JPH02143578A - Pulse laser oscillating device - Google Patents

Abstract

PURPOSE:To easily adjust the gap of a pre-ionizing pin in a short time and to make a discharge section compact and a circuit low in inductance so as to obtain a laser oscillator in which a stable discharge takes place by a method wherein a pre-ionizing pin support of a cathode and an anode is formed into an integral structure. CONSTITUTION:Primary electrodes 1 and 2 are arranged facing each other and fixed to potential plates 6 and 7 on a cathode side and an anode side respectively, and the potential plate 6 on a cathode side is fitted to an insulating plate 9. Pre-ionizing pins 4 of the cathode and the anode are fixed to a pre-ionizing pin support 51 formed in an integral structure, furthermore the support 51 is fitted to the potential plate 6 on an anode side, the pre-ionizing pins 4 of the cathode and the anode are independently assembled at the same time before a discharge section is assembled, where a gap G between the pins can be easily adjusted in a short time as the pins 4 are opposed to each other. Moreover, as the pre-ionizing pin support 51 is provided with a connecting section between the cathode and the anode and the connecting section serves as an obstacle for a gas flow, a laser gas is prevented from flowing to a part separate from the primary electrodes 1 and 2, consequently the laser gas can be made to flow effectively through the discharge section.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a pulsed laser oscillation device with an improved mounting structure for a pre-ionization pin of a C02 laser, excimer laser, etc. that operates above atmospheric pressure. .

(Prior Art) Generally, in order to obtain laser oscillation, it is necessary to generate a spatially uniform discharge in a laser medium. However, in pulsed laser oscillators that generate short-pulse laser beams such as TEA/TEMA-Co□ lasers and excimer lasers that operate above atmospheric pressure, the laser gas in the discharge section must be sufficiently pre-ionized to obtain a stable discharge. If the main discharge is not turned on after this, the main discharge will become uneven and arcing will occur.

Preliminary ionization sources include UV (ultraviolet light), corona, and X-rays, but in the present pulsed laser oscillation device, UV light generated by spark gap discharge is generally used as a preliminary ionization source.

The structure of a conventional discharge electrode section is shown in FIG. Main electrodes 1, 2
are arranged facing each other about the center of the optical axis and are fixed to potential plates 6 and 7 on the cathode and anode sides, respectively, and the cathode side electrode plate 6 is attached to an insulating plate 9.

On the other hand, in order to cause a uniform and stable glow discharge between the main heavy poles 1 and 2, it is necessary to pre-ionize the laser gas between the main electrodes 1 and 2.
They are attached to a pre-ionization pin support 5 fixed to the potential plates 6 and 7 on the anode side and are arranged opposite to each other. Furthermore, the preliminary electrode pins 4 on each negative and anode side are electrically connected to the peaking capacitor 3 to which potential plates 6 and 7 are attached. The potential plate 7 on the anode side is attached to the cathode side with a return conductor 8 that also serves as a support between the cathode and the anode.

The part of the return conductor 8 facing the main electrode discharge part is the opening 1.
2 is provided through which the laser gas flows. On the other hand, the voltage applied from the excitation circuit 10 flows through the paths of potential plate 6 - peaking capacitor 3 - preionization pin 4 and return conductor 8 - potential plate 7 - peaking capacitor 3 - preionization pin 4, A discharge occurs in the gap G between the tips of the pre-ionization pins 4, and the main discharge portion is irradiated with ultraviolet rays by this discharge. Therefore, if the pre-ionization pin gap G varies between each pin or varies in the X and Y directions between the upper and lower pre-ionization pins 4, the timing of starting discharge between the gaps 6 and the strength of the pre-ionization Since the pre-ionization pins 4 differ in each other, the main discharge becomes uneven, and the laser output fluctuates greatly, making it impossible to obtain a stable high-output laser.

(Problem M to be solved by the invention) In the structure shown in Fig. 4, each preliminary ionization pin 4 on the cathode and anode side
is attached to a pre-ionization pin support 5 fixed to each electrode-side potential plate, so each electrode is assembled separately and then both are assembled. When assembling each electrode individually, the mounting dimensions of the pre-ionization pin 4 must be carefully considered, but at this time, since there is no mating pre-ionization pin 4, there is a limit to the accuracy of the assembly dimensions. For this reason, after combining the cathode and anode sides, readjustment is performed while measuring the actual pin spacing. That is, the insulating plate 9 on the cathode side
The potential plate 7 on the anode side is fixed with a support plate (not shown) in the optical axis direction, and adjustment is performed without the return conductor 8, but since the space is small, the workability is poor and it takes a lot of time.

In order to obtain a stable discharge with a pulsed laser, it is also necessary to reduce the inductance of the circuit and apply a voltage that rises quickly to the main discharge section. One of the factors to reduce inductance is to reduce the dimension between the main electrode and the return conductor as much as possible. The gap L between the return conductor 8 on the cathode side potential plate 6 is the same as the voltage applied between the main electrodes, and an insulation distance sufficient to withstand this is inevitably required, so that the size between the main electrode 1 and the return conductor 8 can be reduced. It is necessary to reduce the potential width on the cathode side.

The purpose of the present invention is to improve the workability of adjusting the pre-ionization pin.
It is an object of the present invention to provide a laser oscillation device that shortens assembly time and improves the accuracy of the mounting method, and also makes the discharge section compact and reduces the inductance of the circuit, thereby providing stable discharge.

