JPS5840876A - Oscillator for vertical-current carbonic acid gas laser - Google Patents

Abstract

PURPOSE:To increase the efficiency of oscillation and laser output per unit discharge length remarkably by forming a gas supply section to the oscillator and a laser pipe in double-pipe structure by using a cylindrical anode electrode and selecting the bore and length of the cylindrical electrode. CONSTITUTION:A laser gas introduced by a glass pipe 21 collides with an inner pipe 22 and is changed into turbulence, and flows to the outside in a clearance with an outer pipe 24, but it is further turned into turbulence after it passes through anodes 23 because terminals are blocked, and flows into the laser pipe from the holes 20 of the inner pipe 22 in the vicinity of the electrodes 23. One parts of the holes 20 must be formed while being opposed to the anodes 23 at that time. Since the laser gas of turbulence has various velocity distribution, velocity distribution in the section of the laser pipe is flattened, and glow discharge in the pipe is not biased in the specified direction. Glow discharge between the electrodes is extended uniformly in the pipe 24 in a gas current at high speed. The gas, discharge thereof is completed, is rapidly discharged 26, laser beams are resonated between a total reflector 27 and a semi-reflector 28, and output is extracted from the reflector 28 side.

Description

[Detailed Description of the Invention] The present invention relates to W, raw carbon dioxide laser oscillator, ji,
! The purpose is to generate a turbulent flow when the laser gas circulating at high speed passes through the discharge area in the resonator to obtain a stable discharge.

FIG. 1d - Schematic diagram of a conventional laser oscillator.

The laser gas that has entered the gas supply section 117) enters the discharge region 13 in the resonator through the gap 12, is discharged between the pin-shaped anode 14 and the cylindrical cathode 15, and resonates from the gas loss section 16. It goes out of the vessel. In this configuration, the gas supply section 11
The purpose is to stabilize the discharge by generating turbulence in the gas flow through the gap 12, but the anode 14 is bottle-shaped.
Furthermore, there is an ineffective discharge region that does not contribute to laser oscillation due to the discharge between the anode 14 and the cathode 16, which exists outside the laser beam.

In other words, in this configuration, since the anode 14 is pin-shaped, the glow discharge that had been spreading in the laser tube 17 near the cathode 16 is blown away by the laser gas circulating at high speed, and the glow discharge is caused by the pin-shaped anode. As it approaches 14, it becomes thinner and thinner, like 17 shown by the dotted line in Figure 1. Increasing the discharge volume is one of the most important factors in increasing the laser output, but by using the bottle-shaped anode electrode 14, an area where no discharge occurs is created within the laser tube. Therefore, a decrease in output cannot be avoided.

The present invention aims to eliminate the above-mentioned ineffective discharge area between the electrodes, and uses a cylindrical electrode as the anode, and has a double tube structure between the laser gas inlet to the resonator and the laser tube. Yes, cylindrical shape, oscillation efficiency and efficiency can be improved by optimally selecting the pole opening diameter and cylinder length. It is possible to dramatically increase the laser output per discharge length by -1'L. Figure 2 shows the resonance of longitudinal carbon dioxide laser oscillation 8 in an embodiment of the present invention. The outline of the structure of the organ part is shown [7/ Komono. Guided by a T-shaped glass tube 21 71)
The laser gas collides with the outer tube 24 and the inner tube 22-f)) of the laser tube with a double tube structure and generates an initial turbulent flow, causing a flow between the outer tube 24 and the inner tube 22. It flows along the outside of the inner tube 22. The gap formed between the outer tube 24 and the inner tube 22 of the laser tube is closed at the end of the laser tube, so that the laser gas passing through the anode 23 generates further turbulence, and the electrode of the inner tube 22 Opening part 2 provided near 23
0 into the laser tube. That is, the laser tube d1 has a double tube structure consisting of the outer tube 24 and the inner tube 22, and the gas flow is open and the leeward side is closed, so the gas flows through between the outer tube 24 and the inner tube 22. The laser gas enters between the outer tube 24 and the inner tube 22 of the laser tube, but is pushed back and passes through the opening 20 provided in the inner tube 22.
As the laser gas enters the center of the resonator, components in various directions occur in the flow of the laser gas, resulting in a turbulent flow.

In this case, the opening 20 needs to be provided so that at least a part thereof faces the anode 23.

