JPH05183219A - Laser oscillator - Google Patents

Abstract

PURPOSE:To obtain a laser oscillator which can generate laser light having excellent pointing (positional accuracy) stability. CONSTITUTION:The angle adjusting mechanism of an adjusting plate 40 is constituted of one fulcrum member 50 which decides the relative position between an optical substrate 38 and the plate 40, two angle adjusting screws 46, and three springs 55 so that the three springs 55 can be fitted in corresponding to the member 50 and screws 46, respectively. Therefore, the angle of the plate 40 can be stabilized by preventing the occurrence of an angle changing phenomenon on the plate 40.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to stabilization of pointing (positional accuracy) of a laser oscillator.

[0002]

2. Description of the Related Art FIG. 5 shows, for example, JP-A-60-25468.
4 is a perspective view showing a configuration of a conventional laser oscillator disclosed in Japanese Patent Publication No. 4), FIG. 6 is a cross-sectional view showing a configuration of one laser light reflecting means in the conventional laser oscillator, and FIG. FIG. 8 is an explanatory view showing an angle adjusting mechanism, FIG. 8 is a detailed view showing a main part of an angle adjusting mechanism of an adjusting plate in a conventional laser oscillator, and FIG. 9 is a vertical cross section of an oscillator including a resonator optical path in a conventional laser oscillator in a longitudinal direction. FIG. 10 is a perspective view showing a spring used in the angle adjusting mechanism of the adjusting plate in the conventional laser oscillator. Figure 7
In the angle adjusting mechanism of the adjusting plate shown in FIG.
Shows a plan view, and FIG. 7B shows a sectional view.

In the laser oscillator shown in FIG. 5, 1
Reference numeral 0 is a housing for enclosing a laser medium gas, 4 is a pair of discharge electrodes, 8 is a heat exchanger, 6 is a blower (blower), 32 is a partial reflection mirror, 26, 28 and 30 are total reflection mirrors, and 12a is a partial reflection mirror. Laser light reflecting means including a mirror 32 and a total reflection mirror 28, 1
Reference numeral 2b is a laser beam reflecting means including a total reflection mirror 30 and a total reflection mirror 26, and 2 is a laser beam. In the laser beam reflecting means 12a shown in FIG. 6, 14 and 15 are apertures respectively arranged immediately before the partial reflecting mirror 32 and the total reflecting mirror 28, 36 is an optical base for holding the laser beam reflecting means 12a, 44 Is a connecting rod for connecting the optical base 36 and an optical base (not shown) of the laser light reflecting means 12b, 54 is a bellows mounted so as to hold a vacuum seal between the housing 10 and the optical base 36, 38 Is an optical substrate attached to the optical base 36. 42 and 40 are respectively attached with the partial reflection mirror 32 and the total reflection mirror 28, and the partial reflection mirror 3
2 is an adjustment plate for adjusting the angles of 2 and the total reflection mirror 28.

In the angle adjusting mechanism of the adjusting plate 40 attached to the optical substrate 38 shown in FIG. 7, 46 is an angle adjusting screw for adjusting the angle of the adjusting plate 40, and 47 is the optical substrate 38 and the angle adjusting screw 46. 4 screwed together
8 is an O-ring for rotating the angle adjusting screw 46 while vacuum-sealing, 49 is a receiving member provided on the adjusting plate 40 with which the tip end of the angle adjusting screw 46 abuts, 55 is the optical plate for the adjusting plate 40. A spring arranged in an elastically biased state so as to be attracted to 38, 50 a fulcrum member provided on the adjusting plate 40, 56 cooling water flowing through the adjusting plate 40, 58 tubes for flowing the cooling water 56, 51a and 51b A hole provided in the optical substrate 38 for flowing the cooling water 56, and 52 are joints for connecting the tube 58 to the optical substrate 38 and the adjusting plate 40.

In the structure of the main part of the angle adjusting mechanism of the adjusting plate 40 shown in FIG. 8, 60 is a spring rod screwed into the optical substrate 38, 62 is a contact portion between the spring rod 60 and the spring 55, and 63 is the adjusting plate 40. The contact portion of the spring 55.
Further, 46 is an angle adjusting screw, 47 is a screw portion, 49 is a receiving member, and 50 is a fulcrum member.

