both sides of the discharge surface. A plurality of grooves are arranged on the shock wave suppression surface, and the grooves are used to scatter shock waves. A transition surface is also arranged between the discharge surface and the shock wave suppression surface; wherein: the included angle between the discharge surface and the shock wave suppression surface is 20 - 30°, the width of the transition surface is 1 - 2 times the width of the discharge surface, and the included angle between the discharge surface and the transition surface is 20 - 30°.

2. The gas laser electrode according to claim 1, characterized in that, both the anode and the cathode are strip electrodes; the extending directions of the plurality of grooves are the same as or perpendicular to the extending direction of the strip electrodes.

3. The gas laser electrode according to claim 2, characterized in that, the plurality of grooves are parallel or non - parallel to each other.

4. The gas laser electrode according to any one of claims 1 - 3, characterized in that, the depth of each groove is any value between 0.5 mm and 3 mm, and the width of each groove is any value between 0.1 mm and 1 mm.

5. The gas laser electrode according to any one of claims 1 - 3, characterized in that, the shape of the groove is one or more of a rectangular groove, a wedge - shaped groove, a dovetail groove, and a T - shaped groove. When the groove is a wedge - shaped groove, the bottom angle of the cross - section of the wedge - shaped groove is an acute angle or an obtuse angle.

6. A gas laser, characterized in that, it includes the gas laser electrode according to any one of claims 1 - 5.

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