JPH05251802A - Gas laser oscillator - Google Patents

Abstract

(57) [Summary] [Purpose] To enable stable generation of a laser beam without increasing the discharge air velocity and air volume of the blower. [Configuration] Gas laser main body 21 in which laser gas is enclosed
And a blower 23 that circulates the laser gas in the gas laser body 21, a cooler 22 that cools the circulated laser gas, and a pair of discharge electrodes 26a and 26b provided in the circulation path of the laser gas. In this case, by providing the insulating plates 28a, 28b having an arc-shaped cross section, which are located in the circulation path of the laser gas and cover the discharge electrodes 26a, 26b, respectively, the distance of the flat portion of the discharge part is shortened. The generation of the velocity boundary layer was suppressed thin, and the inflow speed and outflow speed of the laser gas were slowed down to suppress the pressure loss.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas laser oscillator which is excited by gas discharge, and more particularly to a gas laser oscillator having an improved discharge part.

[0002]

2. Description of the Related Art Conventionally, a gas laser oscillating device of this kind having a structure as shown in FIG. 4 has been provided.

In FIG. 4, reference numeral 1 denotes a gas laser main body. Inside the gas laser main body 1, a pair of substrates 2a and 2b are provided in parallel in the upper and lower directions. The substrates 2a and 2b have a flat plate-shaped discharge electrode 3 on their opposite surfaces.
a, 3b and insulating plates 4a, 4b of the same plate shape sandwiching the discharge electrodes 3a, 3b from both sides are attached. The discharge electrodes 3a and 3b are connected to a high voltage power source (not shown).

Further, a cooler 5 and a blower 6 are arranged in the gas laser body 1, and a plurality of anti-vibration rubbers 7 are interposed between the blower 6 and the bottom of the gas laser body 1. ing.

Further, the blower 6 uses a motor 8 shown in FIG. 5 as a drive source, and when the blower 6 is driven by this, the laser gas enclosed in the gas laser body 1 is changed to the one shown in FIG.
Is circulated as indicated by the arrow, and is supplied between the discharge electrodes 3a and 3b, and excited by the discharge between them.

Then, as shown in FIG. 5, the excited energy is extracted as a laser beam 9 to the outside through a resonator 10 which is orthogonal to the circulation path of the laser gas.

On the other hand, the lased laser gas retains most of the energy obtained by the discharge as heat, but is cooled by heat exchange in the cooler 5, returned to the blower 6, and again discharged to the discharge electrode. It is supplied between 3a and 3b.

[0008]

However, according to the above configuration, the discharge electrodes 3a, 3b and the insulating plate 4a,
When the laser gas flows through the gap 11 between the 4b, the velocity boundary layer 12 is formed because the gap 11 is straight and long (length L1).
The thick a and 12b are generated, and the velocity distribution of the laser gas is disturbed at the positions of the discharge electrodes 3a and 3b, and the flow velocity thereof becomes slow.

Further, since the velocity at which the laser gas flows in and out of the gap 11 is high, the pressure loss becomes large and the air volume becomes small.

On the other hand, when a discharge is generated between the discharge electrodes 3a and 3b, the temperature of the laser gas rises due to the heat, but as described above, the flow velocity of the laser gas between the discharge electrodes 3a and 3b is slow and the air volume is also large. Since the amount is small, the inflow of new laser gas is insufficient and cooling is delayed. Therefore, the discharge becomes unstable and the generation of the laser beam 9 becomes unstable.

In order to solve this, the discharge electrodes 3a,
It is necessary to increase the flow rate of the laser gas between 3b and increase the air volume.

Therefore, conventionally, the discharge wind speed and the air volume of the blower 6 were increased, but for that reason, it was necessary to increase the output of the drive source motor 8. However, in such a laser gas circulation system, the overall operation efficiency of the laser oscillator is reduced.

The present invention has been made in view of the above circumstances, and therefore an object thereof is to provide a gas laser oscillating device capable of stably generating a laser beam without increasing the discharge wind speed and air volume of a blower. ..

[0014]

In order to achieve the above object, a gas laser oscillator according to the present invention comprises a gas laser main body in which a laser gas is enclosed, and a blowing means for circulating the laser gas in the gas laser main body.
A cooling means for cooling the circulated laser gas and a pair of discharge electrodes provided in the circulation path of the laser gas are provided, and the discharge electrodes are located in the circulation path of the laser gas and covered with each of them. It is characterized by comprising an insulating plate having an arcuate cross section.

[0015]

According to the above-mentioned means, the flat portion of the discharge portion becomes short on the inlet side until it reaches the insulating plate having an arcuate cross section, whereby the velocity boundary layer is generated only thinly. At the position of, the velocity distribution of the laser gas becomes stable and the flow velocity becomes faster.

Further, since the inlet and outlet of the discharge section are widened and the inflow rate and outflow rate of the laser gas are slowed down, the pressure loss is reduced and the air volume is increased.

With these, the inflow of new laser gas between the discharge electrodes becomes sufficient, and cooling can be sufficiently performed.
The discharge is stable and the laser beam is also stable.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

First, FIG. 1 shows a gas laser main body 21, in which a laser gas is enclosed. or,
A cooler 22 and a blower 23 are arranged in the gas laser main body 21, and a plurality of anti-vibration rubbers 24 are interposed between the blower 23 and the bottom of the gas laser main body 21.