The laser tube has two different diameter Pyrex tubes (outer tube 2).
4 and the inner tube 22), and the other end is attached to the inner tube 22).
It is in an open state with an opening 2o provided in the. In this way, by using the laser tube with the open end upwind of the gas flow and the closed end downwind,
The laser gas becomes turbulent when it enters the center of the laser tube.The laser gas, which has become a turbulent flow, has various velocity components as it passes through the laser tube, so the velocity at the cross section of the laser tube The distribution becomes flat. Therefore,
The glow discharge inside the laser tube will no longer flow in a particular direction and be skewed. At this time, the cylindrical anode 2
Although the glow discharge between 3 and the cathode 26 is swept away by the high-speed gas flow, it does not depend on the narrow GL range,
It spreads evenly inside the middle tube of the laser tube 24. After the discharge, the laser gas is immediately removed from the resonator through the discharge section 26. The laser beam resonates between the total reflection mirror 27 and the partial reflection mirror 28, and is emitted from the partial reflection mirror 28 side.
Y is pulled out.

Although the embodiment shown in FIG. 2 has a bilaterally symmetrical structure, the same effect can be obtained even if the structure is not bilaterally symmetrical.

Further, either piece (11) alone can function satisfactorily.

Generally, the laser output P is determined by the following equation with respect to the parameters of the laser medium.

P=r)ca□IBV Here, ηC is the extraction efficiency of the laser output, α0 is the unsaturated gain, s is the saturation parameter, and ■ is the discharge volume. Therefore, in order to increase the laser output to n, it is necessary to devise ways to increase each of these norammeters. In the present invention, the discharge volume V and the saturation point? 11L, 1T% 1W was added to the laminator Is. In a high-speed circulation type laser like this example, the saturation parameter s increases in proportion to the gas flow rate VF, so it is necessary to increase the gas flow rate to obtain high output. The electrode 23 is installed in the resonator, and by appropriately selecting the diameter of the cylinder, the gas flow rate, that is, the saturation point, can directly control the rammeter S.

As described above, in the present invention, the discharge volume within the laser tube is increased by making the electrode structure cylindrical and further combining it with a laser tube having a double tube structure to generate turbulent flow.

FIG. 4 is a system diagram showing an embodiment of the present invention.

The laser gas sent out from the blower 31 that circulates the laser gas at high speed is increased in compression heat by the heat exchanger 32 and enters the resonator 34 .

The laser gas exiting from the resonator 34 is cooled by the heat exchanger 33 to a temperature that is doubled by the discharge, and is circulated to the blower 31. In the 17 laser oscillator of the present invention, the outer diameter of the laser tube is 80 mm.

Inner diameter is 55mm, length is 60mm, gas pressure is 30TO
rr, When the discharge current is 220m per discharge length, the maximum output is 1050W, which is nearly 10 times higher than the conventional one! 1
It was done.

As explained above, the present invention inserts an inner tube into the laser gas introduction part, and combines the laser tube with a cylindrical electrode to form a double-tube structure with an open air port and uses a cylindrical electrode as an electrode. can stabilize the discharge,
It has the advantage of dramatically increasing laser output.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing the configuration of a conventional laser resonator, Figure 2 is a schematic diagram showing the configuration of a laser resonator in an embodiment of the present invention, and Figure 3 is a schematic diagram showing the overall configuration of the oscillator. It is. 20... Opening part, 21... Laser gas supply part, 22... Inner tube, 23... Cylindrical anode, 24...・Outer tube, 25...Cylindrical cathode, 26...Gas discharge part, 27...
...Total reflection mirror, 28...Partial reflection mirror, 31...
...Blower, 32...Heat exchanger, 33...
... Heat exchanger, 34 ... Resonator.

Claims (1)

[Claims] (11) A laser tube with a double tube structure consisting of an outer tube and an inner tube,
The gas supply section includes a gas supply section provided at one end of the laser tube, a gas loss section provided at the other end of the laser tube, a cylindrical anode, and a cylindrical cathode. It has a double-tube structure, and is configured so that turbulent flow occurs when the gas flow comes into contact with the inner tube, and the region surrounded by the outer tube and inner tube of the laser tube is closed on the laser gas discharge side. The cathode is formed near the closed part, the anode electrode is provided between the cathode and the gas supply part, and an opening part is provided near the anode electrode of the inner tube of the laser tube. A vertical flow carbon dioxide laser oscillator with /l'4j characteristics. (2) The laser oscillator is formed symmetrically with a common laser gas inlet! A vertical flow carbon dioxide laser oscillator according to claim 1, which has an IM' characteristic. (3) Claim 1 or 2, characterized in that the opening provided in the inner tube is provided such that at least a portion thereof faces the anode. The vertical flow carbon dioxide laser oscillator described above. (4) The vertical flow carbon dioxide laser oscillator as set forth in claim 1 or 2, wherein the gas supply section is comprised of a glass tube connected to the laser tube outer tube in a T-shape.