JP2001326403A - Orthogonal excitation-type laser oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an orthogonal excitation-type laser oscillator in which an optical base is hardly influenced by the deformation due to heat or the like of an oscillator enclosure and which can enhance the time-dependent stability in the outgoing direction of a laser beam. SOLUTION: The orthogonal excitation-type laser oscillator comprises the oscillator enclosure 1. The oscillator comprises a rear-part optical base 7 which is installed or the outside of the oscillator enclosure 1 and which has a total reflector 6. The oscillator comprises a front-part optical base 9 which faces the optical base 7 via the oscillator enclosure 1 and which comprises a partial reflector 8 constituting a resonator together with the total reflector 6. The oscillator comprises a support rod 13 and a support rod 14 which are constituted on the outside surface of the oscillator enclosure 1 and which support the base 7 and the base 9. The oscillator comprises a bracket 20 which is installed in the central part in the construction direction on the outside surface and which holds and fixes the support rod 13. The oscillator comprises a slide base 21b which is fixed to the central part in the construction direction on the outside surface. The oscillator comprises a holding bracket 21a which is coupled to the slide base' 21b and which holds the support rod 14. A bracket by which the bracket part 21a and the slide base 21b are relatively moved with reference to the displacement of the outside surface in a direction perpendicular to the construction direction is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a quadrature pump laser oscillator, and more particularly to a support structure of an optical base constituting an optical resonator of the quadrature pump laser oscillator.

[0002]

2. Description of the Related Art FIGS.
An example of a conventional quadrature excitation laser oscillator disclosed in Japanese Patent Application Laid-Open No. 8-18883 and Japanese Patent Application Laid-Open No. 7-307506 will be described. This orthogonal excitation type laser oscillator has an oscillator housing 1 having a hermetically sealed structure in which a laser medium gas such as CO ₂ gas is sealed. In the oscillator housing 1, discharge electrodes 2a and 2b for generating a laser beam and a laser are provided. A heat exchanger 3 for cooling the medium gas, a blower 4 for circulating the laser medium gas,
A duct 5 is provided for returning the laser medium gas passing between the discharge electrodes 2a and 2b to the heat exchanger 3.

On both sides of the oscillator housing 1 in the optical axis direction, a rear optical base 7 holding a total reflection mirror 6 and a front optical base holding a partial reflection mirror 8 on the same optical axis as the total reflection mirror 6 are provided. The table 9 is arranged in parallel with each other, and the total reflection mirror 6 and the partial reflection mirror 8
Constitute an optical resonator.

The oscillator housing 1 and the rear optical base 7 are connected to each other, and the oscillator housing 1 and the front optical base 9 are connected by a bellows 10 and 11 at a laser beam passing portion.
The rear optical base 7 and the front optical base 9 are firmly connected to each other by a total of three support rods 12, 13, and 14, two upper and one lower. The support rods 12, 13, 14
It extends through the end plates 15 and 16 on both sides of the oscillator housing 1 and extends in the optical axis direction.

In this orthogonally pumped laser oscillator, the laser medium gas, which has become hot due to the discharge of the laser generating portion by the discharge electrodes 2a and 2b, reaches the heat exchanger 3 through the duct 5 and passes through the heat exchanger 3. The cooled laser medium gas is conveyed to the blower 4 and is again sent to the laser generator by the discharge electrodes 2a and 2b. The flow of the laser medium gas is indicated by an arrow A in FIGS.

Although the lower support rod 12 only penetrates the end plates 15 and 16 and is not fixed to the oscillator housing 1,
Gas flow upstream (discharge electrodes 2a,
The support rod 13 on the side before passing through 2 b) is connected to the end plate 16, that is, the end face of the beam exit side of the oscillator housing 1 by a spherical joint type connecting member 18 so as to be tiltable in all directions. 15, that is, a spherical joint type connecting member 18 fixed on a connecting member 19 slidable in the axial direction of the support rod 13, that is, in the X-axis direction in the drawing at the end surface of the oscillator housing 1 on the beam total reflection side. They are connected so as to be tiltable in all directions and movable in the X-axis direction. Further, the gas flow downstream (discharge electrode 2
The support rod 14 on the side after passing through the end plates 16 is restrained from moving in the X-axis direction by the connecting member 17 at the end plate 16, in a direction perpendicular to the axial direction of the support rod 14, that is, in the drawing. The end plate 15 is slidably connected in the Y-axis direction.
The connection member 17 is installed on the connection member 19 slidable in the X-axis and Y-axis directions.
They are connected so as to be movable in the axial direction and rotatable on the XY plane.

[0007] Further, a supporting rod for connecting the rear optical base and the front optical base is fixedly connected to the oscillator housing at the center in the optical axis direction of the oscillator housing in addition to both end portions of the oscillator housing. A supporting structure is disclosed in Japanese Patent Application Laid-Open No. 53-12568.
No. 3 discloses this.

[0008]

The flow of the laser medium gas inside the oscillator housing 1 of this orthogonally pumped laser oscillator is as described above. Therefore, the laser medium gas in the upper part of the oscillator housing 1 Before and after passing through the laser generating section, that is, the temperature differs between the gas flow upstream side and the gas flow downstream side, the laser medium gas temperature on the gas flow upstream side is low, and the laser medium gas temperature on the gas flow downstream side becomes high due to discharge. I have. When the temperature of the laser medium gas inside is transmitted to the oscillator housing 1 itself, a temperature distribution difference occurs in the oscillator housing 1. Oscillator housing 1
As shown in FIG. 14, thermal deformation occurs in a curved shape, and the support rods 13 and 14 are connected to the oscillator housing 1 at the longitudinal end of the oscillator housing 1 having a large absolute value of the amount of thermal deformation. Since they are connected, the support rods 13 and 14 and the optical bases 7 and 9 are deformed as shown in FIG. In FIG. 14, the dotted line shows the initial state, that is, the state before thermal deformation, and the solid line shows the state after thermal deformation. Even after the thermal deformation, the rear optical base 7 and the front optical base 9 maintain the parallel relationship, and are formed by the total reflection mirror 6 (not shown) and the partial reflection mirror 8 (not shown). Although the configuration of the optical resonator is maintained, its optical axis, that is, the traveling direction of the laser beam is shifted from the initially set direction.

That is, when the oscillator housing 1 undergoes thermal deformation, a total of four connection positions between the support rods 13 and 14 and the oscillator housing 1 are displaced, and accordingly, the rear optical base 7 and the front optical base are changed. The table 9 is tilted from the initial setting, the optical axis of the laser beam is shifted, and the traveling direction of the laser beam is shifted.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an optical base is hardly affected by deformation of an oscillator housing due to heat or the like, and a quadrature capable of improving the temporal stability of a laser beam emitting direction. This is to obtain an excitation type laser oscillator.

[0011]

According to the present invention, there is provided a quadrature excitation laser oscillator comprising: an oscillator housing; a first optical base provided outside the oscillator housing and having a first reflecting mirror;
A second optical base having the first optical base and a second reflecting mirror that is opposed to each other via the oscillator housing and constitutes the first reflecting mirror and the resonator; and on an outer surface of the oscillator housing. A first connecting member and a second connecting member that connect the first optical base and the second optical base and are provided at a central portion of the outer surface in the mounting direction, and A first support member for holding and fixing one connecting member, a mounting portion fixed to a center portion of the outer surface in the erection direction, and a movement holding for engaging the mounting portion and holding the second connecting member And a second support member with which the mounting portion and the movement holding portion relatively move with respect to the displacement of the outer surface in the direction perpendicular to the erection direction.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 A quadrature pump laser oscillator according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 7, the same or corresponding elements as those shown in the above-described conventional example are denoted by the same reference numerals as those in the above-described conventional example, and detailed description thereof will be omitted. In FIGS. 1 to 4, support rods 13 and 14 as connection members extending in the optical axis direction via the upper part of the oscillator housing 1 each have a bracket 20 at a substantially central portion in the axial direction (longitudinal direction). , 21 are connected to a substantially central portion of the upper surface of the oscillator housing 1 in the optical axis direction.