Furthermore, in the upper part inside the gas laser main body 21,
A pair of bases 25a and 25b are provided in parallel in the vertical direction. Discharge electrodes 26a and 26b are respectively provided at the central portions of the facing surfaces of the bases 25a and 25b, and as shown in detail in FIG. Conventional by 27b (Fig. 4)
The discharge electrodes 3a and 3b are mounted so as to be spaced apart by the same size.

Further, the insulating plate 2 covering the discharge electrodes 26a and 26b is provided on the opposing surfaces of the substrates 25a and 25b.
8a and 28b are attached. This insulating plate 28a, 28
Both b are made of an inorganic material and have an arc-shaped cross section,
As shown in FIG. 3, it is formed in a long shape along the discharge electrodes 26a and 26b.

An insulating material 29 is provided between the insulating plates 28a and 28b and the discharge electrodes 26a and 26b.
Is being filled.

In the case of such a configuration, the blower 2
3 is driven, the laser gas in the gas laser main body 21 is circulated as shown by an arrow in FIG.
28b and is excited by the discharge between the discharge electrodes 26a and 26b.

Then, the excited energy is extracted as a laser beam to the outside through a resonator (not shown) which is orthogonal to the circulation path of the laser gas.

The laser gas oscillated by the laser is sent from the space between the insulating plates 28a and 28b to the cooler 5, where it is cooled by heat exchange and returned to the blower 23, where it is again insulated. 28b (discharge electrodes 26a, 2
6b).

In the case of such an operation, the flat portion of the discharge portion on the inlet side reaches the insulating plates 28a and 28b of circular arc cross section of the substrates 25a and 25b, respectively, and the length thereof is L2. Yes, conventional discharge electrodes 3a, 3b
Also, it is shorter than the length L1 of the flat portion between the insulating plates 4a and 4b.

Here, if the thickness of the velocity boundary layers 30a and 30b generated from the inlet end of the discharge part is δ,

[Equation 1] From the equation (1), in the case of the present configuration in which the distance x of the flat portion of the discharge portion is the length L2 and is shorter than the length L1 of the conventional one, the thickness δ of the velocity boundary layers 30a and 30b is also the conventional one. 12
It becomes thinner than that of a and 12b.

When the velocity boundary layers 30a and 30b become thin in this way, they do not reach the positions of the discharge electrodes 26a and 26b, and accordingly, the discharge electrodes 26a and 26b.
At the position of, the velocity distribution of the laser gas becomes stable and the flow velocity becomes faster.

In the case of this structure, the discharge electrode 26
Since the insulating plates 28a and 28b covering a and 26b respectively have an arc-shaped cross section, the inlet and outlet of the discharge part are wider than those of the conventional discharge part, and the inflow speed and outflow speed of the laser gas are Become slow.

Here, if the pressure loss when the laser gas flows in and out of the discharge part is ΔP,

[Equation 2] From the equation (2), in the case of this configuration in which the inflow rate and the outflow rate of the laser gas are slow, the pressure loss ΔP is also smaller than that of the conventional one.

When the pressure loss becomes small as described above, the air volume also increases.

Thus, in the case of this structure, the flow velocity of the laser gas between the discharge electrodes 26a and 26b can be increased and the air volume can be increased, whereby the inflow of new laser gas between the discharge electrodes 26a and 26b. Since it can be sufficiently charged and cooling can be sufficiently performed, discharge can be stabilized and laser beam generation can be stabilized.

Moreover, in this case, it is not necessary to increase the discharge wind speed and air volume of the blower 23 as compared with those of the conventional blower 6, and it is not necessary to increase the output of the drive source motor, so that the overall operating efficiency of the laser oscillator is not increased. Can be secured high.

[0034]

As is apparent from the above description, the gas laser oscillator according to the present invention comprises a gas laser main body in which a laser gas is enclosed, and a blowing means for circulating the laser gas in the gas laser main body and a circulated laser gas. And a pair of discharge electrodes provided in the circulation path of the laser gas, and the discharge electrode is located in the circulation path of the laser gas and covers the respective arc-shaped cross sections. It is characterized by being equipped with an insulating plate, which has the excellent effect that a stable laser beam can be generated without increasing the discharge wind speed and air volume of the blower, and high overall operation efficiency can be secured. Play.

[Brief description of drawings]

FIG. 1 is an overall vertical side view showing an embodiment of the present invention.

[Fig.2] Enlarged vertical sectional side view of main parts

FIG. 3 is a perspective view of one side of the same portion.

FIG. 4 is a view corresponding to FIG. 1 showing a conventional example.

FIG. 5 is a vertical sectional front view

[Explanation of symbols]

21 is a gas laser main body, 22 is a cooler, 23 is a blower,
26a and 26b are discharge electrodes, and 28a and 28b are insulating plates.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location 8934-4M H01S 3/04 G

Claims (1)

[Claims] 1. A gas laser main body in which a laser gas is enclosed, an air blowing means for circulating the laser gas in the gas laser main body, a cooling means for cooling the circulated laser gas, and a pair of laser gas circulating passages. A gas laser oscillating device comprising: a discharge electrode; and an insulating plate positioned in the circulation path of the laser gas and covering the discharge electrode and having an arcuate cross section.