JPS6311795B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a waveguide gas laser that is efficient and can provide high output.

In order to obtain a highly efficient and high-output waveguide gas laser, it is necessary that the hollow waveguide that encloses the laser gas has good linearity and that the effective discharge length, that is, the length of the hollow waveguide, is long.

Conventionally, ceramic tubes are often used as hollow waveguides.
During manufacture, sintering causes warping, making it difficult to obtain long pieces with good linearity.

Therefore, conventionally, as shown in FIGS. 1A to 1D, for example, a plurality of short hollow waveguides were connected to form a long waveguide with good linearity. That is,
In Figure A, hollow waveguides 1 and 1' made of ceramic or the like are connected using a coupling flange 2. However, since the laser gas moves through the coupling flange 2, a high pressure is required for continuous discharge. There is a drawback that a trigger such as a pulse is required. Also, Figure B is
Although the hollow waveguides 3 and 3' are coupled through the Brieuster window 4, it is difficult to align the optical axes of the hollow waveguides 3 and 3', and even if the optical axes of the two are slightly misaligned, , the drawback is that a significant increase in coupling loss occurs. In addition, C in the same figure shows hollow waveguides 5 and 5'.
are coupled through a window 6 coated with anti-reflection coating, but like the one shown in Figure B, even a slight deviation of the optical axis causes a considerable increase in coupling loss. There are drawbacks. In addition, in FIG. D, the hollow waveguides 7 and 7' are fixed using a coupling cap 8 as shown in the figure, and the hollow waveguides 7 and 7' are coupled via a folding mirror 9.
Although the effective discharge length is lengthened and the actual length is shortened, the coupling cap 8, which is equipped with an adjustment function (not shown) such as airtightness and changing the angle of the folding mirror 9, is expensive. Another drawback is that it is difficult to manufacture.

The present invention has been made to improve the above-mentioned drawbacks, and its purpose is to improve the length of a waveguide gas laser in which a plurality of short hollow waveguides are combined to form a long waveguide. The purpose of this invention is to reduce the coupling loss between the short hollow waveguides and increase the efficiency of the waveguide gas laser. Examples will be described in detail below.

FIG. 2 is a cross-sectional view of an embodiment of the present invention,
Hollow waveguides 10 and 10' are connected using a dielectric waveguide 11 whose end surfaces are perpendicular to the optical axis and coated with anti-reflection coating. _For example, ZnSe, Ge,
Use KRS-5 etc. In this case, it is necessary to bond the hollow waveguides 10, 10' and the dielectric waveguide 11 using an adhesive or the like to provide airtightness.

In this way, in this embodiment, the hollow waveguides 10, 1
0' are coupled using the dielectric waveguide 11, even if there is some axis misalignment between the hollow waveguides 10 and 10', the coupling loss can be made extremely small. Since laser gas is sealed in each hollow waveguide 10, 10', there is no need to apply a high-voltage pulse trigger when causing continuous discharge.

FIG. 3 is a sectional view of another embodiment of the present invention,
Hollow waveguides 12, 12' arranged in parallel,
U with anti-reflection coating on both end faces perpendicular to the optical axis
It is connected using a dielectric waveguide 13 in the shape of a letter to increase the effective discharge length and shorten the actual length.
This corresponds to the conventional example shown in Figure D. Note that in this case as well, the hollow waveguides 12, 1
2′, connect the dielectric waveguide 13 with adhesive or the like,
It is necessary to provide each hollow waveguide 12, 12' with airtightness, and the U-shaped dielectric waveguide 13
It is desirable that the radius of curvature of is determined in consideration of transmission loss.

In this embodiment, the hollow waveguides 12, 12' are coupled via the U-shaped dielectric waveguide 13, so the configuration is simpler than the conventional example shown in FIG. 1D. In addition, the hollow waveguide 1 can be
The coupling loss between 2 and 12' can be made extremely small.

In addition, in the embodiment, the case where two short hollow waveguides are coupled is explained, but the case where three or more short hollow waveguides are coupled is also possible.
You can do the same thing as in the case of two pieces.

As explained above, the present invention combines a plurality of hollow waveguides using a dielectric waveguide whose end surfaces are perpendicular to the optical axis and coated with anti-reflection coating to form a long waveguide. Therefore, even if there is some deviation in the optical axis of each hollow waveguide, the coupling loss between the hollow waveguides can be made extremely small. Therefore, there is an advantage that a high-output and efficient waveguide gas laser can be constructed.

[Brief explanation of the drawing]

Figures 1 A to D are cross-sectional views of the conventional example, Figures 2 and 3
The figures are cross-sectional views of different embodiments of the invention. 1, 1', 3, 3', 5, 5', 7, 7', 10,
10', 12, 12' are hollow waveguides, 2 is a coupling flange, 4 is a Brewster window, 6 is a window, 8 is a coupling cap, 9 is a folding mirror, and 11, 13 are dielectric waveguides.

Claims (1)

[Claims] 1. A waveguide gas laser in which a laser gas is filled in a hollow waveguide includes a waveguide in which a plurality of hollow waveguides are coupled by a dielectric waveguide whose end face is coated with anti-reflection coating and whose end faces are perpendicular to the optical axis. A waveguide gas laser characterized by: