WO2017146331A1

WO2017146331A1 - Laser device and laser generation method

Info

Publication number: WO2017146331A1
Application number: PCT/KR2016/010236
Authority: WO
Inventors: 이경구; 이재열; 신선호
Original assignee: (주)이오테크닉스
Priority date: 2016-02-25
Filing date: 2016-09-12
Publication date: 2017-08-31
Also published as: TW201742342A; KR101787526B1; TWI648931B; KR20170100361A

Abstract

According to exemplary embodiments, a laser device and a laser generation method are provided. The laser device according to an embodiment generates a trigger signal from a laser modulation signal. In addition, the laser device emits pumping light at a gain medium by synchronizing an optical pumping device by means of the trigger signal.

Description

Laser device and laser generation method

The present invention relates to a laser device and a laser generating method using the laser device. The present invention relates to a technology for generating laser light by supplying pumping light to the gain medium so that the gain medium of the laser device is not damaged.

In general, the laser processing process refers to a process of processing the shape or physical properties of the surface of the object by scanning the laser light on the surface of the object to be processed. There may be various examples of the object to be processed, the shape is a 2 D plane It may be shaped. Examples of the laser processing process include patterning to form a pattern on the surface of the object, a process of modifying the physical properties of the object, a process of heating the object and deforming the shape of the object by using a laser, and a process using laser light. There may be a process of cutting the object.

LASER devices are mechanical devices made to generate laser light using a simulated emission phenomenon. The laser uses a main resonator to induce the emission of light so that the beam is emitted with coherence. Due to the monochromatic and coherent characteristics of the laser, laser devices are effectively used throughout the industry, including in the manufacturing process, in addition to the precise cutting of the skin during surgical operations or the selective removal of parts of body tissue. It is also widely used as a medical device that plays a role.

The laser device may generate laser light using only the above-described main resonator, but amplifies the energy of the laser light by using a gain medium in order to emit high intensity laser light. The laser device injects excitation energy into the gain medium through an optical pumping action. The electrons inside the gain medium are then excited by the light pumping action to produce laser light.

However, an exothermic phenomenon may occur in the gain medium in the process of optically pumping the gain medium. In addition, when more energy is injected into the gain medium than the allowable value, the gain medium burns and is damaged.

The gain medium is used to generate laser light to prevent the gain medium from being damaged by high temperatures.

In one aspect,

A laser modulated signal generator for generating a laser modulated signal;

A first trigger signal generator for receiving the laser modulated signal and generating a first trigger signal;

A second trigger signal generator for receiving the laser modulated signal and generating a second trigger signal;

A seed laser generator synchronized with the first trigger signal to emit seed laser light to a gain medium; And

And an optical pumping device synchronized with the second trigger signal to emit pumping light to the gain medium.

According to exemplary embodiments, the optical pumping device may be synchronized with the trigger signal to emit the pumping light to the gain medium. This can prevent excessive energy from being stored in the gain medium. In addition, the power consumption of the optical pumping apparatus can be reduced.

1 is a view showing a laser device according to a comparative example.

2 is a view showing a change in the amount of energy inside the gain medium when the seed laser light is generated aperiodically in the laser device according to the comparative example.

3 is a diagram illustrating a laser device according to an exemplary embodiment.

4 is a diagram illustrating a laser modulation signal, a first trigger signal and a second trigger signal by way of example.

5 is a diagram exemplarily illustrating a laser modulated signal, a first trigger signal, and a second trigger signal.

6 and 7 exemplarily illustrate output power of a laser modulated signal, seed laser light, and output power of pumped light.

8 is a graph showing a change in the amount of energy stored in the gain medium and a change in the optical power of the output laser as the seed laser light and the pumping light are emitted as shown in FIG. 6.

9 is a diagram illustrating a case in which the seed laser light is emitted aperiodically.

10 is a flowchart illustrating a laser generation method using the laser apparatus described with reference to FIGS. 3 to 9.