[Structure of the invention]

(Means for Solving the Problems) The pulsed laser oscillation device of the present invention has a cathode-integrated pin support to which a pre-ionization pin for pre-ionizing the laser gas in the main discharge section is attached, and this is fixed at the main electrode attachment potential on one side. It is characterized by being attached to the board, and furthermore, the peaking capacitor on the electrode side opposite to the side where the pin support is attached is moved closer to the main electrode by utilizing the space where the pin support is removed. That is.

(Function) In the present invention, by integrating the cathode and anode preionization pin supports, the preionization bin gap can be adjusted easily in a short time, and the cathode side peaking capacitor The discharge electrode section can be made more compact by the size equivalent to the distance closer to the main electrode side, and the inductance can be lowered.

(Example) The present invention will be described below with reference to an example shown in FIGS. 1 and 2. The main electrodes 1.2 are arranged opposite to each other and are fixed to potential plates 6, 7 on the cathode and anode sides, respectively, and the potential plate 6 on the cathode side is attached to an insulating plate 9.

The cathode-anode pre-ionization pin 4 is attached to a pre-ionization pin support 51 made of one piece, and the pre-ionization pin support 51 is attached to the potential plate 7 on the anode side. There is an opening on the opposite side for flowing the laser gas, and the width of the opening is wider than the length of the main electrode. Each pre-ionization pin is connected to a peaking capacitor 3 attached to each electrode potential plate 6, 7 via a connecting conductor.

Further, the cathode side and anode side are fixed and fixed by a return conductor 9 that also serves as a current return path on the anode side and a support plate (not shown) in the optical axis direction.
installed.

According to the present invention, the cathode/anode pre-ionization pin 4 is attached to the integrated pin support 51, so that the cathode/anode pre-ionization pin 4 can be assembled independently and at the same time before assembling the discharge section. Since there are opposing pins, the distance G between each pin can be easily adjusted in a short time. Also, the projecting dimensions in the X direction of each pre-ionization pin 4 and the anode/anode pins 11, 0. The dimensions (Fig. 2) can also be adjusted with high precision. Furthermore, since the pre-ionization pin support 51 is fixed to one electrode potential plate, it is not affected by the dimensional accuracy and mounting dimensions of the other electrode. The connection between the peaking capacitor 3 on the cathode side and the pre-ionization pin 4 can be made by attaching the connection conductor 11 to the pre-ionization pin 4 in advance, so that even after combining both electrodes, the connection between the connection conductor 11 and the peaking capacitor 3 can be made. It can be easily installed even in narrow spaces by simply tightening the screws. On the other hand, since the opening width υ2 of the pre-ionization pin support 51 is longer than the main pole length W, the laser gas flow in the main discharge section is hardly affected by the support. Since there is a connection between the cathode and anode, this becomes an obstruction to the gas flow and prevents the laser gas from flowing away from the main electrode, allowing the laser gas to flow effectively into the discharge section.

Another embodiment will be described with reference to FIG.

In the configuration of the embodiment shown in FIG. 1, the cathode side peaking capacitor 3 is moved closer to the main electrode side by utilizing the space without the pre-ionization pin support, and the potential plate is moved by the distance closer to the main electrode side. The zero dimension is made smaller, and the potential plate on the cathode side is also made smaller. Since the anode side does not require an insulation distance corresponding to five dimensions on the cathode side, there is no problem with this.

As a result, the dimension between the main electrode and the return conductor is reduced, the circuit inductance can be reduced accordingly, and a voltage with a faster rise can be applied to the discharge section, contributing to stable discharge. It goes without saying that the smaller the dimensions, the more compact the discharge section will be.

〔Effect of the invention〕

As described above, according to the present invention, the gap between the preionization pins is improved by simply making the preionization pin support with an anode/cathode integrated structure, and by arranging the peaking capacitor in the empty space. Dimensional adjustments can be easily made in a short time, the inductance of the discharge circuit can be reduced, and a voltage with a faster rise can be applied to the main electrode, allowing stable discharge and stable laser output. Furthermore, the discharge section can also be made compact, making it possible to provide a compact pulsed laser oscillation device.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the discharge section of the pulsed laser oscillation device of the present invention, and FIG. 2 is a plane view of the pre-ionization pin support as viewed from the main electrode side in the gas flow direction in FIG. 3 are sectional views of other embodiments, and FIG. 4 is a plan view of a discharge portion of a conventional laser oscillation device. 1.2 Main electrode 3 Peaking capacitor 4 Pre-ionization pin 5.51 Pre-ionization pin support 6.7 Potential plate 8 Return conductor 9・・・
Insulation board agent Patent attorney Nori Chika Ken Yudo Daishimaru Kendaizu

Claims (1)

[Claims] A pulsed laser oscillation device having a discharge section consisting of a set of main electrodes, a potential plate that fixes the main electrode, a peaking capacitor attached to the potential plate, a pin support for ultraviolet ionization, and a pin for pre-ionization attached to the pin support. In this method, the pre-ionization supports on the cathode and anode side are made from a single piece of both electrodes, and the ionization pin support is attached to one of the potential plates, and the pre-ionization pin support has a laser gas flow opening that is at least longer than the length of the main electrode. A pulsed laser oscillation device characterized by: