JPH04236474A - Discharge-exciting type laser - Google Patents

Abstract

PURPOSE:To provide a discharge-exciting type laser which can efficiently obtain a laser output and be composed compactly. CONSTITUTION:In a discharge-exciting type laser in which a plurality of discharge units 7 each having a pair of discharge electrodes 5a, 5b disposed oppositely through a discharge space 4 sealed with laser gas 8 and a power source 6 for applying a voltage to the electrodes 5a, 5b, are arranged axially of the space 4 to discharge-excite the gas 8 in each unit 7 to obtain a laser output, the waveforms and the phases of the power source voltages of the respective units 7 are brought in coincidence.

Description

[Detailed description of the invention]

[Purpose of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge-excited laser device, and more particularly to a discharge-excited laser device that can obtain laser output with high efficiency and can be constructed compactly.

0002

2. Description of the Related Art In recent years, laser light oscillated by discharge excitation has been used in a wide range of fields such as medical equipment, metal processing equipment, measuring equipment, and weighing equipment. In particular, laser devices that emit high-output laser beams such as carbon dioxide laser beams are used in processing fields such as cutting, welding, hardening, and surface treatment, and are used to process small parts and brittle materials that were previously difficult to process. It is used in the manufacture of precision machinery and electronic equipment, taking advantage of its ability to process large quantities with high precision in a short period of time.

An example of a discharge-excited laser device used in the various laser processing machines described above is shown in FIG. 5. That is, the discharge excited laser device shown in FIG.
A dielectric 2 attached to the discharge vessel 1, a dielectric 3 disposed within the discharge vessel 1 at a distance from the dielectric 2, and a discharge formed between the dielectric 2 and the dielectric 3. space 4
A pair of electrodes 5a and 5b are provided opposite to each other so as to sandwich the
and a power source 6 that applies a voltage between the electrodes 5a and 5b. Two discharge units 7 are arranged in parallel in the axial direction of the discharge space. Here, as shown in FIG. 5, the two discharge units 7, 7 are distinguished into an A series and a B series for the sake of explanation.

Since the capacity of each discharge unit 7 is limited by the capacity of the power supply 6, especially in a laser device that needs to obtain a high output laser beam, the discharge unit 7 having an individual power supply circuit as described above is used. It is constructed by arranging multiple units in parallel.

When voltages are applied from the power supplies 6 and 6 to the electrodes 5a and 5b of the discharge units 7 and 7 of the A and B series, respectively, a discharge occurs between the dielectrics 2 and 3, and a discharge occurs in the discharge space 4. The enclosed laser gas 8 is excited and a high-power laser beam is emitted. After the emitted laser light is amplified, it is bent by several reflecting mirrors disposed in the optical path, and focused at a predetermined position on the surface of the workpiece by a lens installed in the laser head. Energy is concentrated in a narrow area irradiated with laser light, and is used to form holes in the workpiece, perform cutting, welding, and surface treatment.

[0006]

[Problems to be Solved by the Invention] However, in a discharge-excited laser device configured by arranging a plurality of discharge units each equipped with an individual power supply in parallel as described above, the power supply circuit of each discharge unit is Since the waveforms and phases are different, a potential difference occurs between adjacent electrodes, which often causes abnormal discharge between adjacent electrodes.

That is, since the phases of the output voltages V10 and V20 of the power supplies 6 and 6 of the A series and B series power supply circuits are different from each other as shown in FIG.
The voltages V11 and V21 applied between a and 5b are also different from each other. This means that a potential difference Vd also occurs between electrodes adjacent in the axial direction, and abnormal discharge is likely to occur between the adjacent electrodes.

In order to suppress such abnormal discharge, conventionally, the electrodes 5a, 5b adjacent to each other in the axial direction and the electrodes 5a, 5
It has been necessary to keep an appropriate insulation distance d apart from b. However, since the insulation performance is lower in laser gas than in the atmosphere, in order to more effectively prevent abnormal discharge, it is necessary to set the insulation distance d sufficiently large, which has the disadvantage of increasing the size of the device. there were. On the other hand, the laser gas that stays in the insulating space where no electrodes are placed and no discharge phenomenon occurs has the property of absorbing the oscillated laser light, so this insulating space can reduce the output efficiency of the laser oscillator. there were. In order to compensate for this drawback, it is necessary to equip a power supply with a larger capacity, and in any case, there is a problem that the device configuration becomes excessively large.

The present invention has been made to solve the above problems, and provides a discharge-excited laser device that can obtain laser output with high efficiency and that can be configured compactly. The purpose is to [Structure of the invention]

0010

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a pair of discharge electrodes arranged opposite to each other so as to sandwich a discharge space filled with laser gas, and a power source for applying voltage to the discharge electrodes. In a discharge excitation type laser device that obtains a laser output by arranging a plurality of discharge units in the axial direction of the discharge space and exciting the laser gas by discharge in each discharge unit, the waveform of the power supply voltage of each discharge unit and It is characterized by matching the phases.

[0011]

[Operation] According to the discharge-excited laser device having the above configuration, the waveforms and phases of the power supply voltages of the plurality of discharge units incorporated in the device are configured to match, so that the distance between adjacent electrodes in the axial direction is Since no potential difference is generated between the laser beams and abnormal discharges are less likely to occur, laser oscillation can be performed with high efficiency.

