JPS6047483A - Gas laser tube - Google Patents

Abstract

PURPOSE:To simplify the manufacturing processes for gas laser tubes as well as to facilitate works in the manufacturing processes by a method wherein the Brewster window mounting part of the gas laser tube is formed of a thick transparent glass and a powdered glass molded tube, which interconnects with the thick transparent glass. CONSTITUTION:Glass powder 24 is thrown is proper quantity between the external surface of a coil 23 and the inner wall of a jig 22. An oval and thick transparent glass 16, which is to be used as a Brewster window mounting face and is one formed by cutting a thick glass tube in a prescribed size, is placed on the glass powder 24. Moreover, a molding type jig 25 is put on, a weight 26 is placed on, a heating and a baking are performed, and a Brewster window mounting tube, whose Brewster window mounting part is the glass 16 and which consists of the glass 16 and a powdered glass molded tube 12 to interconnect with the glass 16, is manufactured. Accordingly to such a structure, a highly and technically skilled proficiency degree is not needed. As a result, the manufacturing processes can be simplified, and at the same time, works in the manufacuring processes can be also simplified as well.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an external mirror type gas laser tube in which one or both ends of the laser tube envelope are hermetically closed by a Brewster window.

In the external mirror type gas laser tube, for example, as shown in FIG.
Window panels 6 and 7 are hermetically bonded to the Brewster's angle cut surfaces at the ends of the mounting tubes 2 and 3 to form a vacuum envelope. A voltage is applied between the cathode 8 provided along the inner circumferential surface of the thick tube 1 and the anode 9 provided near the Brewster window 7 of the attached tube 3. A discharge plasma is formed within a discharge capillary tube 10 supported at opposite ends, and an optical resonator is formed of a pair of mirrors (not shown) provided outside Brewster windows 6 and 7 with this laser tube as the center. Laser oscillation is caused by the action of

The vacuum envelope of such an external mirror type gas laser tube has conventionally been manufactured by the following method. First.

Manufactures Prunimeta window mounting pipes. To explain according to FIG. 2, prepare a glass tube with a desired inner diameter of 4 mm, for example, as the through hole 11 for the passage of the laser beam, and a glass tube with a wall thickness of 5.5 mm, which is necessary for welding the Brewster window plate. do. Since the dimensional accuracy of thick-walled glass tubes made of ordinary material is not good, the thick-walled glass tube is baked and softened with a gas burner, and the thick-walled glass tube 12 is processed and corrected to accurately match the desired dimensions. That is, cut at tl. Next, thick-walled pipe 12
The wall thickness 1 has the same outer diameter (tsm) and the inner diameter is the guide hole 13.
．． It was welded to one end of a five-cylinder thin glass tube 14, and then the glass tube was cut to a predetermined dimension t2.

The end of the thick-walled tube is roughly cut at Brewster's angle, and the cut surface 15 is polished to make it transparent.

In order to connect the Brewster mounting tube made in this way to the large tube section of the envelope on the opposite left side of the anode, a short glass tube -gi protruding from the center of the stem flange that closes the large tube section.
, Connect the thin glass tube part of the Brewster attachment tube to i. On the one anode side, a Brewster window mounting tube was welded in the same way as on the left side, and an extension tube was arranged to connect a thin glass tube communicating with the Brewster window via the stem. Further, a discharge capillary tube 10 is concentrically welded to the inner peripheral portion of the tip of the extension tube.

The welded stem of the Brewster attachment tube is combined with both ends of the thick tube part of the envelope with the cathode placed inside, and the stem is sealed by heat.
Thereafter, a window plate is airtightly bonded to the Brewster corner end face of the Brewster window mounting tube using an organic adhesive or low melting point glass to form a laser tube. For such laser tubes, especially in the manufacturing process of Brewster window-mounted tubes, the raw glass tube is repeatedly processed and corrected by baking and stretching in order to make it into a specified thick-walled tube, and then Thin-walled glass tubes with the same outer diameter were connected, and a process of shaping the connected portion was necessary in order to make the connected part have the predetermined outer diameter again. Therefore, since this series of work processes is completely manual processing, it not only necessarily requires a large number of man-hours, but also requires a high degree of skill proficiency in glass processing work, which ultimately reduces yield and efficiency. This had the disadvantage of lowering the performance and increasing costs.

In addition, alignment work to make the thick-walled tube through hole of the Brewster window attachment tube coaxial with the discharge capillary axis at the tip of the stem, which forms part of the envelope, requires a high degree of skill and a large amount of man-hours. In addition, there were drawbacks such as deformation of the Brewster angle surface due to heating during processing. In order to improve this drawback, as shown in Fig. 3, instead of using the conventional material, that is, ordinary glass tube, powdered glass is used as the material, and thick-walled tube 12 and thin-walled tube 14 of the Brewster window mounting part are used. A Brewster window mounting tube has been proposed which is formed using a powder glass molding method, in which the Brewster window mounting surface 15 is molded in a continuous manner. Compared to Brewster window mounting tubes made using the powder glass molding method, the use of graphite molds makes it possible to integrate the parts, which also makes mass production easier. It has been improved so that it can be done. However, since the material is powdered glass, the Brewster mounting surface becomes rough and microbubbles occur after the glass is melted due to the characteristics of the glass. As a result, after bonding the Brewster window plate to the Brewster window mounting surface, uniform adhesion could not be obtained, resulting in leakage and a decrease in yield.