In the schematic diagram of the laser oscillator shown in FIG. 9, 18 is an excitation region in which the laser medium gas is in an excited state due to the discharge between the pair of discharge electrodes 4 in the housing 10, and 20, 22, 24 are A first optical axis, a second optical axis, and a third optical path that are three resonator optical paths that draw a Z shape passing through the excitation region 18.
Is the optical axis of. Further, 2 is laser light, 12a is laser light reflecting means including a partial reflection mirror 32 and a total reflection mirror 28, and 12b.
Is a laser beam reflecting means including a total reflection mirror 30 and a total reflection mirror 26. In the spring 55 shown in FIG. 10, 62,
Reference numeral 63 is a contact portion where the spring 55 comes into contact with other components.

Next, the operation of the above conventional laser oscillator will be described. The laser medium gas in the housing 10 shown in FIG. 5 passes between the pair of discharge electrodes 4 and is excited into a state in which laser oscillation is possible, and then enters the heat exchanger 8 and is cooled and then blower 6 is discharged. It circulates in the direction indicated by arrow A in FIG.

As shown in FIG. 9, the partial reflection mirror 32 and the total reflection mirrors 26, 2 arranged in the longitudinal direction of the housing 10.
8 and 30, the first optical axis 20 and the second optical axis 20 which are three resonator optical paths that draw a Z-shape passing through the excitation region 18 in which the laser medium gas is excited by the discharge between the pair of discharge electrodes 4. The optical axis 22 and the third optical axis 24 are determined. The laser light 2 reflected by the total reflection mirror 26 reaches the total reflection mirror 28 through the first optical axis 20. Since the total reflection mirror 28 is tilted slightly downward, the laser light 2 is reflected by the first optical axis 20.
The total reflection mirror 30 is reached through the second optical axis 22 which is inclined slightly downward. Since the total reflection mirror 30 is tilted slightly upward, the laser light 2 reaches the partial reflection mirror 32 through the third optical axis 24 parallel to the first optical axis 20.
A part of the laser light 2 that reaches the partial reflection mirror 32 is output as it is to the outside, and the remaining laser light 2 returns to the total reflection mirror 26 through a route opposite to the above, and the above process is repeated. The laser light 2 is amplified while repeatedly passing through the excitation region 18 and output from the partial reflecting mirror 32 to the outside.

Next, the angle adjusting mechanism of the total reflection mirror 28 shown in FIG. 7 will be described. The total reflection mirror 28 is an adjusting plate 40.
The angle of the total reflection mirror 28 is adjusted by adjusting the angle of the adjusting plate 40. As shown in FIG. 8, the spring 55 is inserted in a compressed state between the adjusting plate 40 and the spring rod 60 screwed into the optical substrate 38. Therefore, the adjusting plate 40 is elastically biased by the spring 55 so as to be attracted to the optical substrate 38 by the restoring force of the spring 55. Since the adjusting plate 40 and the optical substrate 38 are in a state of being stretched with each other by the fulcrum member 50 and the two angle adjusting screws 46, the relative length of the fulcrum member 50 and the protruding length of the angle adjusting screw 46 from the optical substrate 38 are relative to each other. The angle of the adjusting plate 40 is determined by the relationship. By rotating the angle adjusting screw 46, it is possible to change the protruding length of the angle adjusting screw 46 from the optical substrate 38 and adjust the angle of the adjusting plate 40 vertically and horizontally.

Since the total reflection mirror 28 has a certain absorptivity for the laser light 2, the total reflection mirror 28 generates heat when the laser light 2 is irradiated. Therefore, the total reflection mirror 28 indirectly cools the adjustment plate 40 by cooling it with the cooling water 56. The cooling water 56 passes from the outside through the tube 58, through the hole 51a of the optical substrate 38, and then through the inside of the adjusting plate 40 and again through the hole 51b of the optical substrate 38 to the outside.

Generally, the springs 55 are provided at two positions with respect to the fulcrum member 50 and the two angle adjusting screws 46, as shown in FIG. 7 (a). At this position, the center of the resultant force of the attraction forces by the two springs 55 is inside the triangle formed by the fulcrum member 50 and the two angle adjusting screws 46. This means that when the angle adjusting screws 46 are adjusted, the angle This is to prevent the adjusting screw 46 and the receiving member 49 from floating, and is normally configured in this way, and the adjusting plate 42 of the partial reflecting mirror 32 is also configured in the same manner.