Of the two support rods 13, 14, the support rod 13 located on the side of the upper surface of the oscillator housing 1 where the amount of thermal deformation is small.
The central connection to the oscillator housing 1 is a completely fixed connection. On the other hand, the central connection of the support rod 14 on the side of the upper surface of the oscillator housing 1 where the amount of thermal deformation is large due to the high temperature of the laser medium gas to the oscillator housing 1 is a movable connection in which only the movement in the axial direction is restricted. ing.

As a specific configuration, the bracket 20 of the support rod 13 is fastened and fixed to the upper surface of the oscillator housing 1 by a bolt or the like (not shown) while being fixed to the support rod 13. The bracket 21 of the support rod 14 includes a holding bracket part 21a as a moving holding part and a slide base 21b as an attachment part, and is fixed to the upper surface of the oscillator housing 1 in a state where the holding bracket part 21a is fixed to the support rod 14. Is slidably engaged with the slide table 21b. The sliding direction of the bracket 21 is a direction orthogonal to the optical axis direction on a plane parallel to the upper surface of the oscillator housing 1, that is, the direction of the arrow B in FIG.

The sliding structure of the bracket 21 is as follows.
It is preferable to adopt a structure in which sliding is performed with low frictional resistance by a linear ball bearing or the like.

According to the above configuration, the position of the bracket 20 of the support bar 13 is set at a position where the amount of deformation of the oscillator housing 1 is relatively small, so that the amount of displacement of the support bar 13 is smaller than that of the related art. . In FIG. 4, the one shown by the dotted line shows the initial state, that is, the state before the thermal deformation, and the one shown by the solid line shows the state after the thermal deformation. As shown in FIG. 4, the position of the bracket 20 of the support rod 13 hardly changes before and after thermal deformation. The bracket 21 of the support rod 14 provided on the side of the upper surface of the oscillator housing 1 where the amount of thermal deformation is large is such that the holding bracket portion 21a and the slide base 21b are parallel to the optical axis direction in a plane parallel to the upper surface of the oscillator housing 1. It is possible to move relatively by sliding in an orthogonal direction. Therefore, as shown in FIG.
Since the support rod 14 does not follow the thermal deformation of the oscillator housing 1 and the shape of the support rod 14 is easy to maintain the shape before the thermal deformation of the oscillator housing 1, the deformation amount of the support rod 14 is reduced to the conventional amount. Compared to decrease.

As described above, the displacement of each of the support rods 13 and 14 is smaller than that of the conventional support rod, and as a result, they are connected to these support rods 13 and 14. The displacement amount of the optical bases 7 and 9 is also reduced as compared with the conventional one,
The deviation of the optical axis of the laser beam, that is, the amount of change in the laser beam position is reduced, and the temporal stability of the laser beam emission direction is improved.

The upper two support rods 13 and 14 are connected and supported at substantially the center of the oscillator housing 1 and at one or more other positions, in this embodiment, the oscillator housing 1 Is connected to a support 27 fixed to the side surface of the oscillator housing 1 with a degree of freedom in the in-plane direction of the upper surface of the oscillator housing 1.

FIG. 5 shows the oscillator housing 1 of the support rods 13 and 14.
It is sectional drawing of the support part in a side surface. These support rods 13 and 14
Is supported by an orthogonal movable base that can be displaced in two orthogonal directions by a spherical joint 23 and double slide bases 24 and 25. In this support structure, the connection support strength between the oscillator housing 1 and the support rods 13 and 14 is strong, and the oscillator can be displaced and rotated in two orthogonal directions other than the vertical direction, that is, the direction away from and away from the upper surface of the oscillator housing 1. Housing 1
The displacement in the in-plane direction of the upper surface, that is, the direction parallel to the surface is not transmitted to the support rods 13 and 14.

