JP2002359422A - Q-switch laser controller and laser - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress fluctuations of the pulse width of laser beam and wave- height value of laser beam energy, when Q-switch repetition frequency is changed. SOLUTION: A timing control circuit 4 outputs a pulse signal 12 to a semiconductor element 6, in synchronism with a pulse signal 11 outputted from a repetition signal generator 1. A pulse width setting circuit 3 maintains in advance the data of pulse width of the pulse signal 12, and the timing control circuit 4 outputs the pulse signal 12 based on the data. The semiconductor element 6 causes a power source 7 to turn on, when the pulse signal 12 is at high level to cause an excitation light source 23 to turn on. The timing control circuit 4 outputs a Q-switch signal 13 to a Q-switch driver 5, in synchronism with the pulse signal 12. The Q-switch driver 5 turns a Q-switch element 24 on, when the Q-switch signal 13 is at high level, to cause the energy level of a laser rod 22 to make transition to a low level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a Q-switch laser control device for controlling a Q-switch laser oscillator and a laser device.

[0002]

2. Description of the Related Art FIG. 6 is an explanatory diagram showing an example of the configuration of a conventional Q-switch laser control device. FIG. 6 shows the Q-switch laser oscillator 21 together with the Q-switch laser control device 101. In the following description, the Q-switched laser oscillator is referred to as a Q-switched laser oscillator head. The Q-switch laser control device 101 controls the Q-switch laser oscillator head 21 to generate laser light. The conventional Q-switch laser control device 101 includes a repetitive signal generator 10
2, a Q switch driver 105, and a power supply 107. The repetitive signal generator 102 outputs a pulse signal 111 to the Q switch driver 105. The Q switch driver 105 drives the Q switch element 24 in synchronization with the pulse signal 111 so that the Q switch element 24 included in the Q switch laser oscillator head 21 is turned on. Further, the power supply 107 continuously turns on the excitation light source 23 included in the Q-switched laser oscillator head 21.

A Q-switched laser oscillator head 21 includes a laser rod 22, an excitation light source 23,
4, a total reflection mirror 25, and an emission mirror 26. As the excitation light source 23, a laser diode or a xenon lamp is used. The laser rod 22 includes an excitation light source 23
, And becomes a high energy level. Then, when the Q switch element 24 is turned on, the energy level changes from a high level to a low level, and at this time, the laser rod 22 emits light of a specific wavelength. The total reflection mirror 25 and the emission mirror 26 form an optical resonator, and cause the laser rod 22 to emit stimulated light. Laser rod 22
A part of the light emitted by the laser beam passes through the emission mirror 26 and is emitted outside as laser light.

When the conventional Q-switch laser control device 101 controls the Q-switch laser oscillator head 21, the Q-switch element 24 repeats the ON state and the OFF state at the same frequency as the repetition frequency of the pulse signal 111. Hereinafter, the repetition frequency of the ON state and the OFF state of the Q switch element 24 is referred to as a Q switch repetition frequency. Q
When the switch element 24 is in the off state, the laser rod 22 receives energy from the excitation light source 23 and is excited to a high energy level. This energy level is proportional to the product of the light intensity of the excitation light source 23 and the irradiation time. Since the excitation light source 23 is continuously turned on, it keeps exciting the energy level when the Q switch is in the off state. When the Q switch element 24 is turned on,
The laser rod 22 emits the energy stored in the off state in a short time. Therefore, laser light having a high peak value of energy and a short pulse width can be obtained.

[0005] The Q-switch laser control device and the Q-switch laser oscillator head are applied to a laser processing device such as a trimmer device. The trimmer device is a device for processing a resistance value of a chip resistor to a desired value. The chip resistor processed into the trimmer device has a configuration in which a paste for forming a resistive film is applied to the surface of a base material such as a ceramic. The trimmer device irradiates this paste with laser light,
The paste is evaporated and removed by the photothermal reaction, and the resistance value of the chip resistor is adjusted to a desired value. When the chip resistor is irradiated with laser light, the laser light is reflected by a mirror mounted on the galvanometer, and the reflected light is irradiated. Then, laser light is scanned over the surface of the chip resistor by changing the angle of the mirror of the galvanometer.

