JPH0417378A - Ring resonator for iodine laser - Google Patents

Abstract

PURPOSE:To obtain a plurality of laser beams from a single resonator by incorporating a laser medium in an optical loop composed of at least three mirrors, of which two are half mirrors. CONSTITUTION:A ring resonator includes a rectangular optical loop formed of four mirrors 11, 12, 13, and 14 that are placed on the apexes of a rectangle. The mirrors 11 and 12 are concave half mirrors. A laser medium 17, having two optical windows 15 and 16 at its ends, is inserted in the optical path between the mirrors 11 and 12. Laser oscillation takes place by the transfer of energy from exciting oxygen to iodine, and laser light is emitted from the ring resonator. The laser light goes through the optical windows 15 and 16 to circulate the rectangular loop, and laser beams are sent outside through the mirrors 11 and 12. Since laser light is incident to the half mirror 11 from perpendicular directions, two beams LB1 and LB2 are obtained.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an iodine laser device for generating iodine laser light.

[Conventional technology]

Many materials such as ruby, glass, YAG, or COz have been used as sources of laser light, but in recent years, chemically excited iodine lasers (Chemically Pu
mped Iodine La5er: CPIL)
Research and development has progressed, and a high-power laser with a wavelength of 1.315 μm has been successfully generated. This CPIL has the advantages that it does not require electrical energy as a pumping source for laser oscillation, can perform laser oscillation with chemical fuel, and has a relatively simple structure.
It is widely applied industrially in processing including micro removal, welding and surface treatment. The basic principle of CPIL is an energy transfer reaction expressed by the following equation. Oz"('A) +I(P3/Z): 0x(3
Σ) +1” (P l /2) ・(1) Here, 0
2''('Δ) represents oxygen in an excited state, and I'' (P, /□) represents iodine in an excited state. In the reaction of equation (1), the reaction speed from the left side to the right side is fast, so pumping is performed efficiently, and I''(P+
/z) is generated. This I/PI/□) becomes a laser medium and generates a laser beam with a wavelength of 1.315 μm. Here, the most important thing is the pumping source 0□I
The question is how to efficiently generate (IΔ). The most efficient method currently known is the decomposition reaction of hydrogen peroxide shown by the following formula. HzO, + 2NaOH+ C1z→O,” + 2H
zO+ 2NaC1" (2) Based on this principle, the configuration of a conventional iodine laser device is shown in FIG. 1. In the figure, numeral 1 is an excited oxygen generating section, 2 is a trap, and 3 is a resonator. The excited oxygen generating unit 1 bubbles chlorine gas into an alkaline high concentration hydrogen peroxide aqueous solution contained therein.
``('Δ) is generated here, and it occurred here.2''
The gas containing ('Δ) is led to the trap 2 via the duct 4, where water is removed. This gas is
It is sent to the resonator 3 via the duct 5, during which time it receives iodine injection from the injector 6 provided in the duct 5. The resonator 3 includes two concave mirrors arranged opposite to each other on a common axis, and resonates by repeating reflection between the concave mirrors to form a desired laser beam. One of the two concave mirrors is a half mirror, and the laser beam is transmitted through this half mirror and extracted to the outside.

[Problem B that the invention attempts to solve]

As described above, in the conventional iodine laser device, the laser beam can only be extracted from one end of the resonator 3 along the axis that coincides with the central axis of the resonator 3, and the laser beam can be used simultaneously at multiple positions. In order to meet this demand, additional equipment such as a beam splinter is required. Furthermore, splitting using a beam splitter has the disadvantage that when the supply of laser light is cut off at a certain splitting point, power fluctuations occur at other splitting points. This invention was made in order to eliminate the drawbacks of the conventional iodine laser device as described above. Laser light can be extracted from multiple output points, and fluctuations in the output state at each output point are different from other output points. It is an object of the present invention to provide an iodine laser device that is improved so as not to affect the output state at the output point.