Further, as shown in FIG.
The support at the both end positions of the roller 14 may be a structure in which the rolling bearing 26 attached to the support rods 13 and 14 is installed on a slide table 25 which can move in the axial direction. Support is possible, and the cost is reduced due to the simple structure. Also in this support structure, the rolling bearing 26 and the slide table 25 can be displaced in two orthogonal directions.
6 is merely fixed on the slide table 25 and is not fixed, so that it can rotate freely and does not transmit the in-plane displacement of the upper surface of the oscillator housing 1 to the support bars 13 and 14.

The support fixed to the side surface of the oscillator housing 1 may be a V-shaped support 28 as shown in FIG. 7, and by adopting such a structure, the oscillator housing 1
Of the side surfaces, the temperature change is small, the influence of the thermal deformation of the oscillator housing 1 is hardly affected, and the oscillator housing 1 can be attached to the blower 4 side.
, The amount of displacement in the vertical direction is small, and it is more difficult to transmit the deformation of the oscillator housing 1 to the support rods 13 and 14.

The connection of the supporting rods 13 and 14 to the oscillator housing 1 in the vicinity of the ends is made by the thermal deformation of the oscillator housing 1.
This connection influences the deformation of the support rod 1, 14 in a form having a degree of freedom in the in-plane direction on the upper surface of the oscillator housing 1, that is, by the spherical joint movement by the spherical joint 23.
3 and 14 can be tilted and displaced in all directions in the plane with respect to the upper surface of the oscillator housing 1, and can be displaced in two orthogonal directions by the double slides 24 and 25, and slide on the upper surface of the oscillator housing 1 by sliding motion. On the other hand, the support rods 13 and 14 follow the thermal deformation of the oscillator housing 1 very little because they are attached so as to be displaceable in two orthogonal directions.
In Nos. 3 and 14, since the positional relationship between the oscillator housing 1 before the thermal deformation is easily maintained, the deformation amount is reduced as compared with the conventional one.

For this reason, the positions of the rear optical base 7 holding the total reflection mirror 6 and the front optical base 9 holding the partial reflection mirror 8 whose positional relationship is determined by the support rods 13 and 14. The relationship is also easy to maintain at the time of initial setting, that is, the positional relationship before the thermal deformation of the oscillator housing 1, and the deviation of the optical axis of the laser beam accompanying the thermal deformation of the oscillator housing 1 is reduced. Further, with the above-described configuration, the deviation of the optical axis of the laser beam is reduced,
Improving the connection support strength between the oscillator housing 1 and the support rods 13 and 14 is compromised.

The support 27 or the V-shaped support 28
Is attached to the side surface of the oscillator housing 1 with little temperature change, the amount of deformation of the support rods 13 and 14 is reduced, and the temporal stability of the laser beam is improved.

Embodiment 2 An optical base support structure of a quadrature excitation laser oscillator according to a second embodiment of the present invention will be described with reference to FIGS. 8 to 1
At 0, the same or corresponding components as those shown in FIGS. 1 to 7 are denoted by the same reference numerals as those in FIGS. 1 to 7, and detailed description thereof will be omitted.

In this embodiment, the two support rods 13 and 14 on the upper side of the oscillator housing 1 are respectively connected to the upper and lower sides of the oscillator housing 1 at a substantially central portion in a vertical direction, that is, in a direction in which the upper and lower surfaces of the oscillator housing 1 are separated from and contacted with each other. Are connected with a degree of freedom.

The bracket 30 of the support rod 13 is
The bracket 30 is fixed to the upper surface of the oscillator housing 1 via a vertical slide mechanism 32 that can move in the vertical direction such as a bearing such as a linear ball bearing while being fixed to the bracket 3.
Can slide vertically with respect to the upper surface of the oscillator housing 1. The bracket 31 of the support rod 14 is slidably engaged with a slide table 31b fixed to the upper surface of the oscillator housing 1 with the holding bracket portion 31a fixed to the support rod 14. At this time, the holding bracket portion 31a and the slide table 31b are engaged via the above-described vertical slide mechanism 32, and the sliding direction of the bracket 31 is orthogonal to the optical axis direction on a plane parallel to the upper surface of the oscillator housing 1. Direction and vertical direction.