In one aspect,

A laser modulated signal generator for generating a laser modulated signal;

The optical pumping device may include a laser diode.

The optical pumping apparatus may further include a current supply unit supplying a current to the laser diode, and the current supply unit may be synchronized with the second trigger signal to change a current level.

The second trigger signal generator may generate the second trigger signal after receiving a predetermined delay time after receiving the laser modulated signal.

The first trigger signal generator receives the laser modulated signal and after the first delay time passes, generates the first trigger signal, and the second trigger signal generator receives the laser modulated signal and the second delay time occurs. After that, generating the second trigger signal,

The second delay time may be greater than the first delay time.

The optical pumping device may emit the pumping light as an impulse light.

The pulse width of the impulse light may depend on a predetermined amplification ratio of the seed laser light.

The optical pumping device may allow the emission of the impulse light to be terminated at any point in a time period in which the intensity of the seed laser light is maximum from just before generation of the seed laser light having the maximum intensity of the seed laser light is generated.

In another aspect,

Generating a laser modulated signal;

Generating a first trigger signal from the laser modulated signal;

Generating a second trigger signal from the laser modulated signal;

Emitting seed laser light to a gain medium in synchronization with the first trigger signal;

And emitting pumped light to the gain medium in synchronization with the second trigger signal.

Emitting the pumping light to the gain medium,

The current level supplied to the laser diode may be changed by the second trigger signal.

The generating of the second trigger signal may generate the second trigger signal after receiving a predetermined delay time after receiving the laser modulated signal.

The generating of the first trigger signal may include generating the first trigger signal after receiving the laser modulated signal and passing a first delay time, and generating the second trigger signal may receive the laser modulated signal. And after the second delay time passes, generating the second trigger signal.

The second delay time may be greater than the first delay time.

The emitting of the pumping light to the gain medium may emit the pumping light as impulse light.

The pulse width of the impulse light may depend on the amplification ratio of the preset seed laser light.

The emitting of the pumping light to the gain medium may include the emission of the impulse light at any point in time at which the intensity of the seed laser light is maximum from just before the generation of the seed laser light is the maximum intensity of the seed laser light. You can make it bell.

In the drawings, like reference numerals refer to like elements, and the size of each element in the drawings may be exaggerated for clarity and convenience of description. Meanwhile, the embodiments described below are merely exemplary, and various modifications are possible from these embodiments.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are only used to distinguish one component from another.

Singular expressions include plural expressions unless the context clearly indicates otherwise. In addition, when a part is said to "include" a certain component, which means that it may further include other components, except to exclude other components unless otherwise stated.

In addition, terms, such as "... part", "module", etc. described in the specification mean a unit that processes at least one function or operation.

1 is a view showing a laser device according to a comparative example.

Referring to FIG. 1, a laser apparatus according to a comparative example may include a seed laser generator 10 generating a seed laser. The seed laser generator 10 may generate a laser light pulse. The seed laser generator 10 may transmit the laser light pulse to the gain medium 20 through the optical fiber 22.

The laser device according to the comparative example may include an optical pumping device 30 for supplying energy to the gain medium 20. The optical pumping device 30 may increase the amount of energy stored in the gain medium 20 by irradiating light onto the gain medium 20. The gain medium 20 may amplify the seed laser light received from the seed laser generator 10. The gain medium 20 may emit an output optical signal S2 having the same shape as the seed laser optical signal S1 by amplifying the seed laser optical signal S1.

According to a comparative example, the optical pumping device 30 may continuously emit the pumping light of a constant intensity to the gain medium 20. Therefore, as the time for the optical pumping device 30 to emit the pumping light to the gain medium 20 increases, the amount of energy stored in the gain medium 20 may increase. When the seed laser light is irradiated onto the gain medium 20, the gain medium 20 may amplify the seed laser light using energy stored in the gain medium 20 to emit the seed laser light as the output laser light.