[Means to solve the problem]

In the iodine laser device of the present invention, the two boundaries separating the optical axis of the laser medium and the optical loop are both optical windows, and the laser medium is composed of at least three mirrors, at least two of which are half mirrors. integrated into the optical loop.

[For use]

Laser light extracted from the laser medium circulates within this loop and is extracted to the outside from the half mirror that constitutes the loop. When a triangular optical loop is made up of three mirrors including two half mirrors, laser light can be extracted from two positions simultaneously, and each half mirror has two directions. Since laser light is incident, four different laser light outputs can be obtained.

【Example】

An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows a main part of a ring resonator constituting the present invention, and this ring resonator is provided at the position of the resonator 3 in the iodine laser device shown in FIG. The ring resonator of this example forms a rectangular optical loop with four mirrors 11, 12, 13 and 14 placed at each vertex of the rectangle, of which mirrors 11 and 12 are concave half mirrors. . And mirror 1
Two optical windows 15 and 1 are placed on the optical path between 1 and 12.
A laser medium 17 partitioned by 6 is provided. This laser medium 17 has a laser gain formed in substantially the same way as the resonator 3 shown in FIG. 1, and is placed at the same position as the resonator 3. In the iodine laser device configured in this way, the iodine is excited by an energy transfer reaction from excited oxygen to iodine to cause laser oscillation, thereby generating laser light in the entire ring resonator, and this laser light is It exits through the optical windows 15 and 16 of the laser medium 17, circulates within the rectangular optical loop of the ring resonator, and passes through the mirrors 11 and 12.
is passed through and taken out to the outside. Since laser light enters the half mirror 11 from two directions perpendicular to each other,
Two laser beams LBI and LB2 with different directions
is output. Similarly, the half mirror 12 also outputs two laser beams LB3 and LB4. Since these laser beams have extremely little interference with each other, even if their output state is changed, it will hardly affect the states of other laser beams. Although the above embodiment shows an example in which a rectangular optical loop is formed, a triangular optical loop can also be formed using three mirrors, and a triangular optical loop can be formed using five or more mirrors. It is also possible to form a rectangular optical loop. Furthermore, since this optical loop ring can be configured separately from the laser medium, it is possible to attach it externally to an existing laser medium to change it to a multi-output one. FIG. 3 shows another embodiment of the invention. In this example,
In the ring resonator shown in FIG. 2 configured by four mirrors 11-14, any mirror, for example 11
and 12, means 21 and 2 for varying the reflectance thereof.
2 are respectively provided, and a gain means 23 is provided at an arbitrary position on the optical path. Any number of gain means 23 can be provided on the optical path of the ring resonator. Means 21 and 22 for changing the reflectance provided on the mirrors 11 and 12 adjust the intensity of the output laser beam LBI~4 according to the reflectance, thereby providing a laser beam with an intensity suitable for the application. The gain means 23 then compensates for changes in the laser intensity within the ring resonator due to changes in the reflectivity in the mirrors 11 and 12.

【Effect of the invention】

As explained above, according to the present invention, a plurality of mirrors are combined to form a triangular, quadrangular, or more polygonal optical loop, and a resonator is incorporated into this optical loop to form a single It becomes possible to extract multiple laser beams from the resonator.

[Brief explanation of drawings]

FIG. 1 is a system diagram showing a conventional iodine laser device, FIG. 2 is an explanatory diagram showing a ring resonator according to one embodiment of the present invention, and FIG. 3 is an explanatory diagram showing a ring resonator according to another embodiment of the present invention. It is a diagram. In the figure, 11, 12, 13.14 are mirrors 15.1
6 is an optical window, 17 is a laser medium, 21 and 22 are means for changing reflectance, and 23 is a gain means. 11N1 diagram

Claims (1)

[Claims] This device injects iodine into a gas containing oxygen in an excited state and generates an iodine laser beam by receiving the supply of this mixed gas. A ring resonator of an iodine laser device including a laser medium with two optical windows facing each other and arranged on an optical path in a loop.