According to the above configuration, the support rods 13, 14
The fixed point in the substantially central portion of the oscillator housing 1 can move in the vertical direction, while the center of the oscillator housing 1 is thermally deformed as shown in FIG. Even when the oscillators are deformed vertically as described above, the support bars 13 and 14 do not follow the thermal deformation of the oscillator housing 1, and the support bars 13 and 14
Since the positional relationship before thermal deformation is easily maintained, the amount of deformation is reduced as compared with the conventional one.

[0029]

As described above, according to the present invention, the optical base having the reflecting mirror constituting the optical resonator is hardly affected by deformation of the oscillator housing due to heat or the like, and the emission direction of the laser beam. Of the present invention, it is possible to improve the stability over time, and to maintain laser irradiation with high accuracy.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an optical base support structure of a quadrature excitation laser oscillator according to a first embodiment of the present invention.

FIG. 2 is a plan view showing an optical base support structure of the quadrature excitation laser oscillator according to the first embodiment of the present invention.

FIG. 3 is a side view showing the optical base support structure of the quadrature excitation laser oscillator according to the first embodiment of the present invention.

FIG. 4 is a plan view showing a thermal deformation state of the optical base support structure of the orthogonally pumped laser oscillator according to the first embodiment of the present invention.

FIG. 5 is a sectional view showing a support rod connection structure used in the optical base support structure of the quadrature excitation laser oscillator according to the first embodiment of the present invention.

FIG. 6 is a sectional view showing a support rod connection structure used in the optical base support structure of the quadrature excitation laser oscillator according to the first embodiment of the present invention.

FIG. 7 is a side view showing a support rod connection structure used in the optical base support structure of the quadrature excitation laser oscillator according to the first embodiment of the present invention.

FIG. 8 is a side view showing an optical base support structure of a quadrature excitation laser oscillator according to a second embodiment of the present invention.

FIG. 9 is a side view showing a support rod connection structure used in an optical base support structure according to a second embodiment of the present invention.

FIG. 10 is a side view showing a thermally deformed state of the optical base support structure according to the second embodiment of the present invention.

FIG. 11 is a side view showing an optical base support structure of a conventional orthogonally pumped laser oscillator.

FIG. 12 is a plan view showing an optical base support structure of a conventional orthogonally pumped laser oscillator.

FIG. 13 is a perspective view showing the internal structure of a general quadrature excitation laser oscillator.

FIG. 14 is a plan view showing a thermally deformed state of the conventional optical base support structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Oscillator housing 6 Total reflection mirror 7 Rear optical base 8 Partial reflection mirror 9 Front optical base 13, 14 Support rod 20, 21 Bracket 21a Holding bracket part 21b Slide table

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Kyoko Yamada 2-3-2 Marunouchi, Chiyoda-ku, Tokyo F-term in Mitsubishi Electric Corporation (reference) 5F071 AA05 DD01 DD08 EE04 JJ06

Claims (1)

[Claims] An oscillator housing, a first optical base provided outside the oscillator housing and having a first reflecting mirror, and a first optical base opposed to the first optical base via the oscillator housing, A second optical base having one reflecting mirror and a second reflecting mirror forming a resonator; and the first optical base and the second optical base provided on an outer surface of the oscillator housing. A first connecting member and a second connecting member, the first supporting member being provided at the center of the outer surface in the erection direction and holding and fixing the first connecting member; and the outer surface A mounting portion fixed to a central portion of the mounting direction and a movable holding portion that engages with the mounting portion and holds the second connection member, and the displacement of the outer surface in a direction perpendicular to the mounting direction. And a second support member with which the mounting portion and the moving holding portion move relative to each other. A quadrature-pumped laser oscillator characterized in that: