JPS6181683A - Ion laser tube - Google Patents

Abstract

PURPOSE:To prevent generation of powder and eliminate difficulty in attaining accuracy of straightness and internal diameter of fine tube by accommodating a fine tube block having ceramic disk into a ceramic pipe. CONSTITUTION:A metal cylindrical member 2 is engaged with the periphery of ceramic disk 1 in order to transfer heat generated in the ceramic disk 1 to a ceramic pipe 5 which becomes an outer case. For this purpose, a degree of contactness (heat conductivity) which is almost equal to the brazing can be obtained by designing outer diameter of disk 1, internal diameter of pipe 5, diameter and thickness of metal cylindrical member 2, considering material and temperature rise.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to the structure of an ion laser tube using a gas such as argon or krypton, which emits high-power laser output through large current discharge.

(Prior art and its problems) Ion lasers, which perform laser oscillation by transitions between energy levels of ionized gases such as argon and krypton, need to increase ion density to achieve high output. To achieve this, it is necessary to pass a large current exceeding IOA through a thin tube with an inner diameter of 1 to 3 m.The tube material and structure that can withstand such a large current must have heat resistance, heat radiation, etc. There are various restrictions.

Conventionally, the structure of this capillary material and #l tube.

Several methods are used, and the typical one is a structure in which graphite disks with a hole for the thin tube are lined up with an insulator in between, and these are housed in a quartz tube. Cooling is done by absorbing the radiant heat of the disk from outside the quartz tube with water. Another representative example is BeO
This method uses a ceramic thin tube, and cooling involves directly cooling the outer periphery of the BeO ceramic tube with water, utilizing the thermal conductivity of the BeO waste.

However, graphite capillary tubes tend to produce powder during use, which can reduce the output of the blue metal window of the laser tube, and has drawbacks such as restrictions in transportation. In addition, since BeO, which has BeO7-lamiramic tubular properties, is used, supply sources are limited, and it is not only extremely expensive, but also difficult to manufacture long and thin tubes while maintaining the accuracy of the inner diameter and straightness. The problem is that it is difficult.

Recently, US Patent No. 437A600 discloses a capillary structure in which a tungsten disk is brazed into an alumina ceramic pipe via a cup-shaped copper plate. Although this structure eliminates the above two drawbacks, it has the serious drawback that the oscillation efficiency is about 30% lower than that of conventional laser tubes due to the thinness of the disk and the low occupation rate of the thin tube over the entire length. .

The purpose of this invention is to eliminate the drawbacks of conventional ion laser tubes, such as powder generation and the difficulty in determining the straightness and inner diameter of the thin tube, and to improve the oscillation efficiency without significantly reducing the effective length of the thin tube. It is an object of the present invention to provide an ion laser tube in which cooling efficiency of a thin tube portion is improved by preventing the decrease in the cooling efficiency.

(Means for Solving the Problems) The ion laser tube of the present invention includes a disk made of a ceramic material having a small hole constituting a thin tube near the center and a plurality of small holes serving as a gas return bus around the periphery. A large number of thin tube blocks made of metal cylindrical members inscribed or brazed on the outer periphery of the ceramic disk are arranged in series using a method that arranges the small tube holes in a straight line, and these blocks are made of metal. It is preferable that the cylindrical member has a thin tube section housed in a ceramic pipe having an inner diameter in which the outer diameter of the cylindrical member is inscribed. As the material of the ceramic disk, beryllia porcelain, silicon carbide, boron nitride, alumina porcelain, etc. can be used.

(Example) Next, the present invention will be explained in detail using the drawings.

FIG. 1 is a sectional view of an ion laser tube showing one embodiment of the present invention. The ion laser tube consists of a ceramic disk 1.
A thin tube part consisting of a metal cylindrical member 2 held at the outer part, a ceramic 1$13 for aligning the small holes in the center of the disk, and an insulator 4 for determining the distance between the disks 1; Ceramic pipe 5 that accommodates this thin tube part
, an anode 6 and a cathode 7 arranged at both ends of the thin tube section, metal pipes 10 and 10' vacuum-tightly sealed at both ends of the ceramic pipe 5, and a glass container 11, 11 and glass welded to these. It has blue female windows 12, 12' provided at the ends of the containers 11, 11'.