Since the adjusting plate 42 of the partial reflecting mirror 32 is in a vacuum state in the housing 10, the center of the partial reflecting mirror 32 is set to the center of gravity by the pressure difference between the atmospheric pressure and the vacuum pressure in addition to the attractive force of the spring 55. Since the force is strongly attracted to the optical substrate 38 side, the adjusting plate 42 is very stably attracted and attached to the optical substrate 38. However, the total reflection mirror 2
Since the adjusting plate 40 of No. 8 is in the vacuum inside the housing 10, the attracting force due to the vacuum like the adjusting plate 42 cannot be expected, so that it is attracted to the optical substrate 38 by the attracting force of only the two springs 55. Therefore, the adjustment plate 40 in vacuum becomes unstable as compared with the adjustment plate 42 in contact with the atmosphere.

That is, for example, as shown in FIG. 7A, the distance C from the fulcrum member 50 to the spring 55 is long, and the distance B from the angle adjusting screw 46 to the spring 55 is short. Although the fulcrum member 50 is pressed against the adjusting plate 40 with a large torque, on the contrary, the fulcrum member 50 is pressed against the optical substrate 38 only with a small torque. Therefore, the adjusting plate 40 in the vacuum is unstable with respect to the force of the fulcrum member 50 to lift the fulcrum.

By the way, as shown in FIG. 7B, a tube 58 for flowing the cooling water 56 is connected to the adjusting plate 40. The tube 58 itself has an elastic force, and the elastic force of the tube 58 changes due to the temperature change and pressure change of the cooling water 56 flowing through the tube 58. Furthermore, the elastic force of the tube 58 also varies depending on the piping method such as the length and bending radius of the tube 58. Therefore, depending on the object or in some circumstances, the elastic force of the tube 58 may act to lift the fulcrum of the fulcrum member 50, which may change the angle of the adjusting plate 40. When the angle of the adjusting plate 40 changes in this way, the angle of the total reflection mirror 28 changes, the optical axis of the laser light 2 in the resonator is deviated, and the stability of the pointing (positional accuracy) of the laser light 2 deteriorates. Will be humiliated.

As shown in FIG. 10, the spring 55 has a coil shape, and is usually a right-handed coil spring. Reference numeral 62 denotes a contact portion between the spring rod 60 and the spring 55, and 6
Reference numeral 3 denotes a contact portion between the adjusting plate 40 and the spring 55. Here, if the temperature of the spring 55 changes, the total length of the coil changes. For example, if the temperature of the spring 55 rises, the contact portions 62 and 63 of the spring 55 tend to extend in the directions indicated by arrows D and E in FIG. 10, respectively. At the contact portions 62 and 63,
Between the spring rod 60 and the spring 55, between the adjusting plate 40 and the spring 55
A frictional force acts between them and a torsion torque acts between the spring rod 60 and the adjusting plate 40. As a result, when the spring 55 is right-handed, a clockwise torque is generated between the adjusting plate 40 and the optical substrate 38, and this torque is generated between the fulcrum member 50 and the optical substrate 38 by the attractive force, and between the receiving member 49. When the frictional force between the angle adjusting screws 46 becomes larger, the adjusting plate 40 rotates with respect to the optical substrate 38, which causes the angle of the adjusting plate 40 to change. Then, when the angle of the adjusting plate 40 changes, the angle of the total reflection mirror 28 changes and the optical axis of the laser light 2 in the resonator is deviated, and the stability of the pointing (positional accuracy) of the laser light 2 is impaired. Will be seen.

[0016]

Since the conventional laser oscillator described above is constructed as described above, the tube 5
There is a problem that the stability of the pointing (positional accuracy) of the laser light 2 may be deteriorated due to a temperature change or pressure change of the cooling water 56 flowing in 8 or a variation at the time of assembling the tube 58. It was

The present invention has been made to solve the above problems, and an object thereof is to obtain a laser oscillator having excellent stability of pointing (positional accuracy) of laser light.

[0018]

A laser oscillator according to a first aspect of the present invention has a plurality of resonator mirrors forming a resonator, and at least one of the resonator mirrors is arranged in a vacuum, In an apparatus having an adjusting plate for adjusting the angle of the resonator mirror arranged in this vacuum, and an optical substrate formed by attaching the adjusting plate to shut off the vacuum, an angle adjusting mechanism of the adjusting plate is It is composed of one fulcrum member that determines the relative position of the board and the adjusting plate, two angle adjusting screws and three springs, and these three springs are attached corresponding to one fulcrum member and two angle adjusting screws, respectively. It is configured as follows.