When the gain medium 20 emits output laser light, energy stored in the gain medium 20 may be emitted to the outside. Therefore, when the seed laser light is irradiated to the gain medium 20 in a periodic pulse shape, the amount of energy stored in the gain medium 20 may also be repeated to increase and decrease periodically. However, when the seed laser light is irradiated to the gain medium 20 aperiodically, excessive energy may be supplied to the gain medium 20 in a section in which the seed laser light irradiation time interval is long.

2 is a view showing a change in the amount of energy inside the gain medium 20 when the seed laser light is generated aperiodically in the laser device according to the comparative example.

In FIG. 2, the graph (a) is a graph showing a change with time of the output power of the seed laser light emitted from the seed laser generator 10. In addition, (b) the graph is a graph showing the change over time of the output power of the pumping light emitted by the optical pumping device 30 to the gain medium 20. In addition, (c) graph is a graph showing the change over time of the amount of energy stored in the gain medium (20).

Referring to FIG. 2, the optical pumping apparatus 30 may emit pumping light of a constant intensity to the gain medium 20. In this case, the output power of the output laser light emitted from the gain medium 20 can be adjusted by adjusting the intensity of the pumping light. Referring to the graph (c), the amount of energy stored in the gain medium 20 may increase as the pumped light is irradiated onto the gain medium 20. When the seed laser light is incident on the gain medium 20, the amount of energy stored in the gain medium 20 may be drastically reduced while the output laser light is emitted from the gain medium 20.

While the seed laser light is periodically incident on the gain medium 20, the amount of energy stored in the gain medium 20 may also increase and decrease periodically. Therefore, the amount of energy stored in the gain medium 20 may not increase by a certain amount or more. However, in the period where the seed laser light is incident on the gain medium 20 aperiodically, the amount of energy stored in the gain medium 20 may be continuously increased during the time when the seed laser light is not incident. In addition, when the time for which the seed laser light is not emitted becomes long, the amount of energy stored in the gain medium 20 may be excessively high.

If the amount of energy stored in the gain medium 20 is excessively high, the gain medium 20 may be damaged by overheating. For example, if the amount of energy stored in the gain medium 20 is higher than the allowable value, stimulated Brillouin scattering may occur in the gain medium 20. That is, while the incident light and the scattered light are nonlinearly coupled inside the gain medium 20, they may be amplified to cause a high temperature phenomenon of the gain medium 20.

3 is a diagram illustrating a laser device 100 according to an exemplary embodiment.

Referring to FIG. 3, a laser device 100 according to an exemplary embodiment may include a laser modulated signal generator 110 generating a laser modulated signal and a first trigger receiving a laser modulated signal to generate a first trigger signal. Seed laser generation, a second trigger signal generator 132 for receiving a laser modulated signal and generating a second trigger signal, and seed laser generation synchronized with the first trigger signal to emit seed laser light to a gain medium. Device 124 and an optical pumping device 134 synchronized with the second trigger signal to emit pumping light to the gain medium.

The laser modulated signal generator 110 may generate a predetermined pulse signal as a laser modulated signal. The laser modulated signal can be generated periodically or aperiodically. The laser modulation signal of the laser modulation signal generator 110 may be a signal for causing the laser device 100 to output laser light.

The first trigger signal generator 122 may receive a laser modulated signal from the laser modulated signal generator. When the first trigger signal generator 122 receives the laser modulated signal, the first trigger signal generator 122 may generate the first trigger signal. The first trigger signal generator 122 may transmit the first trigger signal to the seed laser generator 124. The seed laser generator 124 may be synchronized by the first trigger signal. Synchronization of the seed laser generator 124 means that the operating state of the seed laser generator 124 is changed. When the seed laser generator 124 is synchronized by the first trigger signal, the operating state is changed. Seed laser light may be emitted to the outside.