The processing conditions of the chip resistor are changed according to a desired resistance value. When the desired resistance is small, Q
The switch repetition frequency is reduced, and the scanning speed of the laser beam on the surface of the chip resistor is reduced. When the desired resistance value is large, the repetition frequency of the Q switch is increased and the scanning speed is increased. Therefore, the Q-switch laser control device 101 must drive the Q-switch element 24 at the Q-switch repetition frequency according to the desired resistance.

[0007]

In the case of using the conventional Q-switch laser controller 101, if the repetition frequency of the pulse signal 111 is changed to change the Q-switch repetition frequency, the pulse width of the generated laser light, There was a problem that the peak value of the laser light energy also fluctuated.

When the Q-switch repetition frequency is increased,
The time during which the Q switch element 24 is kept in the off state is shortened, and the energy level excited by the pump light source 23 in the off state is reduced. Therefore, the Q switch element 24
Is turned on, the pulse width of the laser light generated increases, and the peak value of the laser light energy decreases.
Conversely, lowering the Q-switch repetition frequency increases the off-state duration of the Q-switch 24, during which the laser rod 22 is over-excited. For this reason, the pulse width of the generated laser light becomes short, and the peak value becomes high.

Such a Q-switch laser control device 10
When 1 is applied to a trimmer device, when the Q-switch repetition frequency is increased, the peak energy is small (the peak value is low), the pulse width is widened, and the heat accumulation on the workpiece increases. As a result, the resistance value becomes unstable due to heat, and it takes time to converge. Therefore, there is a problem that it is not easy to process the chip resistor at high speed. On the other hand, if the Q-switch repetition cycle is reduced, the peak energy of the laser beam becomes excessive, so that not only the paste but also the substrate of the chip resistor may be processed.

Accordingly, the present invention provides a Q-switch capable of suppressing fluctuations in the pulse width of laser light and the peak value of laser light energy when the Q-switch repetition frequency is changed.
It is an object to provide a switch laser control device and a laser device.

The invention described in Japanese Patent Application Laid-Open No. H4-222182 aims to maintain the energy and peak output of laser light even when the repetition frequency of the Q switch is changed, as in the present invention. JP-A-4-22182
The invention described in the above publication achieves the object by causing the excitation lamp to emit light at a voltage that is proportional to the repetition frequency when the repetition frequency of the Q switch is changed.

[0012]

A Q-switch laser control device according to the present invention is a Q-switch laser control device for controlling a Q-switch laser oscillator having a Q-switch element. A signal generating means for generating a second pulse signal with a predetermined pulse width in synchronization with the first pulse signal, and controlling the switching of the Q switch element between an on state and an off state.
Timing control means for generating a switch signal in synchronization with the second pulse signal; and excitation for causing the excitation light source of the Q-switch laser oscillator to repeatedly turn on and off for a predetermined time based on the second pulse signal. A light source lighting control means, and a Q-switch element driving means for switching between an ON state and an OFF state of the Q-switch element based on the Q-switch signal are provided.

For example, the excitation light source lighting control means includes a power supply for lighting the excitation light source, and a semiconductor element for switching the power supply between an on state and an off state, and the semiconductor element is a second element generated by the timing control means. By turning on the power when the pulse signal is at a significant level and turning off the power when the second pulse signal is not at a significant level, the excitation light source can be turned on and off for a predetermined time. Is repeated.

The timing control means generates a Q-switch signal for switching the Q-switch element from an off state to an on state when the laser medium is excited. For example, the timing control means switches the Q switch signal from a non-significant level to a significant level near the timing of switching the second pulse signal from a significant level to a non-significant level.

A pulse width data holding means for holding data of a predetermined pulse width of the second pulse signal, wherein the timing control means has a pulse width corresponding to the data held by the pulse width data holding means; A signal may be generated.

