JPH088383B2 - High frequency discharge excitation laser device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a high-frequency discharge excitation laser device in which a laser medium gas is circulated in a discharge part to form a laser oscillator, and more particularly to a high-frequency discharge excitation laser device including a high-frequency inverter. .

[Conventional technology]

In order to improve the efficiency of laser output, a high frequency discharge excitation laser device has been used. FIG. 3 is a connection diagram of a conventional high frequency discharge excitation laser device.

In the figure, reference numeral 1 denotes a DC power source, which has a built-in stabilizing circuit for rectifying a three-phase commercial AC input into a DC voltage and keeping the DC voltage at a constant value as necessary. Reference numeral 2 is a high-frequency inverter, which converts a DC input into a high-frequency AC. The frequency in this case is 1 to several MHz. Reference numeral 3 denotes a matching circuit, which uses a π-type circuit in this example, and is a circuit for performing impedance matching between the output of the high frequency inverter 2 and the coaxial cable 4. Reference numeral 4 denotes a coaxial cable, which transmits the high frequency power from the high frequency inverter 2. 5 is a discharge part such as a laser tube, which has electrodes 6a and
6b is provided, and the laser medium gas is circulated inside.
By applying high frequency power to the electrodes 6a and 6b, discharge is excited and laser light in the axial direction is oscillated and amplified. In this case, the matching circuit 3 and the discharging unit 5 are placed at a distance considerably away from the high frequency inverter 2 and the like.

[Problems to be solved by the invention]

However, when such a coaxial cable 4 is used,
The impedance of the coaxial cable 4 is usually 50Ω, the matching characteristics with the high frequency inverter 2 and the discharging unit 5 are poor, and a circuit such as automatic tracking is required, and the matching circuit 3 becomes complicated and expensive.

 Further, the high frequency loss in the coaxial cable 4 is large.

Further, since the coaxial cable 4 originally has a small number of things that transmit a large amount of power, it is expensive, and when the laser head is separated from the cabinet in which the high frequency inverter is built, the distance is limited.

In addition, there is a problem in that shields must be provided on both sides of the coaxial cable to prevent radio interference.

An object of the present invention is to solve the above-mentioned problems and to provide a high-reliability high-frequency discharge pump laser device by directly connecting a high-frequency inverter or the like to an optical resonator section, thereby eliminating the need for a coaxial cable or the like.

[Means for solving problems]

In the present invention, in order to solve the above problems, in a high-frequency discharge excitation laser device that performs laser oscillation by circulating a laser medium gas in a discharge part such as a laser tube, rectifies an AC input and outputs a DC power DC A power supply, a high-frequency inverter that is arranged at a distance from the DC power supply and is connected by a cable, and that supplies high-frequency power to the discharge unit, and a matching circuit that performs impedance matching between the high-frequency inverter and the discharge unit. Then, a high-frequency discharge pumped laser device is provided, in which the high-frequency inverter and the matching circuit are directly connected to each other and arranged adjacent to an optical resonator section including the discharge section.

[Action]

Directly connect the high frequency inverter and matching circuit,
Since it is arranged adjacent to the optical resonator part including the discharge part,
The distance between the high-frequency inverter, the matching circuit, and the optical resonator becomes extremely short, which eliminates the need for a coaxial cable and impedance matching with the coaxial cable.

〔Example〕

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

FIG. 1 is a circuit diagram of a high frequency discharge excitation laser device of the present invention. In FIG. 1, the same elements as those in FIG. 3 are designated by the same reference numerals. In the figure, reference numeral 1 denotes a DC power supply, which has a built-in stabilizing circuit for rectifying a three-phase AC input into a DC power and keeping the DC voltage at a constant value as necessary. Reference numeral 2 is a high frequency inverter, which converts a DC input into a high frequency AC by the inverter. The frequency in this case is 1 to several MHz
Is. Reference numeral 3 denotes a matching circuit, which uses a π-type circuit in this example, and is a circuit for performing impedance matching between the output of the high frequency inverter 2 and a discharge unit described later. Reference numeral 5 denotes a discharge part such as a laser tube, which has electrodes 6a at both ends.
And 6b, and the laser medium gas is circulated inside. By applying high-frequency power to the electrodes 6a and 6b, discharge is excited to oscillate and amplify laser light in the axial direction. In this case, the high-frequency inverter 2 and the matching circuit 3 are placed at the same place as the normal power unit 5, so that the distance between the matching circuit 3 and the discharge unit 5 is small, a coaxial cable is not required, and impedance matching is performed. In consideration of the impedance between the high frequency inverter 2 and the discharging unit 5, the configuration of the matching circuit 3 can be easily designed. Further, the shielding for eliminating the radio wave interference may be performed collectively including the matching circuit 3 and the discharging unit 5, which is simple.

FIG. 2 is a schematic layout of the high frequency discharge pumped laser device of the present invention. The high frequency inverter 2 and the matching circuit 3 are arranged adjacent to the optical resonator unit 7 including the discharge unit 5. As shown in the figure, the distance between the matching circuit 3 and the optical resonator section 7 is extremely small, it is not necessary to use a coaxial cable, and the shape is sufficiently large as compared with the optical resonator section 7 as shown in FIG. Can be created in Reference numeral 8 is an output of laser light.

By disposing such a device in which the high frequency inverter 2, the matching circuit 3, and the optical resonator unit 7 are integrated at the head of the laser processing machine and the tip of the arm of the robot,
It is possible to configure a laser processing machine having a simple configuration.

〔The invention's effect〕

As described above, in the present invention, by disposing the high frequency inverter and the matching circuit adjacent to the optical resonator section, a coaxial cable is not required, loss in the coaxial cable is eliminated, and impedance matching is facilitated.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a high frequency discharge excitation laser device of the present invention, FIG. 2 is a schematic layout diagram of the high frequency discharge excitation laser device of the present invention, and FIG. 3 is a connection diagram of a conventional high frequency discharge excitation laser device. . 1 …… DC power supply 2 …… High frequency inverter 3 …… Matching circuit 4 …… Coaxial cable 5 …… Discharge section 7 …… Optical resonator section 8 …… Laser light

Claims (1)

[Claims] 1. A high-frequency discharge excitation laser device for oscillating a laser by circulating a laser medium gas in a discharge part such as a laser tube, a DC power source for rectifying an AC input and outputting a DC power, and a distance from the DC power source. And a matching circuit that is connected by a cable and supplies high-frequency power to the discharge unit, and a matching circuit that performs impedance matching between the high-frequency inverter and the discharge unit. A high-frequency discharge excitation laser device, wherein a circuit is directly connected and is arranged adjacent to an optical resonator section including the discharge section.