The laser oscillator according to the second invention is
A plurality of resonator mirrors that form a resonator, an adjusting plate for adjusting the angle of the resonator mirror, and an optical substrate to which the adjusting plate is attached are provided. Composed of one fulcrum member that determines the relative position of the optical board and the adjusting plate, two angle adjusting screws and three springs, and a contact portion between this spring and the adjusting plate or a part fixed to this adjusting plate, or A member for reducing friction of the contact portion is inserted into at least one contact portion of the spring and the optical substrate or a contact portion of a component fixed to the optical substrate.

The laser oscillator according to the third invention is
A plurality of resonator mirrors that form a resonator, an adjusting plate for adjusting the angle of the resonator mirror, and an optical substrate to which the adjusting plate is attached are provided. , A fulcrum member that determines the relative position of the optical board and the adjusting plate, two angle adjusting screws, and three springs. At least one of these three springs is a right-handed spring, and at least one is A left-handed spring, at least one of which is a right-handed or left-handed spring.

[0021]

The laser oscillator according to the first aspect of the present invention is an angle adjusting mechanism for an adjusting plate, which comprises one fulcrum member for determining the relative positions of the optical substrate and the adjusting plate, two angle adjusting screws, and three springs. The three springs that are attached to the fulcrum member and the two angle adjusting screws, respectively, prevent the fulcrum of the fulcrum member from floating from the optical substrate.

The laser oscillator according to the second aspect of the present invention includes one fulcrum member that determines the relative position of the optical substrate and the adjusting plate, and
An angle adjusting mechanism of an adjusting plate composed of one angle adjusting screw and three springs, a contact portion between the spring and the adjusting plate or a component fixed to the adjusting plate, or a spring and an optical substrate or a component fixed to this optical substrate. The member that reduces the friction of the contact portion inserted into at least one of the contact portions of
Even if the spring generates torque due to temperature change, the spring slides at the contact portion, and the torque is not transmitted to other parts.

The laser oscillator according to the third invention is
An angle adjusting mechanism for the adjusting plate, which is composed of one fulcrum member that determines the relative position of the optical substrate and the adjusting plate, two angle adjusting screws, and three springs, and is configured by using right-handed springs and left-handed springs. The three springs cancel the torque as described above because the direction of the torque generated by the temperature change is reversed between the right-handed spring and the left-handed spring.

[0024]

EXAMPLES Example 1. Embodiments of the present invention will be described below with reference to the drawings. FIG. 5 is a perspective view showing the configuration of the conventional laser oscillator, FIG. 6 is a cross-sectional view showing the configuration of one laser beam reflecting means in the conventional laser oscillator, and FIG. 9 shows an oscillator including a resonator optical path in the conventional laser oscillator. The schematic view showing the vertical cross section in the longitudinal direction is the same as that of the embodiment of the present invention, and the description thereof is omitted here.

FIG. 1 is an explanatory view showing an angle adjusting mechanism of an adjusting plate in a laser oscillator which is an embodiment of the first invention.
1A is a plan view and FIG. 1B is a sectional view.
The same reference numerals as those in FIG. 7 indicate the same or corresponding portions, and detailed description thereof will be omitted. The laser oscillator according to the first embodiment of the present invention shown in FIG. 1 is different from the conventional laser oscillator shown in FIG. 7 in that the number of springs 55 is two to three, and one of them is one spring 55. That is, it is arranged in the vicinity of the fulcrum member 50.

In the laser oscillator according to the first embodiment of the present invention, since the spring 55 is attached near either of the fulcrum member 50 and the two angle adjusting screws 46, the fulcrum member 50 is provided. The optical substrate 38, the angle adjusting screw 46 and the receiving member 49 can be pressed by a substantially uniform force. Therefore, in particular, since the lifting of the fulcrum by the fulcrum member 50 can be prevented, a temperature change or a pressure change of the cooling water 56 or the like, which is a problem in the above-described conventional laser oscillator, or a variation at the time of assembling the pipe of the tube 58. It is possible to prevent the phenomenon in which the angle of the adjusting plate 40 changes due to such reasons.