Also, a laser device according to the present invention comprises a Q-switched laser oscillator including an excitation light source for exciting a laser medium, and a Q-switch element for emitting light to the excited laser medium when switched to an on state; A Q-switch laser control device for controlling the Q-switch laser oscillator, wherein the Q-switch laser control device includes a repetitive signal generating means for generating a first pulse signal; Timing control for synchronizing and generating a second pulse signal with a predetermined pulse width, and synchronizing and generating a Q switch signal used for switching control of the ON state and the OFF state of the Q switch element with the second pulse signal Means for applying a predetermined time to the excitation light source of the Q-switched laser oscillator based on the second pulse signal. An excitation light source lighting control means for repeatedly and off the lighting, on the basis of the said Q-switch signal Q
Q switch element driving means for switching between the ON state and the OFF state of the switch element is provided.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing one embodiment of a Q-switch laser control device according to the present invention. FIG. 1 also shows a Q-switch laser oscillator head 21 together with the Q-switch laser control device 1. The Q-switch laser control device 1 controls the Q-switch laser oscillator head 21 and causes the Q-switch laser oscillator 21 to generate laser light.

The Q-switch laser controller 1 includes a repetitive signal generator 2, a pulse width setting circuit 3, a timing control circuit 4, a Q-switch driver 5, a semiconductor device 6,
And a power supply 7. The repetitive signal generator 2 generates a pulse signal (first pulse signal) 11 and outputs it to the timing control circuit 4. The repetition frequency of the pulse signal 11 is variable, and the repetition signal generator 2
The pulse signal 11 is output at a repetition frequency of several hundred hertz to several tens of kilohertz.

As described below, the timing control circuit 4 outputs a pulse signal (second pulse signal) 12. The pulse width setting circuit 3 previously holds the data of the pulse width of the pulse signal 12 and outputs the data to the timing control circuit 4.

The timing control circuit 4 generates a pulse signal 12 in synchronization with the pulse signal 11 input from the repetitive signal generator 2 and outputs the pulse signal 12 to the semiconductor element 6. For example, the pulse signal 12 is output such that the falling timing of the pulse signal 11 and the rising timing of the pulse signal 12 are synchronized. The timing control circuit 4 determines the pulse width of the pulse signal 12 according to the data input from the pulse width setting circuit 3. The semiconductor element 6 functions as a switch for switching the power supply 7 between an on state and an off state. When the power supply 7 is in the ON state, it supplies a current to the excitation light source 23 in the Q-switch laser oscillator head 21 to turn on the excitation light source 23. The semiconductor element 6 keeps the power supply 7 on while the input pulse signal 12 is at the high level,
Lights up. On the other hand, when the pulse signal 12 is at the low level, the power supply 7 is turned off. At this time, the excitation light source 23 is turned off without current flowing. In this example, the pulse signal 12 has a significant level when it is at a high level. Also, when the level is low, the level does not become significant.

The timing control circuit 4 generates a Q switch signal 13 in synchronization with the pulse signal 12,
Output to switch driver 5. Q switch signal 13
Is a pulse signal used for switching control between the ON state and the OFF state of the Q switch element 24. The Q switch driver 5 turns on the Q switch element 24 when the Q switch signal 13 is at a high level, and turns off the Q switch element 24 when the Q switch signal 13 is at a low level. The timing control circuit 4
When the laser rod 22 is excited, a Q-switch signal for switching the Q-switch element 24 from the OFF state to the ON state is generated. For example, the Q switch signal 13 is output in synchronization with the falling timing of the pulse signal 12 and the rising timing of the Q switch signal 13. In this example, the Q switch signal 13 is
It is a significant level when the level is high. Also, when the level is low, the level does not become significant.

The structure of the Q-switched laser oscillator head 21 is the same as that of the Q-switched laser controller controlled by the conventional Q-switched laser controller.
The configuration is the same as that of the switch laser oscillator head 21.
For example, a laser diode, a xenon lamp, or the like is used as the excitation light source 23, and emits light having a constant intensity when a current is applied. The laser rod 22 is formed by a laser medium, and while the excitation light source 23 is turned on,
The energy is stored to a high energy level. When the laser rod 22 is in the excited state, the Q switch element 24
Is turned on, the energy level of the laser rod 22 changes from a high level to a low level, and the laser rod 22
It emits light of a specific wavelength. As described above, the Q switch element 24 causes the laser rod 22 to emit light by being turned on. The total reflection mirror 25 and the emission mirror 26 forming the optical resonator generate stimulated emission by light having a specific wavelength emitted from the laser rod 22.
Part of the light emitted by the laser rod 22
6 and is emitted to the outside as laser light.

In the above embodiment, the repetitive signal generator is realized by the repetitive signal generator 2. The timing control means is realized by the timing control circuit 4. The excitation light source lighting control means is realized by the semiconductor element 6 and the power supply 7. The Q switch element driving means is realized by the Q switch driver 5.
The pulse width data holding means is realized by the pulse width setting circuit 3.

