JPH10313140A - Laser oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser oscillator, which is not also an obstacle to the flow of laser gas after an inductance is made small and can take place a high repetition oscillation in a large output. SOLUTION: Return members 5 for forming paths for making a current subsequent to a discharge in a discharge part of a laser oscillator flow to ground are respectively constituted of a plurality of tabular members, and at the same time, the members 5 are arranged in such a way as to run parallel to the longitudinal directions of main electrodes 4 (4a and 4b). Moreover, the tabular surfaces, which are positioned in the center part of the gas flow path of laser gas, of the members 5 are turned in a direction of 90 deg. with respect to the gas flow path.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser oscillator for converting input power into a very narrow and powerful coherent laser beam.

[0002]

2. Description of the Related Art A laser oscillator is used as a processing heat source for processing, reforming, and the like. In particular, the oscillation efficiency is increased by lowering the inductance of a discharge circuit to obtain a large output.

FIG. 9 shows that no repetitive oscillation occurs or one
FIG. 3 is an explanatory diagram of a laser oscillator that performs repetitive oscillation of about pps or less. The high voltage from the power supply is input to the high-voltage introduction plate 1, and the electric charge supplied to the high-voltage introduction plate 1 from the power supply is stored in the peaking capacitor 2 while flowing between the preliminary ionization pins 3 a and 3 b. Preliminary ionization discharge occurs. Next, the electric charge of the peaking capacitor 2 is
a main discharge between the main member 4a and the main electrode 4b.
Through to ground.

In such a low repetition rate laser oscillator, it is necessary to reduce the inductance of the discharge circuit in order to increase the oscillation efficiency. Therefore, a return member 5 is provided to return the discharged current to the ground potential. The return member 5 is generally mounted as a metal plate in parallel with the longitudinal direction of the main electrode 4.

On the other hand, in a laser oscillator that performs high repetition oscillation, it is necessary to discharge the contaminated laser gas after oscillation before the next oscillation. FIG. 10 is an explanatory diagram of a high repetition rate laser oscillator. As shown in FIG. 10, in such a high-repetition-rate laser oscillator, the next oscillation cannot be performed unless the contaminated laser gas after oscillation is forced to flow, so that the return member is required to secure a gas flow path. Reference numeral 5 is disposed at the end in the optical axis direction so as not to hinder the flow of the laser gas. That is, the laser gas is caused to flow in a direction perpendicular to the longitudinal direction (optical axis direction) of the main electrode 5 to improve the oscillation efficiency. Therefore, the length of the discharge circuit including the return member 5 becomes longer.

When the return member 5 is arranged at the same position as the laser oscillator shown in FIG. 9 in order to reduce the length, a plurality of cylindrical thin rods are used as the return member 5 as shown in FIG. I often passed through.

[0007]

However, in the conventional low repetition rate laser oscillator, if the return member 5 is provided on the side surface in the longitudinal direction in order to reduce the inductance of the discharge circuit, the repetition of laser oscillation cannot be increased. Further, when the return member is arranged on the side surface in the optical axis direction so as not to hinder the laser gas flow for the repetitive oscillation, the distance over which the charge flows becomes longer and the inductance becomes larger.

In addition, in the case of high-frequency oscillation, electric charges flow near the surface of the substance. Therefore, even if the columnar return member is arranged in the longitudinal direction to shorten the distance, the surface area of the portion through which current flows becomes narrow. For this reason, the inductance also increases, and the oscillation efficiency decreases.

SUMMARY OF THE INVENTION An object of the present invention is to provide a laser oscillator which has a small inductance and does not hinder the flow of a laser gas, and is capable of high power and high repetition oscillation.

[0010]

According to a first aspect of the present invention, there is provided a laser oscillator comprising a plurality of plate-like return members which form a path through which a current after discharge in a discharge unit of the laser oscillator flows to the ground. It is composed of a member and arranged so as to be parallel to the longitudinal direction of the main electrode. The plate surface of the return member at the center of the gas flow path of the laser gas is oriented at 90 ° to the gas flow path.

The laser oscillator according to the second aspect of the present invention comprises:
In the first aspect of the present invention, the return member is formed by twisting in the same direction at both ends of the gas flow path to form a plate surface in a direction of 90 ° with respect to the gas flow path.

A laser oscillator according to a third aspect of the present invention comprises:
In the first aspect of the present invention, the return member is formed by twisting in opposite directions at both ends of the gas flow path to form a plate surface in a direction of 90 ° with respect to the gas flow path.

A laser oscillator according to a fourth aspect of the present invention comprises:
In the invention of claim 1, the return member is formed by twisting at one end of the gas flow path to form a plate surface in a direction of 90 ° with respect to the gas flow path.