Example 2. FIG. 2 is a detailed view showing a main part of an angle adjusting mechanism of an adjusting plate in a laser oscillator which is an embodiment of the second invention. The same reference numerals as those in FIG. 8 indicate the same or corresponding parts, and the detailed description thereof Is omitted. 2 is different from the conventional laser oscillator shown in FIG. 8 in that the thrust bearing 64 is inserted between the adjusting plate 40 and the contact portion 63 of the spring 55. That is, the spring 55 is configured so that the rotation in the circumferential direction can freely move at the contact portion 63 between the adjusting plate 40 and the spring 55. Therefore, even if the temperature of the spring 55 rises, the contact portion 63 of the spring 55 has a very small frictional force, so that the torsional torque generated between the spring rod 60 and the adjusting plate 40 is also very small, and this torsional torque is , Between the fulcrum member 50 and the optical substrate 38 by the attraction force of the spring 55, and between the receiving member 49 and the angle adjusting screw 4.
The frictional force between the adjusting plates 40 does not become larger than the frictional force between the adjusting plates 40. Therefore, the angle of the adjusting plate 40 can be stabilized without rotating the adjusting plate 40 with respect to the optical substrate 38.

In the embodiment of the second invention, the thrust bearing 6 is provided between the adjusting plate 40 and the contact portion 63 of the spring 55.
4 has been described, the thrust bearing 64 may be inserted between the spring rod 60 and the contact portion 62 of the spring 55. Of course, both contact portions 62 and 63 of the spring 55 have thrust bearings. A configuration in which 64 is inserted may be adopted, and the same effect as that of the second embodiment of the present invention can be obtained.

Further, in the embodiment of the second invention, the adjusting plate 4 is used.
0 and the contact portion 63 of the spring 55 between the thrust bearing 64
In the above description, the component inserted into the contact portion 63 of the spring 55 may be any member that reduces the friction of the contact portion 63, such as a hard metal or a synthetic resin such as Teflon. A washer made of a material may be used, and the same effect as that of the embodiment of the second invention can be obtained.

Example 3. 3A and 3B are explanatory views showing an angle adjusting mechanism of an adjusting plate in a laser oscillator which is an embodiment of the third invention, FIG. 3A is a plan view, and FIG. 3B is a sectional view. The same reference numerals as 7 denote the same or corresponding portions, and detailed description thereof will be omitted. The configuration of the laser oscillator according to the third embodiment of the invention shown in FIG. 3 is different from that of the conventional laser oscillator shown in FIG.
One is right-handed spring 55a and one is left-handed spring 5
5b, and each winding direction is different. Therefore, even when the temperature of the spring 55 rises, the torques generated in the right-handed spring 55a and the left-handed spring 55b are in opposite directions, canceling each other out, and the adjusting plate 40 rotates with respect to the optical substrate 38. Therefore, the angle of the adjusting plate 40 can be stabilized for that reason.

In the embodiment of the third aspect of the invention, two springs 55 are a right-handed spring 55a and a left-handed spring 55.
Although the configuration in which b is arranged separately has been described, as shown in the detailed view showing the main part of the angle adjusting mechanism of the adjusting plate in the laser oscillator which is another embodiment of the third invention of FIG. Right-handed spring 55 with different winding directions
The a and the left-handed spring 55b may have a structure in which their respective ends are overlapped with each other, and the same effect as that of the above-described third embodiment of the invention is obtained.

[0032]

As described above, according to the laser oscillator of the first aspect of the invention, the angle adjusting mechanism of the adjusting plate has one fulcrum member and two angle adjusting screws for determining the relative position between the optical substrate and the adjusting plate. And 3 springs, and these 3 springs
Since the fulcrum member and the two angle adjusting screws are attached to correspond to each other, it is possible to provide a laser oscillator having excellent stability of pointing (positional accuracy) of laser light.

According to the laser oscillator of the second invention,
The angle adjusting mechanism of the adjusting plate is configured by one fulcrum member that determines the relative position between the optical substrate and the adjusting plate, two angle adjusting screws, and three springs, and this spring, the adjusting plate, or a component fixed to this adjusting plate. Since the contact portion of, or at least one of the contact portion of the spring and the optical substrate or the component fixed to the optical substrate, the member for reducing the friction of the contact portion is inserted, It is possible to provide a laser oscillator having excellent stability of pointing (positional accuracy) of laser light.

