JPH0555669A - Solid laser equipment - Google Patents

Abstract

PURPOSE:To obtain a solid laser equipment capable of stable and suitable laser working without excess or lack of laser energy, by changing the waveform of pulse laser energy of pulse laser oscillation by controlling supply energy to a exciting lamp, in a solid state laser. CONSTITUTION:A power supply equipment for a exciting lamp 17 is constituted of the following; a main unit 8 wherein a second main switching element 11, a forced discharge circuit 9, and a voltage detection circuit 12 are added to the conventional power supply equipment for solid pulse laser, and a subunit 6 constituted of a second charging power supply 19, a third switching element 22, a second diode 23, a third inductor 24, and a subcapacitor bank 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state laser device used in industrial equipment and medical equipment and excited by a flash lamp or the like.

[0002]

2. Description of the Related Art Solid-state laser devices are used as industrial equipment in the semiconductor field, such as trimming and scribing, marking, soldering, welding and cutting, and their fields of use are expanding year by year. The expansion of its use is remarkable.

First, a solid-state laser device will be described with reference to the drawings. FIG. 3 shows the configuration of the solid-state laser device. In FIG. 3, 17 is an excitation lamp such as a flash lamp for exciting the laser medium 28, 29 is a reflector (hereinafter, referred to as a reflector) for reflecting light energy (hereinafter, referred to as excitation light), and 30 is an excitation. Is a power supply device for driving the lamp, 31 is a partial reflection mirror, and 32 is a total reflection mirror. The reflector 29 is for reflecting the excitation light and making it efficiently incident on the laser medium. In this example, the reflector 29 has a cylindrical shape, but is not limited to the cylindrical shape.

In the solid-state laser device having such a configuration, the pumping light emitted from the pumping lamp 17 is directly or reflected by the reflector 29 and is incident on and absorbed by the laser medium 28 to excite the laser medium 28 and An optical resonator composed of 28 and a partial reflection mirror 31 and a total reflection mirror 32 arranged on both sides of the same makes a resonance state, and the light is extracted from the partial reflection mirror 31 to the outside.

Next, FIG. 5 shows a circuit configuration of a conventional power supply device for a solid-state laser. In FIG. 5, 1 is a first inductance for limiting the charging current of the capacitor bank 2, 3 is a switching element for controlling the discharge of the capacitor bank 2, and 4 is a limiting current flowing into the excitation lamp 17. The second inductance, 5 is a diode for preventing backflow, 7 is a gate signal control circuit for controlling the switching element 3, and 10 is a power source for charging the capacitor bank 2.

The operation of the solid-state laser power supply device configured as described above will be described. In the power supply device for the solid-state laser shown in FIG. 5, the charging power supply 10 charges the capacitor bank 2 via the inductance 1. The charging energy of the capacitor bank 2 charged to a constant voltage is supplied to the excitation lamp 17 by the switching element 3. At this time, the energy from the capacitor bank 2 supplied to the excitation lamp 17 is controlled by the gate signal control circuit 7 and supplied for a certain period of time. Excitation lamp 1
The energy to 7 causes the excitation lamp 17 to emit light for a certain period of time, and as described with reference to FIG.
Is excited, is brought into a transmitting state by the optical resonator, and is emitted as laser light from the partial reflecting mirror 31.

[0007]

In the conventional solid-state laser power supply having the above configuration, the energy supplied to the excitation lamp 17 is the charging energy of the capacitor bank 2 and is therefore constant over time. , Excitation lamp 1
The excitation light emitted from 7 cannot be changed with time. Therefore, when performing laser processing using a solid-state pulse laser, the energy of laser light cannot be continuously and arbitrarily changed, and the energy (irradiation form) can be arbitrarily changed with the passage of time of laser light. Therefore, it is difficult to perform stable laser processing under optimal conditions due to excessive laser energy or lack of laser energy. Especially in laser welding, laser cutting, etc., unnecessary carbonized layers and heat There was a problem such as causing deterioration such as distortion.

The present invention solves the above-mentioned conventional problems, and when performing laser processing using a pulse laser,
By arbitrarily changing the energy (optical waveform) of the pulsed laser light over time, stable and optimal laser processing without excessive laser energy or lack of laser energy is possible, as well as the deterioration of the surface of the laser processed material. An object of the present invention is to provide a solid-state laser device that can be reduced.

[0009]

In order to achieve the above object, a solid-state laser device of the present invention has a main capacitor bank, a first charging power source for charging the main capacitor bank, and a main capacitor bank. The first inductance for limiting the charging current, the second inductance for limiting the discharge of the charge charged in the main capacitor bank, the first diode for preventing the backflow, and the charge for the charge stored in the main capacitor bank A first switching element for controlling discharge, a second switching element connected in series between the positive output terminal of the first charging power supply and the first inductance, and a main capacitor bank connected in parallel to the main capacitor bank A voltage detection circuit for detecting the charging voltage of the sub-capacitor bank described later together with the charging voltage of When the excitation lamp is connected to the positive and negative output terminals, it is equipped with a forced discharge circuit connected to form a closed circuit with the main capacitor bank via a switching element and positive and negative output terminals for connecting the excitation lamp. The main capacitor bank, the first switching element, the first diode, and the second inductance are connected to form a closed circuit via the exciting lamp, and the sub capacitor bank and the sub capacitor bank are charged. A second charging power supply for controlling the discharge of the charge stored in the sub-capacitor bank, a third switching element for controlling the discharge of the charge stored in the sub-capacitor bank, and a second diode for preventing backflow and for limiting the discharge of the charge stored in the sub-capacitor bank. Lamp having a third inductance and a positive / negative output terminal for connecting the lamp for excitation A sub-capacitor bank, a third switching element, a second diode, and a third inductance connected to form a closed circuit via an excitation lamp when connected to positive and negative output terminals; A gate signal control circuit for controlling the opening and closing of each switching element and an excitation lamp are used, and the laser medium is excited by the excitation lamp.

[0010]

According to the above construction, when energy is supplied to the excitation lamp, a plurality of switching elements and a forced discharge circuit are variously combined to control charging and discharging of a plurality of capacitor banks. It becomes possible to change the total energy supplied to the lamp, and by varying the amount of light (light energy) emitted from the excitation lamp, the individual pulse energy of pulse oscillation can be varied continuously and variously. It is possible to provide a solid-state laser device capable of performing laser processing under optimum conditions.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the solid-state laser device of the present invention will be described below with reference to the drawings.

FIG. 1 shows an overall circuit diagram of the solid-state laser device of the present invention. In FIG. 1, the same parts as those in FIG. 5 showing the circuit of the conventional example are denoted by the same reference numerals, and therefore the points different from FIG. 5 will be described. First, 8 is a main unit, and in the main unit 8, a voltage detection circuit 12 is arranged in parallel with a capacitor bank 2 (hereinafter referred to as a main capacitor bank).
Are connected to detect the charging voltage of the main capacitor bank 2 and the charging voltage of the sub-capacitor bank 25, which will be described later, and respond to various controls. Between the cathode of the first switching element 3 and the ground line connected to the negative terminal 14 of the charging power source 10 (hereinafter referred to as the first charging power source), the forced discharge circuit 9 and the first charging power source 10 are connected. Positive terminal 13 and first
The second switching element 11 between the inductances 1 of
Are connected. Reference numeral 15 is a positive output terminal of the main unit 8 and 16 is a negative output terminal. Reference numeral 6 denotes a subunit, which includes a second charging power source 19, a third switching element 22, a second diode 23 for preventing backflow, and a third inductance 24 for limiting the charging current from the subunit 6. Has been done. 20 is a charging power source 1
9 is a positive output terminal, 21 is a negative output terminal, 25 is a sub capacitor bank, 26 is a positive output terminal of the subunit 6, and 27 is a negative output terminal.

Further, the excitation lamp 17 is connected to the positive and negative output terminals 15 and 16 of the main unit 8 and the positive and negative output terminals 25 and 26 of the subunit 6 so that the three are in parallel, and the gate signal is supplied. The control circuit 18 is connected to input signals to the gates of the switching elements 3, 11 and 22.

A power supply device of the solid-state laser device configured as described above will be described with reference to FIGS. 1 and 4. In FIG. 4, SW indicates a switching element, and the number following SW indicates the component code (number) of the switching element in the circuit diagram of FIG. 1.

First, in the main unit 8, the electric energy charged in the main capacitor bank 2 is supplied to the exciting lamp 17 via the switching element 3 at a constant value which does not change with time. As shown in FIG. 4A, in order to increase the input energy to the excitation lamp 17 during the energy supply time T, the charging energy of the sub-capacitor bank 25 of the subunit 6 is set to the time T.
This can be realized by making the third switching element 22 conductive and supplying it to the excitation lamp 17 in the middle of. In this case, the relationship between the voltages at points A and B in the circuit diagram shown in FIG.
_B > V _A is set by the voltage detection circuit 12, the first charging power source 10 and the second charging power source 19, and the third switching element 22 is set by the gate signal control circuit 18.
To control.

On the contrary, as shown in FIG. 4B, in order to sharply reduce the input energy to the excitation lamp 17 in the middle of the energy supply time T, it is necessary to set V _A > V _B beforehand. The voltages of the first charging power source 10 and the second charging power source 19 are set, and at the beginning of time T, the excitation lamp 1
7 is supplied with energy from both the main unit 8 and the subunit 6, and the forced discharge circuit 9 shown in the circuit diagram of FIG. 1 is closed in the middle of the time T to transfer the charging energy of the main capacitor bank 2 to the ground line. It can be achieved by releasing.

