JP3047596B2 - Axial laser oscillator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axial-flow laser oscillator having a stabilized laser output used in a cutting machine or the like and having a reduced size.

[0002]

2. Description of the Related Art A conventional axial flow laser oscillator will be described below. In FIG. 4, 2a and 2b are resonator holding plates, 3 is an output mirror, 4 is a total reflection mirror, 5a and 5b are gas connection blocks, and 6a, 6b and 7a and 7b are discharge tube 6 and discharge tube 7 mounting. Flange, 9 is an air supply duct, 11 is a blower,
13 is a resonance base, 15 is a collective block, 16 is a collective block support insulator, 17a and 17b are exhaust ducts, 18 is a glass cooler, and 19 is a resonator base. Reference numeral 12 denotes a laser optical axis of the resonator.

[0003] The relationship between the components and the operation of the axial flow laser oscillator comprising the above components will be described. FIG.
As shown in the figure, the resonator holding plates 2a and 2b are attached to both ends of the resonator base 13, and the output mirror 3, the total reflection mirror 4, the connection block 5, the discharge tubes 6, 7, and the assembly block 15 are arranged coaxially. The assembly block 15 is fixed on the resonator base 13 with the support insulator 16, and the discharge tube 6 and the discharge tube 7 are attached to the connection flange 5 and the assembly block 15 by the attachment flanges 6a, 6b and the attachment flanges 7a, 7b. The gas laser medium is equally divided and supplied from the air supply duct 9 by the blower 11 to the two discharge tubes 6 and 7 through the connection blocks 5a and 5b attached to the resonator holding plates 2a and 2b. However, it is excited by discharge by a discharge electrode to which a high voltage generated by a high voltage power supply is applied, and outputs a laser beam.
The gas laser medium that has been discharged and heated by passing through the discharge tube 3 and the discharge tube 7 is collected into one by the collective block 15 at the center of the resonator, and is exhausted from the exhaust duct 17a. The exhausted gas laser medium is cooled by the gas cooler 18 connected to the exhaust duct 17a, and then returned to the blower 11 again through the exhaust duct 17b.

In general, this type of axial-flow laser oscillator is
The gas laser medium that has once exited the discharge tube at the collecting block is combined into a single unit, and the gas cooler and the collecting block are connected by an exhaust duct. The piping collectively discharges the heated gas laser medium. Through and connected to a gas cooler mounted separately from the laser resonator.

In a conventional axial flow laser oscillator, a gas cooler 18 is placed beside a resonator, and the resonator and the blower 11 are connected to the gas cooler 18 by exhaust ducts 17a and 17b. Therefore, the size of the oscillator including the exhaust ducts 17a and 17b is larger than that of the resonator itself.
Further, the heated gas laser medium is further provided with an assembly block 15 placed on the laser optical axis 12 and a gas cooler 1.
When the oscillator is started to heat the exhaust duct 17a connecting the collecting block 8 and the collecting block 15, or when the discharge input is changed to adjust the laser output, expansion and contraction due to the temperature change of these pipes occurs, Since the temperature has risen, the resonator base 13 is also warmed by radiant heat to make the temperature distribution of the resonator base 13 non-uniform.

[0006]

As described above, in the conventional configuration, the expansion and contraction of each pipe and the non-uniform temperature distribution of the resonator base occur, so that the laser optical axis of the laser resonator is out of order and the output fluctuates. In addition, there is a problem that the shape becomes larger.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and to provide a downsized axial-flow laser oscillator with stabilized laser output.

[0008]

In order to achieve this object, an axial flow type laser oscillator according to the present invention is arranged such that a gas cooler is located on a laser optical axis of a resonator and fixed to a resonator base, and both sides thereof are provided. A structure in which a discharge tube is attached with a hole through which laser light passes on the surface, and a cavity base is formed by a hollow tube whose both end surfaces are closed, and the internal space is provided with the outlet of the gas laser medium of the gas cooler. It is configured to communicate with the exhaust duct.

[0009]

With this configuration, the length of the exhaust duct connecting the resonator, the gas cooler, and the blower is shortened, and the gas laser medium heated by discharge excitation and cooled immediately after exiting the discharge tube is cooled. This eliminates a rise in temperature of the resonator base due to a rise in temperature or radiant heat.

[0010]

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

In FIGS. 1 to 3 showing one embodiment of the present invention, the same parts as those of the conventional example are denoted by the same reference numerals, and the description will be omitted.

As shown in FIGS. 1 to 3, the discharge tube 6 or 7 has one end attached to the connection block 5a or 5b by an attachment flange 6a or 7a, and the other end attached to the gas cooler 8 by an attachment flange 6b or 7b. Is attached to the through hole 8a or 8b through which the laser light and the gas laser medium opened on both sides pass, and is arranged so as to be coaxial with the laser optical axis 12 of the resonator together with the output mirror 3 and the total reflection mirror 4. I have.

The gas cooler 8 is provided with a gas and water heat exchange core 14 below the through holes 8a and 8b, and a casing is provided on the lower surface where the casing extends in the optical axis direction of the resonator before and after the heat exchange core 14. The cooling gas outlets 8c and 8d are formed to cool the high-temperature gas laser medium entering from the upper surface of the heat exchange core 14,
The cooling gas is discharged from outlets 8c and 8d.