The material for the ceramic disc 1 has high thermal conductivity.
Beryllium porcelain, silicon carbide, boron nitride, etc. are suitable, but for laser tubes with low current density, alumina ceramic etc. may also be used. As shown in the cross section of FIG. 2, this ceramic disk 1 has a central hole 21 which becomes a thin tube, a hole 22 into which a ceramic rod for alignment is inserted. and a plurality of small holes 23 for gas return baths. A metal cylindrical member 2 is fitted around the ceramic disc 1, and has the role of transmitting the heat generated in the ceramic disc 1 to the ceramic pipe 5, which serves as an envelope.For this purpose, it is fitted as closely as possible. In order to improve accuracy, it is ideal to have a dimensional tolerance that is straight during the fitting process or to use a soldered structure. However, when the laser operates, the ceramic disk 1 becomes high temperature, and the gap between the disk 1 and the inner diameter of the ceramic pipe 5 decreases due to thermal expansion, so that the metal cylindrical member 2 is compressed into this gap 1. Therefore, it is not necessary to strengthen the degree of contact in a cold state, but the dimensions such as the outer diameter of the ceramic disk 1, the inner diameter of the ceramic pipe 5, the diameter and wall thickness of the metal fitting cylindrical member 2 are determined by the respective materials and heat resistance during operation. By taking into account the rise, etc. in the design, it is possible to obtain a degree of contact (thermal conductivity) almost equivalent to brazing. Ceramic pipe 5 has cost and characteristics as a vacuum container.

An alumina porcelain vibrator is ideal, but a porcelain vibrator with a brazing finish or IJ+J is also acceptable.

Copper, molybdenum, or the like is used for the anode 6, and contact with the ceramic pipe 5 is made through a cylindrical metal like the ceramic disk. The above-mentioned ceramic disk 1 and @pole 6 are configured by the ceramic rod 3 passing through the three centering holes 22 so that the large amount of thin tubes at the center are aligned. An insulator pipe 4 is inserted between the disks and between the anodes to maintain these intervals. The thin tube section consisting of the anode and ceramic disk group as described above can be formed by inserting the metal pipe 10 for sealing into the ceramic pipe from the anode side before brazing it, by the spring force of the metal cylindrical member. It can be easily inserted while contacting the inner wall of the ceramic pipe. Of course, if the metal pipe is brazed to the outside of the ceramic pipe, insertion after brazing is also possible.

The ceramic pipe 5 can achieve contact by metal spring force or compression due to the difference in thermal expansion, so it does not require strict inner diameter accuracy, and the straightness of the thin tube is also similar to the ceramic rod 3. This is achieved by reducing the accuracy.

Of course, it is also possible to align the disks without using ceramic rods by increasing the straightness of the pipe.

After the above structure of the thin tube part is assembled, the glass container 1
1, 11' are sealed and roughly assembled into a stem (consisting of a part of the glass container and lead wire 9 in FIG. 1), a cathode 7, an anode lead 8, and a Brewster window 12.12'.
etc. are enclosed in order.

It goes without saying that these glass containers can be replaced with ceramics and metals.

The ion laser tube assembled as described above is fixed in the solenoid coil at the ceramic pipe section with a watertight seal using an O-ring, and the heat generated by the discharge is transferred to the inner wall of the solenoid coil by heat conduction through the ceramic pipe. It is cooled by cooling water flowing through.

(Effects of the Invention) As explained above, by using a ceramic disk, the present invention does not generate powder unlike laser tubes using conventional graphite disks, and the ceramic pipe has a low requirement for straightness. By being able to use tungsten discs, there is no need to use expensive parts, and the occupancy rate of the thin tubes can be increased compared to those using tungsten discs, so the laser oscillation efficiency can be increased. Furthermore, since the generated heat can be efficiently removed by thermal conduction, the pressure of the sealed gas can be relatively increased compared to graphite discs, which is advantageous in terms of life. Furthermore, there is no complicated brazing process like the tungsten disc type, and it can be completed with a simple assembly process like the graphite disc type, so it has great cost advantages.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the ion laser tube of the present invention, and FIG. 2 is a sectional view showing an example of the shape of a ceramic disk. 1...Ceramic disk, 2...Metal cylindrical member, 3...Ceramic rod, 4...
...Insulating pipe, 5 ... Ceramic pipe, 6 ... Anode, 7 ... Cathode, 8.
... Anode lead-in line, 9 Old... Cathode lead-in line, 1
0.10'・・・Metal pipe, 11, 11'・
...Glass container, 12, 12'...Blue metal window, 21...Small tube hole, 22...
...Alignment hole, 23...Small hole for gas return bath.

Claims (1)

[Claims] For thin tubes, it consists of a ceramic disk with a small hole near the center that forms the thin tube, and multiple small holes around the periphery that serve as a gas return bus, and a metal cylindrical member inscribed or brazed on the outer periphery of this disk. A structure in which a large number of blocks are arranged in series using a method such that the small holes for the thin tubes are arranged in a straight line, and housed in a ceramic pipe having an inner diameter inscribed with the outer diameter of the metal cylindrical member. An ion laser tube characterized by having a thin tube section.