Further, as shown in FIG. 4 (c), in order to gradually reduce the input energy to the excitation lamp during the energy supply time T, as in the case of FIG. 4 (b), V is previously set. First charging power source 1 so that _A > V _B
0 and the voltage of the second charging power source 19 are set, energy is supplied to the excitation lamp 17 from both the main unit 8 and the subunit 6 at the beginning of the time T, and the energy is supplied in the middle of the time T. By opening the switching element 11 of No. 2, the main capacitor bank 2 is connected to the first charging power source 10
It is possible to gradually reduce the charging voltage of the main capacitor bank 2 and reduce the energy supplied to the excitation lamp 17 by disconnecting the main capacitor bank 2 and discharging the main capacitor bank 2 without replenishing the charging energy of the main capacitor bank 2.

As described above, the gate signal control circuit 18 controls the forced discharge circuit 9 of the main unit 8 and the plurality of switching elements provided in the main unit 8 and the subunit 6.
Thus, the pulse waveform can be changed in the middle of the energy supply time T by controlling the opening and closing in cooperation with various combinations.

By providing a plurality of sets of sub-units 6 for one set of the main unit 8, these pulse waveform controls can be controlled in various ways, and the effect can be further expanded. In Fig. 2, for one set of main unit 8 and one excitation lamp,
An example in which three sets of subunits 6 are connected is shown.

[0020]

As is apparent from the above description, by providing a plurality of sets of sub-units for one set of main unit and one excitation lamp, a plurality of capacitor banks and a plurality of switching elements can be provided. In addition, by providing various combinations of control by the signal of the gate signal control circuit including the voltage detection circuit and the forced discharge circuit of the main unit, the energy supply to the excitation lamp can be performed over time. At the same time, it is possible to continuously and variously change, and it is possible to suppress the occurrence of unnecessary alteration on the surface of the workpiece, and it is possible to perform laser processing under optimum processing conditions.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a power supply device used in a laser processing apparatus of the present invention.

FIG. 2 is a block diagram showing an example in which a plurality of subunits are used in the same power supply device.

FIG. 3 is a device configuration diagram of the present invention and a conventional solid-state laser device.

4A is a pulse input waveform diagram in which energy increases during energization by the power supply device of the present invention, and FIG. 4B is a pulse input waveform diagram in which energy rapidly decreases during energization by the power supply device of the present invention. (C) is a pulse input waveform diagram in which energy gradually decreases during energization by the power supply device of the present invention.

FIG. 5 is a circuit diagram of a conventional power supply device used in a solid-state laser device.

[Explanation of symbols]

 1 First Inductance 2 Main Capacitor Bank 3 First Switching Element 4 Second Inductance 5 First Diode 6 Sub Unit 8 Main Unit 9 Forced Discharge Circuit 10 First Charging Power Supply 11 Second Switching Element 12 Voltage Detection Circuit 13 Positive output terminal of first charging power source 15 Positive output terminal of main unit (positive output terminal) 16 Negative output terminal of main unit (negative output terminal) 17 Excitation lamp 18 Gate signal control circuit 19 Second charging power source 22 Third switching element 23 Second diode 24 Third inductance 25 Sub-capacitor bank 26 Sub unit positive output terminal (positive output terminal) 27 Sub unit negative output terminal (negative Output terminal) 28 Laser medium

Claims (1)

[Claims] 1. A main capacitor bank, a first charging power source for charging the main capacitor bank, and a first inductance for limiting a charging current charged in the main capacitor bank and the main capacitor bank are charged. A second inductance for limiting the discharge of electric charge, a first diode for preventing backflow, a first switching element for controlling the discharge of the electric charge charged in the main capacitor bank, and a positive output of the first charging power source. A second switching element connected in series between the terminal and the first inductance, and a voltage detection circuit connected in parallel to the main capacitor bank for detecting the charging voltage of the main capacitor bank and the charging voltage of the sub-capacitor bank described later. Make a closed circuit with the main capacitor bank via the first switching element A positive discharge terminal and a negative output terminal for connecting the forced discharge circuit and the excitation lamp connected to the main capacitor bank and the first switching element when the excitation lamp is connected to the positive and negative output terminals. A main unit in which the first diode and the second inductance are connected via an exciting lamp to form a closed circuit; a sub-capacitor bank; a second charging power supply for charging the sub-capacitor bank; A third switching element for controlling the discharge of the charges charged in the capacitor bank, a second diode for preventing backflow, and a third diode for limiting the discharge of the charges charged in the sub-capacitor bank.
Of the sub-capacitor bank, the third switching element, and the second diode when the excitation lamp is connected to the positive and negative output terminals The excitation lamp includes a sub-unit in which the third inductance is connected so as to form a closed circuit via the excitation lamp, a gate signal control circuit that controls opening / closing of each of the switching elements, and the excitation lamp. Solid-state laser device that excites the laser medium by means of a laser.