A laser oscillator according to a fifth aspect of the present invention comprises:
According to the first aspect of the present invention, the return member forms a plate surface in a direction of 90 ° with respect to the gas flow path by crushing the plate member.

A laser oscillator according to a sixth aspect of the present invention comprises:
According to the first aspect of the present invention, the return member has a shape in which a plate surface in a direction of 90 ° with respect to the gas flow path is wavy.

A laser oscillator according to a seventh aspect of the present invention comprises:
According to the first aspect of the present invention, the return member has a mounting surface portion perpendicular to the plate surface in a direction of 90 ° with respect to the gas flow path at both ends.

The laser oscillator according to the invention of claim 8 is:
According to the first aspect of the present invention, the return member is formed such that its plate surface is angled in a direction in which the laser gas is to be collected.

According to a ninth aspect of the present invention, there is provided a laser oscillator comprising:
In the first aspect of the present invention, the return members are arranged at different intervals so that the laser gas becomes uniform in the optical axis direction of the laser light.

[0019]

Embodiments of the present invention will be described below. FIG. 1 is a configuration diagram of a laser oscillator according to a first embodiment of the present invention. In FIG. 1, the electric charge supplied from the power supply to the high-voltage introduction plate 1 causes a preliminary ionization discharge between the preliminary ionization pins 3a and 3b while being stored in the peaking capacitor 2. Next, the electric charge of the peaking capacitor 2 performs a main discharge between the main electrode 4a and the main electrode 4b and flows to the ground through the return member 5.

The return member 5 is composed of a plurality of plate-like members, and the plate surface of the return member 5 at the center of the gas flow path of the laser gas is formed to be oriented at 90 ° to the gas flow path. .

FIG. 2 is an explanatory view of the first embodiment of the return member 5. As shown in FIG. As shown in FIG. 2, the return member 5
It is formed by twisting a belt-like plate at two places in the middle. In other words, both ends of the gas flow path are twisted in the same direction to form a plate surface in a 90 ° direction with respect to the gas flow path. Thus, the area of the portion corresponding to the gas flow path is minimized while securing the cross-sectional area where the discharge current flows. Therefore, the flow of the laser gas is not hindered. Further, since the return member 5 is twisted twice in the same direction, the flow of the laser gas can be made directional.

FIG. 3 is an explanatory view of a second embodiment of the return member 5. As shown in FIG. As shown in FIG. 3, the return member 5
It is formed by twisting a belt-like plate at two places in the middle. That is, the gas flow path is twisted in opposite directions at both ends to form a plate surface in a 90 ° direction with respect to the gas flow path.

As described above, since the plate surface of the return member 5 is shifted in the opposite direction by 90 ° at both ends of the portion corresponding to the flow path of the laser gas, the laser gas flow can be guided from the wide frontage to the narrow frontage. Can be guided from a wide place to a narrow place (between the main electrodes).

In the above description, the plate-like return member 5 is
Although twisting is performed at the point, it is also possible to twist at one end of the gas flow path to form a plate surface in a direction of 90 ° with respect to the gas flow path. In this case, the method of attaching the return member 5 is changed.

FIG. 4 is an explanatory view of a third embodiment of the return member 5. As shown in FIG. 4, the return member 5
By crushing the plate member, a plate surface in a direction of 90 ° with respect to the gas flow path is formed. As described above, since the plate-shaped member is not twisted and a 90 ° twisted plate surface is created by crushing, the same cross-sectional area as when twisted can be secured, and since there is no twist, the return without changing the laser gas flow is performed. The flow can be performed in the same state as the front surface of the member 5.

FIG. 5 is an explanatory view of a fourth embodiment of the return member 5. As shown in FIG. 5, the return member 5
The plate is formed in a wavy shape in the direction of 90 ° with respect to the gas flow path. In this manner, the laser surface flowing between the main electrodes 4 is made more uniform in the discharge direction by waving the plate surface between the two twists (or crushes). That is, in the return member 5 in the fourth embodiment, there is no shadow of the laser gas flow in the direction parallel to the axis connecting the main electrode 4a and the main electrode 4b. The flowing laser gas becomes more uniform in the discharge direction.

FIG. 6 is an explanatory view of a fifth embodiment of the return member 5. 6A is a front view, FIG. 6B is a plan view, and FIG. 6C is a side view. As shown in FIG. 6, at both ends of the return member 5, mounting surface portions 6a and 6b perpendicular to the plate surface in a direction of 90 ° with respect to the gas flow path are provided. That is, the return member 5 has two mounting surfaces 6a and 6b, which are plates perpendicular to each other, attached to both ends. The mounting surface 6 allows the return member 5 to be mounted on the discharge circuit.