The second trigger signal generator 132 may receive a laser modulated signal from the laser modulated signal generator. When the second trigger signal generator 132 receives the laser modulated signal, the second trigger signal generator 132 may generate a second trigger signal. The second trigger signal generator 132 may transmit a second trigger signal to the optical pumping device 134. The optical pumping device 134 may be synchronized by the second trigger signal. Synchronization of the optical pumping device 134 means that the operating state of the optical pumping device 134 is changed.

For example, the optical pumping device 134 may include a laser diode 134b and a current supply unit 134a for supplying current to the laser diode 134b. The current supply unit 134a of the optical pumping device 134 may change the current level supplied to the laser diode 134b in synchronization with the second trigger signal. As the current supply unit 134a changes the current level supplied to the laser diode 134b, the light energy emitted by the laser diode 134b to the gain medium 138 may vary.

The seed laser device 124 may emit seed laser light in the gain medium 138 in synchronization with the first trigger signal. The seed laser device 124 may include a main resonator therein. The seed laser device 124 induces and emits light by the main resonator, and thus may emit laser light matching the coherence as the seed laser light. The intensity of the seed laser light emitted from the seed laser device 124 may have a pulse shape. Seed laser light may be emitted periodically or aperiodically.

The gain medium 138 may illustratively include active ions obtained from rare earth elements such as ytterbium (Yb), neodymium (Nd), erbium (Er), thulium (Tm), and the like. Also, gain medium 138 may include active ions obtained from transition metal elements such as chromium (Cr), titanium (Ti), and the like.

From active ions obtained from rare earth elements such as ytterbium (Yb), neodymium (Nd), erbium (Er), thulium (Tm), or transition metal elements such as chromium (Cr) and titanium (Ti) The gain medium 138 may be in the doped state by the obtained active ions. The gain medium 138 may amplify the seed laser light using the energy supplied from the optical pumping device 134 and emit the seed laser light as output laser light.

The optical pumping device 134 may emit pumped light in the gain medium 138 in synchronization with the second trigger signal. The amount of energy supplied by the optical pumping device 134 to the gain medium 138 may be determined by the time for irradiating the pumping light. The optical pumping device 134 may emit the pumping light to the gain medium 138 in the form of a single pulse every time the second trigger signal is detected. That is, the optical pumping device 134 may emit impulse light to the gain medium 138 whenever the second trigger signal is detected. The time interval at which the optical pumping device 134 emits impulse light may depend on the time interval at which the second trigger signal is generated. In addition, the pulse width of the impulse light emitted by the optical pumping device 134 may depend on the output power of the preset output laser light. For example, when the amplification ratio between the seed laser light and the output laser light is large, the pulse width of the impulse light may be relatively large. On the other hand, when the amplification ratio between the seed laser light and the output laser light is small, the pulse width of the impulse light may be relatively small.

In Figure 4 (a) graph is a graph showing the change in intensity of the laser modulation signal generated by the laser modulation signal generator 110 over time. Also, (b) the graph is a graph showing the change in intensity of the first trigger signal over time. In addition, (c) the graph is a graph showing the change in intensity over time of the second trigger signal.

Referring to FIG. 4, when a laser modulated signal is generated, first and second trigger signals may be generated correspondingly. The first and second trigger signals may be electrical pulse signals. The first and second

trigger signal generators

122 and 132 may extract the trigger from the laser modulated signal to generate the first and second trigger signals, respectively. The pulse widths of the first and second trigger signals may be narrower than the pulse widths of the laser modulated signals.

After detecting the laser modulation signal, the first trigger signal generator 122 may generate the first trigger signal after a predetermined delay time d elapses. On the other hand, the second trigger signal generator 132 may generate the second trigger signal immediately upon detecting the laser modulated signal. Thus, the first trigger signal may be delayed than the second trigger signal.