[0012] Furthermore, since the insulation distance can be shortened, the device can be made compact, and the non-excited region of the laser gas can be reduced, thereby providing a discharge-excited laser device that is compact and has high oscillation efficiency. I can do it.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a sectional view showing one embodiment of the present invention, and FIG. 2 is a diagram showing the power supply voltage of the device of this embodiment. Note that the same elements as those in the conventional example shown in FIGS. 5 and 6 are denoted by the same reference numerals, and redundant explanation thereof will be omitted.

That is, the discharge excitation type laser device according to this embodiment includes a pair of discharge electrodes 5a and 5b arranged opposite to each other so as to sandwich a discharge space 4 filled with laser gas 8;
By arranging two discharge units 7 in parallel in the axial direction of the discharge space 4, each consisting of a power source 6 that applies a voltage to the discharge electrodes 5a and 5b, and exciting the laser gas 8 by discharge in each discharge unit 7, A discharge-excited laser device that obtains a laser output includes a phase reference device 8 that matches the waveform and phase of the power supply voltage of each of the discharge units 7, 7.

A-series and B-series discharge units 7, 7
The power supplies 6, 6 are connected to the phase reference device 8, and the power supplies 6, 6 are connected to the phase standard 8.
, 6 each receive a signal from the phase reference device 8 and are adjusted so that their phases and waveforms match. The A series and B series electrodes 5a, 5b and 5 are individually connected to the power supplies 6, 6.
A voltage is applied between a and 5b.

Since the phases and waveforms of the power supplies 6 and 6 of both series match, the output voltage V10 of the power supply 6 of the A series and the power supply 6 of the B series match as shown in FIG. 1.2.
Since the output voltage V20 of the electrodes is almost the same, the voltages applied between the A-series electrodes 5a, 5b and the B-series electrodes 5a, 5b are also equal to each other, and no potential difference occurs, which may cause abnormal discharge. There are also few. Therefore, there is no need to ensure a large insulation distance between electrodes adjacent in the axial direction, and the device can be downsized.

[0017] Furthermore, since the insulation distance can be shortened, it is possible to reduce the non-excited region of the laser gas, and furthermore, the loss due to laser light absorption is reduced, and the laser light oscillation efficiency of the entire device can be greatly increased. . Further, when the oscillation capacity of the laser beam is kept constant, the power supply capacity can be relatively reduced, and the number of power supplies can also be reduced.

Next, regarding other embodiments of the present invention, FIGS.
Explain with reference to. In the embodiment shown in FIG. 3, in addition to the components shown in FIG. It is constructed by disposing phase correctors 9, 9, respectively, to eliminate the phase difference caused by the difference in length.

According to this embodiment, the power supplies 6, 6 are constructed of high-frequency circuits, and a large phase difference occurs between the power supply voltage V10 and the applied voltage V20 of the discharge electrode due to a subtle difference in the length of the power transmission path. Even in this case, the phases of the two can be matched more accurately.

That is, the impedance of the wiring between the power supply 6 and the electrodes 5a and 5b is different for each power supply circuit of the A and B series, and when the voltages on the power supply 6 and 6 sides are matched, the impedance of the wiring between the power supply 6 and the electrodes 5a and 5b is
, 5b, 5a, 5b, even if the phases of the applied voltages differ as shown in FIG.
By adjusting the built-in delay circuit, one power supply voltage V10,
By shifting the phase of V20, the voltages V11 and V2 applied to the discharge electrodes 5a, 5b, 5a, 5b of both series A and B are finally applied.
1 can be adjusted to match each other.

[0021]

Effects of the Invention As explained above, according to the discharge-excited laser device according to the present invention, the waveforms and phases of the power supply voltages of the plurality of discharge units incorporated in the device match, so that the axial There is no potential difference between adjacent electrodes in the direction, and abnormal discharges are less likely to occur.
Laser oscillation can be performed with high efficiency.

[0022] Furthermore, since the insulation distance can be shortened, the device can be made compact, and the non-excited region of the laser gas can be reduced, thereby providing a discharge-excited laser device that is compact and has high oscillation efficiency. I can do it.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an embodiment of a discharge-pumped laser device according to the present invention.

FIG. 2 is a diagram showing the power supply voltage of the device shown in FIG. 1;

FIG. 3 is a sectional view showing another embodiment of the present invention.

FIG. 4 is a diagram showing the power supply voltage and inter-electrode voltage of the device shown in FIG. 3;

FIG. 5 is a cross-sectional view showing a configuration example of a conventional discharge-excited laser device.

6 is a diagram showing the power supply voltage of the laser device shown in FIG. 5. FIG.

[Explanation of symbols]

1 Discharge vessel 2 Dielectric material 3 Dielectric material 4 Discharge space 5a, 5b electrode 6 Power supply 7 Discharge unit 8 Phase reference device 9 Phase corrector

Claims (1)

[Claims] Claim 1: A plurality of discharge units are arranged in the axial direction of the discharge space, each consisting of a pair of discharge electrodes arranged opposite to each other so as to sandwich a discharge space filled with laser gas, and a power supply that applies voltage to the discharge electrodes. A discharge pumped laser device which obtains a laser output by discharging and exciting a laser gas in each discharge unit, characterized in that the waveform and phase of the power supply voltage of each discharge unit are matched. Device.