Next, the operation will be described. FIG. 2 is an explanatory diagram showing an example of a time chart of the pulse signal 11, the pulse signal 12, and the Q switch signal 13. FIG.
(A) shows an example of the waveform of the pulse signal 11 output from the repetitive signal generator 2. The time t0 is the generation cycle of the pulse signal 11, and is the reciprocal of the repetition frequency of the pulse signal 11.

When the pulse signal 11 is input from the repetitive signal generator 2, the timing control circuit 4 synchronizes the pulse signal 11 with the pulse signal 11 and
Output to FIG. 2B shows an example of the waveform of the pulse signal 12 output from the timing control circuit 4. In this example, the falling timing of the pulse signal 11 and the pulse signal 12
Is shown in which the pulse signals 11 and 12 are synchronized so that the rising timing of the pulse signals coincides with each other. Time t1 is the pulse width of the pulse signal 12. The pulse width setting circuit 3
The data of the pulse width (time t1) is held in advance, and the timing control circuit 4 determines the pulse width based on the data input from the pulse width setting circuit 3.

The semiconductor element 6 to which the pulse signal 12 has been input
Turns on the power supply 7 and turns on the excitation light source 23 when the pulse signal 12 is at the high level. When the pulse signal 12 goes low, the excitation light source 23 is turned off until it goes high again. As described above, the semiconductor element 6 and the power supply 7 repeatedly turn on the excitation light source 23 for the time t1 and then turn off the light. During the time t1 when the excitation light source 23 is turned on, the laser rod 22 is excited to a high energy level and stores energy.

The timing control circuit 4 outputs a Q switch signal 13 to the Q switch driver 5 in synchronization with the pulse signal 12. FIG. 2C shows an example of the waveform of the Q switch signal 13 output from the timing control circuit 4. This example shows a case where the pulse signal 12 and the Q switch signal 13 are synchronized so that the falling timing of the pulse signal 12 and the rising timing of the Q switch signal 13 match. The repetition frequency of the Q switch signal 13 and the pulse signal 11 are the same, and the generation cycle of the Q switch signal 13 is time t0.

The Q switch driver 5 turns on the Q switch element 24 when the Q switch signal 13 is at a high level. As shown in FIG. 2, the pulse signal 12 is output until the Q switch signal 13 becomes high level.
Is at a high level, so that the laser rod 22
Energy is stored during the time t1.
In this state, when the Q switch element 24 is turned on, the laser rod 22 emits light, and the laser light generated by the stimulated emission is emitted through the emission mirror 26 to the outside.

The Q switch repetition frequency (the repetition frequency of the ON state and the OFF state of the Q switch element 24) is the same as the repetition frequency of the pulse signal 11, and by changing the repetition frequency of the pulse signal 11,
The switch repetition frequency can be changed.

Even when the Q-switch repetition frequency changes, the light irradiation time on the laser rod 22 until the Q-switch element 24 is turned on is time t.
It is constant at 1. Further, the intensity of light from the excitation light source 23 is also constant. The energy level when the laser rod 22 is excited is proportional to the product of the light intensity of the excitation light source 23 and the irradiation time, but since the irradiation time t1 and the light intensity are constant, Q
There is no change in the energy level when the switch element 24 is turned on. For example, in the example shown in FIG. 2, even when the time t0 is increased and the Q-switch repetition frequency is lowered, the light irradiation time on the laser rod 22 is constant at the time t1. Conversely, even if the time t0 is shorter than the case shown in FIG. 2 and the Q-switch repetition frequency is increased, the light irradiation time is constant at the time t1 if t0> t1 is satisfied. It is.

Therefore, even if the Q switch repetition frequency is changed, the energy level of the excited laser rod 22 does not change, and the pulse width of the laser light and the peak value of the laser light energy can be kept constant. Then, if such a Q-switch laser control device 1 is applied to a trimmer device, even if the Q-switch repetition frequency is reduced, the substrate is not processed by excessive energy. Further, even if the Q-switch repetition frequency is increased, it is possible to prevent the processing time from being delayed due to heat accumulation.

Note that the generation period t0 of the pulse signal 11 is
When the pulse width becomes equal to or less than a predetermined pulse width (time t1), the pulse signal 12 becomes a continuous signal that maintains a high level. FIG.
4 shows an example of a time chart when the timing control circuit 4 outputs a continuous signal that maintains a high level to the semiconductor element 6. In this case, the timing control circuit 4 sets the Q switch signal 13 to the pulse signal 1 instead of the pulse signal 12.
Output in synchronization with 1. FIG. 3 shows an example in which the Q switch signal 13 and the pulse signal 11 are synchronized so that the falling timing of the pulse signal 11 and the rising timing of the Q switch signal 13 coincide.

In the state where t0 ≦ t1, the semiconductor device 6
, The semiconductor element 6 keeps the excitation light source 23 turned on. Therefore, Q
When the switch repetition frequency is changed (when the time t0 is changed), the irradiation time on the laser rod 22 until the Q switch element 24 is turned on changes, so that the pulse width of the generated laser light and the laser light The peak value of the energy will also fluctuate. However, t0> t1
In such a state, such a change does not occur, so that the change in the pulse width and peak value of the laser light can be suppressed as a whole.

FIG. 4 is a graph showing a change in the pulse width of the laser beam when the Q-switch repetition frequency is changed. A graph L0 shown in FIG. 4 shows a change in the pulse width of the laser light when the conventional Q-switched laser control device is used. The graphs L1, L2, and L3 show the pulse signal 1 previously held by the pulse width setting circuit 3 in the present invention.
The data of the pulse width (time t1) of 2
The change in the pulse width of the laser light when μs and 33 μs are shown. The pulse width of 67 μs, 50 μs, and 33 μs is
The repetition frequency of the pulse signal 12 is 15 kHz,
It corresponds to 20 kHz and 30 kHz.

When a conventional Q-switch laser controller is used, the pulse width of the laser beam increases with the Q-switch repetition frequency as shown in graph L0. However, according to the present invention, as shown in the graphs L1, L2, and L3, the pulse width of the laser light can be kept constant in a region lower than the repetition frequency of the pulse signal 12. Q
As the switch repetition frequency increases, the pulse width of the laser beam increases, but fluctuations in the pulse width can be suppressed as a whole.

FIG. 5 is a graph showing a change in the peak value of the laser light energy when the Q-switch repetition frequency is changed. A graph L0 shown in FIG. 5 shows a change in the peak value when a conventional Q-switched laser control device is used. Graphs L1, L2, and L3 show the pulse width setting circuit 3 according to the present invention, similarly to the case shown in FIG.
Is the pulse width of the pulse signal 12 previously held (time t1)
The change of the peak value when the data of No. is 67 μs, 50 μs, and 33 μs is shown. The pulse widths of the pulse signal 12 are 15 kHz and 20 kHz, respectively.
z, 30 kHz.

When the conventional Q-switch laser controller is used, the peak value decreases as the Q-switch repetition frequency increases, as shown in graph L0. However, according to the present invention, as shown in the graphs L1, L2, and L3, the peak value can be kept constant in a region lower than the repetition frequency of the pulse signal 12. As the Q-switch repetition frequency increases, the peak value decreases, but fluctuations in the peak value can be suppressed as a whole.

Note that the rising timing of the pulse signal 12 is not limited to the above example, and may be any timing as long as it is synchronized with the pulse signal 11. In the above example, the case where the pulse signal 12 rises at the falling timing of the pulse signal 11 has been described. However, the pulse signal 12 may rise at the rising timing of the pulse signal 11, for example.

Similarly, the rising timing of the Q switch signal 13 is not limited to the above example. The timing control circuit 4 may output the Q switch signal 13 for switching the Q switch element 24 from the off state to the on state when the laser rod 22 is excited, in synchronization with the pulse signal 12. In the above example, the case where the Q switch signal 13 rises at the timing of the fall of the pulse signal 12 has been described. For example, the Q switch signal 13 rises after a predetermined time has elapsed after the fall of the pulse signal 12. Is also good. The laser rod 22 maintains a high energy level for a certain time even when the excitation light source 23 is turned off. Therefore, even if the Q switch signal 13 rises with a predetermined time delay from the fall timing of the pulse signal 12, laser light can be generated by stimulated radiation.