The resonator base 1 has a rectangular internal space 1a whose section perpendicular to the optical axis of the resonator has a rectangular cross section, and is formed by a hollow tube whose both end faces in the optical axis direction are closed. The upper and lower ridge lines along the are provided with walls having the same thickness as the cross-sectional plate thickness to increase the bending rigidity due to the vertical load. The gas cooler 8 is closely fixed on the plane of the upper surface of the resonator base 1, and has the same pitch and the same hole diameter as the cooling gas outlets 8 c and 8 d of the gas cooler 8. The gas cooler 8 is fixed to the resonator base 1 by opening the inlets 1b and 1c and making the outlets 8c and 8d coincide with the inlets 1b and 1c, respectively.
A cooling gas outlet 1d is provided on the lower surface of the resonator base 1,
Exhaust duct 10 connecting blower 11 and resonator base 1
Is installed.

The operation of the axial-flow type laser oscillator configured as described above will be described below. Into the discharge tubes 6 and 7, the gas laser medium is connected to the connection blocks 5 a and 5 b by the air supply duct 9 by the blower 11 in the same manner as described in the conventional example.
And a laser beam is oscillated by generating glow discharge between discharge electrodes to which a high voltage generated by a high voltage source is applied. The oscillated laser light is
The light is amplified and reciprocated between the output mirror 3 and the total reflection mirror 4 and finally taken out of the output mirror 3. The gas laser medium whose temperature has risen in the discharge tubes 6 and 7 is recovered by the heat exchange core 14 of the gas cooler 8 as shown by the arrow in FIG. 3, is cooled, and is cooled by the outlets 8 c and 8 d and the resonator base 1. The gas enters the internal space 1a of the resonator base 1 through the inlets 1b and 1c, passes through the exhaust duct 10 from the outlet 1d, returns to the blower 11, and is sent again to the discharge tubes 6 and 7 through the air supply duct 9.

Accordingly, there is no pipe other than the exhaust duct 10 for passing the gas laser medium out of the laser resonator through the gas cooler 8 and returning to the blower 11, and the gas cooler 8 is incorporated inside the laser resonator. Therefore, unlike the conventional example, the pipes from the discharge tubes 6 and 7 to the blower 11 are not heated and expanded by the high-temperature gas laser medium exiting the discharge tubes 6 and 7, and the radiant heat from the gas laser medium is not increased. Does not occur. Further, since the cooled gas laser medium exiting the gas cooler 8 passes through the inside of the resonator base 1, the temperature distribution of the resonator base 1 does not become uneven. Therefore, the laser optical axis of the laser resonator does not become out of order during the operation of the oscillator.

As described above, according to the present embodiment, the gas cooler 8 is disposed on the laser optical axis of the resonator and the resonator base 1 is provided.
And the discharge tubes 6 and 7 are attached by making holes through which laser light passes from both sides.
The laser tube has a configuration in which an outlet of the gas laser medium of the gas cooler 8 is communicated with the internal space 1a of the resonator base 1 and the internal space 1a is communicated with the exhaust duct 10 using a hollow tube whose both ends are closed. The output of the laser can be kept stable by suppressing the deviation of the laser optical axis during oscillation. Further, the gas cooler 8 is incorporated in the laser optical axis of the laser resonator,
Since the exhaust duct 10 connecting the laser resonator and the blower 11 can be shortened, the overall shape of the oscillator can be reduced.

[0018]

As is clear from the above description of the embodiment, according to the present invention, the gas cooler is located on the laser optical axis of the resonator and fixed to the resonator base, and the laser light is applied to both side surfaces thereof. A structure in which a discharge tube is attached with a hole through it, and a cavity base is formed by a hollow tube whose both end faces are closed, the internal space of which is communicated with the outlet of the gas laser medium of the gas cooler, and an exhaust duct With this configuration, the laser output is stabilized, and a compact and excellent axial flow laser oscillator can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing the concept of an axial-flow laser oscillator according to an embodiment of the present invention.

FIG. 2 is a schematic side sectional view of a gas cooler of a coaxial flow type laser oscillator and its periphery.

FIG. 3 is a schematic front sectional view of a gas cooler of a coaxial flow type laser oscillator and its periphery.

FIG. 4 is a schematic front view showing the concept of a conventional axial-flow laser oscillator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Resonator base 1a Internal space 6, 7 Discharge tube 8 Gas cooler 10 Exhaust duct 12 Laser beam axis

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-235440 (JP, A) JP-A-4-133483 (JP, A) JP-A-62-216384 (JP, A) JP-A-61-216 14783 (JP, A) JP-A-61-27693 (JP, A) JP-A-5-110177 (JP, A) JP-A-58-166785 (JP, A) Japanese Utility Model Laid-Open No. 61-1863 (JP, U) Japanese Utility Model Showa 58-175887 (JP, U) Japanese Utility Model Showa 58-37166 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01S 3/041 H01S 3/03-3/038 H01S 3/097-3/0977

Claims (1)

(57) [Claims] 1. A laser oscillator having a plurality of discharge tubes having discharge electrodes, a resonator holding plate having output mirrors and total reflection mirrors mounted on both ends thereof on a resonator base, and a blower of a gas laser medium. An air supply duct and an exhaust duct connecting the laser oscillator and the blower, a gas cooler, a high voltage power supply, and the discharge electrode connected to the high voltage power supply with the gas laser medium in the discharge tube. An axial flow type laser oscillator that generates laser light by being excited by electric discharge, wherein the gas cooler is located on the laser optical axis of the laser resonator, fixed to the resonator base, and provided on both side surfaces thereof. A configuration in which the discharge tube is mounted by making a hole through which laser light passes coaxially with the laser optical axis of the laser resonator, and the resonator base is formed by a hollow tube whose both end faces are closed, and an internal space thereof is formed. The gas An axial-flow laser oscillator configured to communicate with an outlet of a gas laser medium of a cooler and with the exhaust duct.