JPH0779040A - Unstable laser resonator - Google Patents

Abstract

PURPOSE:To grasp the mutual positional relation between a concave mirror and a convex mirror easily without giving damages, etc., to a beam detector by a method wherein the beam detector is so provided as to receive a detecting laser beam oscillated from an unstable resonator for detection. CONSTITUTION:If a light 5 is generated between a concave mirror 9 and a convex mirror 11, the light 5 is resonated by the mirror surfaces 8 and 10 of both mirrors 9 and 11 to generate a high power laser beam 6 oscillated outside from the mirror surface 8. At the same time, the light 5 is resonated by the mirror surfaces 12 and 14 of both mirrors 9 and 11 to generate a low power laser beam 17 which enters a beam detector 7 from the mirror surface 12. As the high power laser beam 6 oscillated outside from the concave mirror 9 does not enter the beam detector 7, a detection signal outputted from the beam detector 7 is not saturated and the beam detector 7 is not damaged. Further, the positions of both mirrors 9 and 11 can be adjusted while the laser beam 6 is oscillated.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an unstable laser resonator.

[0002]

2. Description of the Related Art FIG. 3 shows an example of an off-axes type unstable laser resonator. The off-axes type unstable laser resonator includes a concave mirror 2 having a concave mirror surface 1 asymmetric with respect to a central axis. A convex mirror 4 having a convex mirror surface 3 smaller than the mirror surface 1 of the concave mirror 2 and asymmetric with respect to the central axis.
Are arranged so that the two mirror surfaces 1 and 3 face each other and the laser beam 6 generated by resonating the light 5 with the both mirror surfaces 1 and 3 passes outside the mirror surface 3 and is oscillated toward the outside. Have a configuration.

In the off-axes unstable laser resonator having the above-mentioned structure, in order to stabilize the laser beam 6, the optical axis position and output of the laser beam 6 oscillated from the concave mirror 2 to the outside of the resonator are set. The detection is performed by the beam detector 7, and the mutual positional relationship between the concave mirror 2 and the convex mirror 4 is adjusted based on the detection result to correct the optical axis fluctuation and the output change of the laser beam 6.

[0004]

However, when the output of the laser beam 6 oscillated from the concave mirror 2 to the outside of the resonator is high, the detection signal output from the beam detector 7 becomes saturated and the laser beam is saturated. The optical axis position and output of the beam 6 may not be accurately grasped, or the beam detector 7 may be damaged.

When detecting the optical axis position and output of the laser beam 6, a beam detector 7 must be installed in the optical path of the laser beam 6, and the optical axis position and output of the laser beam 6 are detected. However, the laser beam 6 cannot be used.

It is an object of the present invention to easily grasp the mutual positional relationship between a concave mirror and a convex mirror in an unstable laser resonator that oscillates a high-power laser beam without causing damage to the beam detector. I am trying.

[0007]

In order to achieve the above object, in the unstable laser resonator of the present invention, the concave mirror and the convex mirror having a mirror surface smaller than the mirror surface of the concave mirror face each other. In the unstable laser resonator arranged, a concave detection mirror portion is provided on one of the two mirrors, and a convex detection mirror portion is provided on the other, integrally with each mirror. A resonator is formed, and a beam detector is provided so that the laser beam for detection emitted from the unstable resonator for detection enters.

[0008]

When light is generated between the concave mirror and the convex mirror, a high-power laser beam generated by the resonance of the light by the mirror surfaces of both mirrors is oscillated outward from the mirror surface, and at the same time, the light is emitted. A low-output laser beam generated by resonating with the mirror surfaces of the concave detection mirror portion and the convex detection mirror portion is incident on the beam detector.

At this time, the output of the beam detector is detected and the relative positional relationship between the two mirrors is adjusted based on the detected value.
A high-power laser beam is oscillated in a stable state from the mirror surface to the outside.

In the present invention, since the laser beam generated by the resonance of light by the concave mirror and the convex mirror does not enter the beam detector, the detection signal output from the beam detector becomes saturated, The beam detector is not damaged.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of an unstable laser resonator according to the present invention. In the figure, the same reference numerals as those in FIG. 3 represent the same parts.

Reference numeral 9 is a concave mirror, and 11 is a convex mirror. The mirror surfaces 8 and 10 of both mirrors 9 and 11 are asymmetric with respect to the center line, and the mirror surface 10 of the convex mirror 11 is formed smaller than the mirror surface 8 of the concave mirror 9. Has been done.

In both mirrors 9 and 11, a laser beam 6 generated by both mirror surfaces 8 and 10 facing each other and resonating the light 5 by both mirror surfaces 8 and 10 passes outside the mirror surface 10 and is directed to the outside. It is arranged to oscillate.

Reference numeral 13 denotes a concave detection mirror portion, and the concave detection mirror portion 13 is integrally provided on the concave mirror 9 so as to be located on the side substantially opposite to the laser beam emitting portion of the concave mirror 9. ing.

Reference numeral 15 denotes a convex detecting mirror portion, and the convex detecting mirror portion 15 is provided integrally with the convex mirror 11 so as to face the concave detecting mirror portion 13 described above.

Reference numeral 16 is a HeNe laser oscillator.
The eNe laser oscillator 16 is arranged on the back surface of the concave mirror 9, and the low-power HeNe laser beam 22 oscillated by the HeNe laser oscillator 16 is detected as a convex surface through a beam emission hole 18 formed in the concave mirror 9. The light is incident on the mirror surface 14 of the mirror section 15.

The mirror surface 12 of the concave detection mirror portion 13 described above.
Is formed in a concave shape continuous with the mirror surface 8 of the concave mirror 9, and the mirror surface 14 of the convex detecting mirror portion 15 is formed in a convex shape continuous with the mirror surface 10 of the convex mirror 11 and both detections are performed. An unstable resonator 21 for detection is configured by the mirror units 13 and 15.

The concave mirror 9 and the convex mirror 11 having the above structure
When the light 5 is generated by both mirrors 9 and 11, a high-power laser beam 6 is generated by the mirror surfaces 8 and 10 and a low-power laser beam 17 is generated by the mirror surfaces 12 and 14.

Further, a beam detector 7 is arranged on the rear side of the convex mirror 11, and the laser beam 17 for detection emitted from the above-mentioned mirror surface 12 to the outside is arranged on the beam detector 7. Is incident.

The concave mirror 9 and the convex mirror 11 are provided with position adjusting devices 19 and 20, respectively.

The operation of this embodiment will be described below.

In order to operate the unstable laser resonator shown in FIG. 1, the HeNe laser oscillator 16 and the HeNe are previously operated.
By oscillating the laser beam 22, the relative positional relationship between the two mirrors 9 and 11 forming the unstable resonator 21 for detection is adjusted.

Next, when light 5 is generated between the two mirrors 9 and 11, a high-power laser beam 6 generated by the light 5 resonating with the mirror surfaces 8 and 10 of the two mirrors 9 and 11 is a mirror surface 8. From the mirror surface 1 to the outside, and at the same time, a low-power laser beam 17 generated by the light 5 resonating with the mirror surfaces 12 and 14 of both mirrors 9 and 11 is generated.
It is incident on the beam detector 7 from 2.

At this time, the output of the beam detector 7 is detected, and the relative positional relationship between the two mirrors 9 and 11 is adjusted based on the detected value, so that the high-power laser beam 6 is directed outward from the mirror surface 8. Try to oscillate in a stable state.

As described above, in this embodiment, since the laser beam 6 oscillated to the outside from the concave mirror 9 does not enter the beam detector 7, the detection signal output from the beam detector 7 is saturated. The position of both mirrors 9 and 11 can be adjusted even when the beam detector 7 is not damaged and the laser beam 6 is oscillating.

FIG. 2 shows another embodiment of the unstable laser resonator according to the present invention. In the figure, the same reference numerals as those in FIG. 1 represent the same parts.

In the present embodiment, the concave detection mirror portion 13 and the convex detection mirror portion 15 are shaped so that the detection laser beam 17 is resonated by the mirror surfaces 12 and 14, and the detection laser beam 17 is the mirror surface 12. It is formed so as to pass through the outside of and to be ejected to the outside.

In the present embodiment having such a configuration, the same operational effect as that shown in FIG. 1 described above can be obtained, and in the present embodiment, the HeNe laser oscillator 16 and the beam detector 7 are provided. Are arranged on the back side of the concave mirror 9, so that the HeNe laser oscillator 16 and the beam detector 7 can be mounted on the same mount.

The unstable laser resonator of the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention.

[0031]

As described above, in the unstable laser resonator of the present invention, the laser beam generated by the resonance of the light by the concave mirror and the convex mirror does not enter the beam detector. It is said that the detection signal output from the detector will not be saturated, the beam detector will not be damaged, and the position of the concave mirror and the convex mirror can be adjusted even when the laser beam is oscillating. It can exert an excellent effect.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing an embodiment of an unstable laser resonator of the present invention.

FIG. 2 is a conceptual diagram showing another embodiment of the unstable laser resonator of the present invention.

FIG. 3 is a conceptual diagram showing an example of a conventional unstable laser resonator.

[Explanation of symbols]

 7 Beam Detector 8, 10, 12, 14 Mirror Surface 9 Concave Mirror 11 Convex Mirror 13 Concave Detection Mirror 15 Convex Detection Mirror 17 Detection Laser Beam 21 Unstable Resonator for Detection

Claims (1)

[Claims] 1. An unstable laser resonator in which a concave mirror and a convex mirror having a mirror surface smaller than that of the concave mirror are arranged so that both mirror surfaces face each other, and a concave detecting mirror portion is provided on one of the both mirrors. On the other hand, a convex detecting mirror portion is integrally provided for each mirror to form an unstable resonator for detection, and the detecting laser beam oscillated by the unstable resonator for detection. An unstable laser resonator, characterized in that a beam detector is provided so as to inject light.