According to the laser oscillator of the third invention,
The angle adjusting mechanism of the adjusting plate is configured by one fulcrum member that determines the relative position of the optical substrate and the adjusting plate, two angle adjusting screws, and three springs, and these three springs are at least 1
One is a right-handed spring, at least one is a left-handed spring, and at least one is a right-handed or left-handed spring, so a laser oscillator with excellent stability of laser light pointing (positional accuracy) is provided. There is an effect that can be done.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an angle adjusting mechanism of an adjusting plate in a laser oscillator which is an embodiment of the first invention.

FIG. 2 is a detailed view showing a main part of an angle adjusting mechanism of an adjusting plate in a laser oscillator that is an embodiment of the second invention.

FIG. 3 is an explanatory view showing an angle adjusting mechanism of an adjusting plate in a laser oscillator which is an embodiment of the third invention.

FIG. 4 is a detailed view showing a main part of an angle adjusting mechanism of an adjusting plate in a laser oscillator according to another embodiment of the third invention.

FIG. 5 is a perspective view showing a configuration of a conventional laser oscillator.

FIG. 6 is a cross-sectional view showing a configuration of one laser light reflecting means in a conventional laser oscillator.

FIG. 7 is an explanatory view showing an angle adjusting mechanism of an adjusting plate in a conventional laser oscillator.

FIG. 8 is a detailed view showing a main part of an angle adjusting mechanism of an adjusting plate in a conventional laser oscillator.

FIG. 9 is a schematic view showing a vertical cross section in a longitudinal direction of an oscillator including a resonator optical path in a conventional laser oscillator.

FIG. 10 is a perspective view showing a spring used in an angle adjusting mechanism of an adjusting plate in a conventional laser oscillator.

[Explanation of symbols]

 2 Laser Light 4 Discharge Electrode 6 Blower (Blower) 8 Heat Exchanger 10 Housing 12a Laser Light Reflecting Means 12b Laser Light Reflecting Means 14 Aperture 15 Aperture 18 Excitation Area 20 First Optical Axis 22 Second Optical Axis 24 Third Optical axis 26 Total reflection mirror 28 Total reflection mirror 30 Total reflection mirror 32 Partial reflection mirror 36 Optical base 38 Optical substrate 40 Adjustment plate 42 Adjustment plate 44 Connecting rod 46 Angle adjustment screw 47 Screw portion 48 O-ring 49 Receiving member 50 Support point member 51a hole 51b hole 52 joint 54 bellows 55 spring 55a spring 55a spring 55b spring 56 cooling water 58 tube 60 spring rod 62 contact part 63 contact part 64 thrust bearing

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[Procedure amendment]

[Submission date] June 4, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Claims

[Correction method] Change

[Correction content]

[Claims]

Claims (3)

[Claims] 1. A housing, an optical base mounted on the housing to maintain a vacuum inside the housing, an adjusting plate mounted on the optical base and arranged inside the housing, and fixed to the adjusting plate. And the first and second angle adjusting screws for adjusting the angle of the adjusting plate with respect to the optical base, and the first fulcrum member. A laser oscillator comprising: angle adjusting means; and first to third springs provided respectively corresponding to the first and second angle adjusting screws and the first fulcrum member. 2. A housing, an optical base mounted on the housing to maintain a vacuum inside the housing, an adjusting plate mounted on the optical base and disposed inside the housing, and fixed to the adjusting plate. And the first and second angle adjusting screws for adjusting the angle of the adjusting plate with respect to the optical base, and the first fulcrum member. Angle adjusting means, first to third springs provided corresponding to the first and second angle adjusting screws and the first fulcrum member, respectively, and provided at one end of the spring and contacting the spring. A laser oscillator comprising: a member that reduces friction between the members. 3. A housing, an optical base mounted on the housing to maintain a vacuum inside the housing, an adjusting plate mounted on the optical base and arranged inside the housing, and fixed to the adjusting plate. And the first and second angle adjusting screws for adjusting the angle of the adjusting plate with respect to the optical base, and the first fulcrum member. Angle adjusting means, a right-handed first spring, a left-handed second spring, and a right-handed or left-handed first spring, which are provided corresponding to the first and second angle adjusting screws and the first fulcrum member, respectively. A laser oscillator comprising: