JPS60219782A - Gas laser tube - Google Patents

Abstract

PURPOSE:To obtain the titled tube of low cost and high quality by a method wherein a discharge path fine tube forming a discharge path is made of silicon carbide. CONSTITUTION:The fine tube made of silicon carbide forms a discharge path between the cathode 11 and the anode connected via encapsulating trays 2 and 3 respectively. Heat dissipating fins 6 are bonded to the outer periphery of the tube 1, and the heat evolving in the encapsulating trays 2, 3, and 7 and the anode 5 is dissipated via fins 6 by the air fed in from a fan not illustrated. A cathode valve 4 includes the cathode 11 and contains argon gas. Besides, a return path 9 for the argon gas connects the valve 4 with an anode valve 8.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field to which the invention pertains) The present invention relates to helium-neon, argon, krypton,
The present invention relates to a gas laser tube that produces laser oscillation using excitation by discharge of a gas such as carbon dioxide gas.

(Prior Art) Generally, a gas laser tube is a discharge path thin tube (hereinafter referred to as a thin tube) made of glass or ceramic that forms a discharge path.
It is a cylindrical sealed tube whose main components are a pair of windows located at both ends, an anode, and a cathode, and the inside of the tube is filled with helium/neon, argon, krypton, carbon dioxide gas, etc.

Incidentally, in order to increase the output of the gas laser tube, it is necessary to increase the density of the discharge current, but in this case, energy loss increases due to collisions of the discharge gas on the walls of the thin tube. For this reason.

The temperature of the tube wall of the capillary increases significantly, causing destruction of the capillary and a decrease in oscillation efficiency.

For these reasons, in the case of high-power lasers such as carbon dioxide lasers and argon lasers, heat dissipation in the gas laser tube, especially in the thin tube section, becomes an extremely important issue.

Therefore, when the output is relatively large, a conductive perforated disk made of a high melting point metal such as tungsten or graphite is placed inside a quartz glass tube with excellent heat resistance and thermal shock resistance via an insulating spacer. Gas laser tube with laminated thin tube parts and Be+71J with excellent thermal conductivity and airtightness
A (compared to acids) There are two common types of gas laser tubes that use a ceramic thin tube that also serves as the surrounding air. In both cases, the envelopes are immersed in cooling water pressure.

In addition, when the output is relatively small, a gas laser tube is generally used, which is a thin ceramic tube made of PEIJ 177 with venting fins provided on the outer wall, and is air-cooled by a fan.

Among these, beryllia ceramic capillaries have various advantages, but have extremely serious drawbacks in manufacturing.

Firstly, beryllia ceramic is a legally regulated substance and must be processed and handled with great care.Secondly, it is extremely expensive and cannot be manufactured in long pieces or in the required shapes. The third problem is that the mechanical strength is weaker than that of alumina ceramics and the like, and it is impossible to reduce the weight. In addition, there are many manufacturing problems derived from these drawbacks, and there have been attempts to switch from beryllia ceramic to other materials.

(Object of the Invention) The present invention replaces beryllia ceramic with silicon carbide in order to solve the drawbacks of the conventional gas laser tube using ceramic capillary tubes.

Our goal is to provide high-quality gas laser tubes that are relatively inexpensive and have no legal restrictions.

The present invention will be explained in detail below.

(Structure and operation of the invention) FIG. 1 shows a cross section of an argon gas laser tube according to an embodiment of the invention. In Fig. 1, 1 has a length of 66 mm.

It is a thin tube made of silicon carbide with an outer diameter of 16 mm and an inner diameter of 1.02 mm, and forms a discharge path between a cathode 11 and an anode 5, which are connected via sealed silicon 2 and 3, respectively.

A radiation fin 6 is joined to the outer periphery of the thin tube 1. Enclosure dish 2, 3.7. Heat generated at the anode 5 is dissipated through the heat radiation fins 6 by air fed by a fan (not shown).

The cathode bulb 4 includes a cathode 11 and stores argon gas. In addition, the argon gas return path 9 is
A cathode bulb 4 and an anode bulb 8 are connected. At both ends, so-called Brewster windows 10 forming a pre-aster angle with respect to the central axis of the discharge path are joined to face each other.

Next, a method for manufacturing an argon laser tube having the above structure will be described.

Silicon carbide has high thermal conductivity and excellent high-temperature strength and mechanical strength, making it suitable as a material to replace beryllia ceramic. However, since silicon carbide does not contain oxides, conventional silicon carbide cannot be metallized and is difficult to join by brazing.
It was confirmed that it is possible to directly braze silicon carbide using e-brazing filler metal without metallizing it.

Therefore, the enclosure dish 2 shown in FIG. Anode 5. Enclosure dish 3. Tube 1. Braze the enclosure plate 2 and radiation fins 6 @'49Ti
Vacuum brazing was performed using -49Cu-2Be at a brazing temperature of 1015C. Thereafter, glass processing was performed using a conventionally known method to complete the argon laser tube 20.

Although this example describes an air-cooled argon laser tube,
Since the water-cooled argon laser tube has the same brazing structure, it can be easily manufactured using the above manufacturing method.

Furthermore, it goes without saying that vacuum brazing of silicon carbide is possible even if pure titanium is used instead of 49Ti-49Cu-2Be.

In this way, we were able to manufacture an argon laser tube with excellent airtightness and thermal shock resistance by vacuum brazing the thin tube made of silicon carbide and the metal parts using a titanium-based brazing material.

(Explanation of Effects) As described above, according to the present invention, compared to beryllia ceramics conventionally used as thin tubes, (1) there are no restrictions on handling, and (2) complicated processes are not applied to the surface of the thin tubes. The required metallization process can be omitted, (3) various machining processes can be performed, (
4) has extremely high mechanical strength and thermal shock resistance (51) It is possible to provide a high quality Kaslas laser tube using inexpensive silicon carbide.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a gas laser tube for explaining the present invention in detail. 1... Thin tube using silicon carbide or silicon carbide/beryllium oxide composite material, 2.3.7... Enclosure dish, 4... Cathode bulb, 5... ···anode,
6... Radiation fin, 8... Anode bulb, 9... Return path, 10... Brewster window, 11... Cathode, 20...
gas laser tube.

Claims (1)

[Claims] 1. A gas laser tube having a thin tube forming a discharge path between an anode and a cathode, characterized in that the thin tube is made of silicon carbide.