As described above, in the fifth embodiment, since the return member 5 through which the laser gas flow easily flows is formed only by bending at both ends, its manufacture is simple. That is, 1
It can be easily made simply by bending both ends of the return members 5 so as to be perpendicular to each other.

Next, a second embodiment of the present invention will be described. FIG. 7 is an explanatory view showing the arrangement of the return member 5 of the laser oscillator according to the second embodiment of the present invention. In the second embodiment, the plate surface of the return member is angled toward the direction in which the laser gas is to be collected. That is, the intermediate portion of the two twists of the return member 5 is arranged at an angle to the direction perpendicular to the optical axis direction. By arranging the plate surface of the return member 5 so as to be inclined with respect to the optical axis direction, the return gas can be directed in a direction in which the laser gas is to be collected.

Next, a third embodiment of the present invention will be described. FIG. 8 is an explanatory view showing the arrangement of the return member 5 of the laser oscillator according to the third embodiment of the present invention. In the third embodiment, the return members 5 are arranged at different intervals so that the laser gas becomes uniform in the optical axis direction of the laser light. That is, the arrangement pitch of the return members 5 is appropriately changed so that the electric or laser gas can flow more uniformly in the optical axis direction. As described above, by appropriately changing the arrangement pitch of the return members 5 so that electricity or laser gas can flow more uniformly in the optical axis direction, large-output oscillation with increased efficiency can be achieved.

[0031]

As described above, according to the present invention,
Since the plate-like return member is configured to change the direction of the plane in the middle of the discharge portion of the laser oscillator, the inductance of the discharge circuit can be suppressed low. In addition, laser light with high repetition and high output can be obtained without obstructing the flow of the laser gas.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a laser oscillator according to a first embodiment of the present invention.

FIG. 2 is an explanatory view of a first example of a return member according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram of a second example of the return member according to the first embodiment of the present invention.

FIG. 4 is an explanatory view of a third example of the return member according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram of a fourth example of the return member according to the first embodiment of the present invention.

FIG. 6 is an explanatory view of a fifth example of the return member according to the first embodiment of the present invention.

FIG. 7 is an explanatory diagram showing an arrangement of a return member of a laser oscillator according to a second embodiment of the present invention.

FIG. 8 is an explanatory diagram showing an arrangement of a return member of a laser oscillator according to a third embodiment of the present invention.

FIG. 9 is an explanatory diagram of a conventional low repetition rate laser oscillator.

FIG. 10 is an explanatory view of a conventional high repetition rate laser oscillator having a return member attached in the optical axis direction.

FIG. 11 is an explanatory view of a conventional high repetition rate laser oscillator in which a return member is attached in parallel with a longitudinal direction of a main electrode.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 High-voltage introduction board 2 Peaking capacitor 3 Pre-ionization pin 4 Main electrode 5 Return member 6 Mounting surface

Claims (9)

[Claims] 1. A laser oscillator according to claim 1, wherein a return member for forming a path for a current after discharging in a discharge portion of the laser oscillator to flow to the ground is arranged parallel to a longitudinal direction of the main electrode. Is constituted by a plurality of plate members, and a plate surface of the return member at a central portion of a gas flow path of the laser gas is oriented in a direction of 90 ° with respect to the gas flow path. 2. The laser according to claim 1, wherein the return member is twisted in the same direction at both ends of the gas flow path to form a plate surface in a direction of 90 ° with respect to the gas flow path. Oscillator. 3. The laser according to claim 1, wherein the return member is twisted in opposite directions at both ends of the gas flow path to form a plate surface in a direction of 90 ° with respect to the gas flow path. Oscillator. 4. The return member twists at one end of the gas flow path and has a 90
2. The laser oscillator according to claim 1, wherein a plate surface in the direction of ゜ is formed. 5. The laser oscillator according to claim 1, wherein the return member forms a plate surface in a direction of 90 ° with respect to the gas flow path by crushing the plate member. 6. The laser oscillator according to claim 1, wherein the return member has a shape in which a plate surface in a direction of 90 ° with respect to the gas flow path is wavy. 7. The laser oscillator according to claim 1, wherein the return member has, at both ends thereof, mounting surfaces perpendicular to a plate surface in a direction of 90 ° with respect to the gas flow path. 8. The laser oscillator according to claim 1, wherein the return member is formed so that its plate surface is angled toward a direction in which the laser gas is to be collected. 9. The laser oscillator according to claim 1, wherein the return members are arranged at different intervals so that the laser gas becomes uniform in the optical axis direction of the laser light.