[0040]

According to the present invention, a repetitive signal generating means for generating a first pulse signal, and a second pulse signal having a predetermined pulse width in synchronization with the first pulse signal are generated. Timing control means for generating a Q-switch signal used for switching control between the ON state and the OFF state of the switch element in synchronization with the second pulse signal; and an excitation light source for a Q-switch laser oscillator based on the second pulse signal And a Q-switch element driving means for switching between an on-state and an off-state of the Q-switch element based on the Q-switch signal. Therefore, when the generation cycle of the first pulse signal is longer than the predetermined pulse width of the second pulse signal, the pulse width of the laser light and the energy of the laser light It is possible to maintain the peak value constant.
Therefore, fluctuations in the pulse width and peak value of the laser light can be suppressed as a whole. Further, when performing laser processing, the processing time is not delayed due to fluctuations in the pulse width of laser light and the peak value of laser light energy, and the workpiece is not processed more than necessary.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing one embodiment of a Q-switch laser control device according to the present invention.

FIG. 2 is an explanatory diagram showing an example of a time chart of each signal.

FIG. 3 is an explanatory diagram showing an example of a time chart of each signal.

FIG. 4 is a graph showing a change in pulse width of laser light when a Q-switch repetition frequency is changed.

FIG. 5 is a graph showing a change in a peak value of laser light energy when a Q-switch repetition frequency is changed.

FIG. 6 is an explanatory diagram showing an embodiment of a conventional Q-switch laser control device.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 Q switch laser controller 2 repetitive signal generator 3 pulse width setting circuit 4 timing control circuit 5 Q switch driver 6 semiconductor element 7 power supply 11, 12 pulse signal 13 Q switch signal 21 Q switch laser oscillator head (Q switch laser oscillator) Reference Signs List 22 laser rod 23 excitation light source 24 Q switch element 25 total reflection mirror 26 emission mirror

Claims (6)

[Claims] 1. A Q-switch laser control device for controlling a Q-switch laser oscillator having a Q-switch element, comprising: a repetitive signal generating means for generating a first pulse signal; Timing control means for generating a second pulse signal with a predetermined pulse width, and generating a Q switch signal used for switching on and off states of the Q switch element in synchronization with the second pulse signal. An excitation light source lighting control means for causing an excitation light source of the Q-switched laser oscillator to repeatedly turn on and off for a predetermined time based on the second pulse signal; and turning on the Q-switch element based on the Q-switch signal. A Q-switch laser control device comprising: Q-switch element driving means for switching between a state and an OFF state. 2. The excitation light source lighting control means includes a power supply for turning on the excitation light source, and a semiconductor element for switching the power supply between an on state and an off state, wherein the semiconductor element is a second element generated by the timing control means. By turning on the power when the pulse signal is at a significant level and turning off the power when the second pulse signal is not at a significant level, the excitation light source can be turned on and off for a predetermined time. 2. The Q-switch laser control device according to claim 1, wherein 3. The Q-switch laser control device according to claim 1, wherein the timing control means generates a Q-switch signal for switching the Q-switch element from an off state to an on state when the laser medium is excited. . 4. The Q switch according to claim 3, wherein the timing control means switches the Q switch signal from a non-significant level to a significant level near a timing for switching the second pulse signal from a significant level to a non-significant level. Laser control device. 5. A pulse width data holding means for holding data of a predetermined pulse width of the second pulse signal, wherein the timing control means has a pulse width corresponding to the data held by the pulse width data holding means. The Q-switch laser control device according to any one of claims 1 to 4, wherein the pulse signal is generated as follows. 6. A Q-switched laser oscillator comprising: an excitation light source for exciting a laser medium; a Q-switch element for emitting light to the excited laser medium by being turned on; and controlling the Q-switched laser oscillator. A repetitive signal generating means for generating a first pulse signal; and a predetermined pulse width synchronized with the first pulse signal. A timing control means for generating a second pulse signal in synchronism with the second pulse signal and generating a Q switch signal used for switching control of the ON state and the OFF state of the Q switch element; Excitation that causes the excitation light source of the Q-switched laser oscillator to turn on and off for a predetermined time based on a pulse signal A laser device comprising: a light source lighting control unit; and a Q switch element driving unit that switches an ON state and an OFF state of the Q switch element based on the Q switch signal.