It is an object of the present invention to solve the difficulties in manufacturing conventional external mirror type laser tubes, especially Brewster window mounting tubes, and to create a laser suitable for mass production that has a Brewster window mounting section with good dimensional accuracy and is difficult to leak. Its purpose is to provide the structure of the pipe.

Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 4 shows a Brewster window mounting tube according to the present invention, in which the tube connection is omitted and the Brewster window mounting portion is comprised of a thick-walled transparent glass tube and a molded powder glass tube that communicates with the thick-walled transparent glass tube. FIG. 4 shows the manufacturing method of the Brewster window mounting pipe. Referring to FIGS. 4 and 5, after placing the graphite mold jigs 21 and 22 in combination on the jig holder 20, the inner diameter 11 located at the center of the mold jig 21 is
．． A hole with a diameter of 0.5 mm is formed in advance into a shape in which the guide hole 13 and the through hole 11 are integrally connected.
A coil 23 made of iron wire is arranged. Thereafter, an appropriate amount of borosilicate powder glass 24 is placed between the outer surface of the coil 23 and the inner wall of the jig 22. On top of the borosilicate powder glass 24, a glass tube with an outer diameter of 15 Nn and a wall thickness of 5 mm was cut into a length of 6 mm and an angle of 33.3 degrees to form an elliptical shape. An elliptical thick-walled transparent glass 16 is placed. Furthermore, a graphite molding jig 25 is covered, a weight 3002 is placed on it, and the temperature is kept at 100° C. for 15 minutes in a nitrogen gas atmosphere to perform heating and baking. After cooling, the shape of the guide hole and the through hole are integrally connected. A Brewster window mounting tube was manufactured by unraveling and extracting the iron coil 23 which had been formed into a molded shape, and comprising a powdered glass molded tube in which the Brewster window mounting portion was made of thick-walled transparent glass and communicated with the thick-walled transparent glass.

The Brewster window-mounted tube manufactured in this way can be manufactured using a conventional laser tube using ordinary transparent glass or a Brewster window-mounted tube in which a thick-walled tube and a thin-walled tube are integrated using powdered glass. It was attached to one end of the thick tube part of the envelope in exactly the same way as the method. After that, adjust the outside diameter to 12 on the Brewster window mounting surface.

A glass substrate with a thickness of 2cm is B20. - Airtightly weld with PbO-based low melting point glass, and after bonding, follow the usual method to exhaust,
A sealed gas laser tube was manufactured by baking and gas injection.

From the above explanation, the structure of the Brewster window mounting pipe of the present invention does not require a high degree of technical skill, and not only can the manufacturing process be simplified and the work is easy, but also the Brewster angle cut surface Accurate formation, and since the Brewster mounting surface is normally made of thick glass, there is no foaming or roughness, and good surface precision is achieved, making it possible for the glass substrate to adhere uniformly, improving not only reliability but also yield. It is also improved and becomes cheaper. Furthermore, since the Brewster window mounting pipe portion and the stem flange are integrated and accurately arranged, the output of the gas laser tube is improved, and therefore, it is possible to easily manufacture the gas laser tube and obtain a low-cost gas laser tube.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a conventional external mirror type gas laser tube, Fig. 2 is a cross-sectional view of a Brewster window-mounted tube using ordinary glass, which is a conventional manufacturing method, and Fig. 3 is a cross-sectional view of a conventional manufacturing method. Cross-sectional view of Brewster window mounting tube made of powdered glass, No. 4
The figure is a cross-sectional view of the Brewster window-mounting tube according to the present invention, and FIG. 5 is a cross-sectional view for explaining the manufacturing process of the Brewster window-mounting tube of FIG. 4 by the powder glass molding method. 1... Laser tube envelope thick tube part, 2, 3...
...Brewster window mounting pipe, 4,5...Stem flange, 6.7...Brewster window plate S
8...Cathode. 9...Anode, No.....Discharge capillary, 11
...Thick-walled pipe, 13.
...Guidance hole, 14...Thin-walled tube, 15...
...Brewster window mounting surface, 16...Oval thick transparent glass, 23...Pure iron coil, 26
...Powdered glass.

Claims (1)

[Claims] In an external mirror type laser tube in which one end or both ends of a gas-tight vacuum envelope containing a built-in discharge tube forming a discharge path between a cathode and an anode are closed by a Brewster window, the Brewster A gas laser tube characterized in that the window mounting tube comprises a thick-walled transparent glass tube to which a Brewster window is attached and a powder glass molded tube communicating with the thick-walled transparent glass tube.