When the first trigger signal is delayed than the second trigger signal, the seed laser light may be delayed and emitted than the pumping laser light. If the seed laser light emits more delayed than the pumped laser light, energy may be stored in the gain medium 138 by the pumping light before the seed laser light is emitted. The gain medium 138 may amplify the seed laser light using energy stored by the pumping light until the seed laser light is emitted. The rate at which the seed laser light is amplified may depend on the amount of energy stored in the gain medium 138. In addition, the amount of energy stored in gain medium 138 may depend on the time that pumped light is emitted to gain medium 138 before the seed laser light is incident on gain medium 138. And, depending on the pumping light irradiation time required for seed laser light amplification. Accordingly, the delay time until the first trigger signal generator 122 detects the laser modulated signal and generates the first trigger signal may depend on the pumping light irradiation time required for the seed laser light amplification. In addition, the delay time until the first trigger signal generator 122 detects the laser modulated signal and generates the first trigger signal may be changed according to the pulse width of the pumping light.

In Figure 5 (a) graph is a graph showing the change in intensity of the laser modulation signal generated by the laser modulation signal generator 110 over time. Also, (b) the graph is a graph showing the change in intensity of the first trigger signal over time. In addition, (c) the graph is a graph showing the change in intensity over time of the second trigger signal.

Referring to FIG. 5, when a laser modulated signal is generated, first and second trigger signals may be generated correspondingly. The first and second trigger signals may be electrical pulse signals.

After detecting the laser modulation signal, the first trigger signal generator 122 may generate the first trigger signal after the first delay time d1 elapses. On the other hand, the second trigger signal generator 132 may generate the second trigger signal after the second delay time d2 has elapsed after detecting the laser modulated signal. The first delay time d1 may be greater than the second delay time d2. Thus, the first trigger signal may be delayed than the second trigger signal.

The rate at which the seed laser light is amplified may depend on the amount of energy stored in the gain medium 138. In addition, the amount of energy stored in gain medium 138 may depend on the time that pumped light is emitted to gain medium 138 before the seed laser light is incident on gain medium 138. Thus, the difference between the first delay time d1 and the second delay time d2 may depend on the pumping light irradiation time required for the seed laser light amplification. In addition, the difference between the first delay time d1 and the second delay time d2 may be changed according to the pulse width of the pumping light.

6 and 7 exemplarily illustrate output power of a laser modulation signal, seed laser light, and output power of pumped light.

6 and 7 (a) graph is a graph showing the change in intensity of the laser modulation signal generated by the laser modulation signal generator 110 over time. In addition, (b) graph is a graph showing the output power change with time of the seed laser light emitted from the seed laser light generator. In addition, (c) graph is a graph showing the output power change with time of the pumping light emitted from the optical pumping device 134.

Referring to FIG. 6, the seed laser light may be emitted more delayed than the pumped light. In addition, the pumping light and the seed laser light may be emitted in the form of an impulse each time a laser modulation signal is generated. The pumping light can be terminated at the point where the intensity of the seed laser light is maximized. As another example, referring to FIG. 7, the pumping light may be terminated immediately before the seed laser light is generated.

That is, the pumping light may be emitted only until one point of time period in which the intensity of the laser light is maximized before the seed laser light is emitted. For example, the pumping light may be terminated when the intensity of the seed laser light is maximized or immediately before the seed laser light is emitted. If the pumping light is emitted only up to the time period described above, all of the energy of the pumping light can be used to amplify the seed laser light. Thus, after the seed laser light is amplified and output, it is possible to prevent unnecessary energy from remaining in the gain medium 138. In addition, the energy consumption supplied to the gain medium 138 can also be reduced.

The timing at which the pumping light is terminated and the timing at which the emission of the seed laser light is started or maximized may be the same by adjusting the pulse width of the pumping light and the time difference at which the first and second trigger signals are generated. By allowing the pumped light to be emitted only until the start or maximum of the seed laser light is emitted, the rate of energy stored in the gain medium 138 can be used to amplify the seed laser light. In addition, the power required to emit the pumping light can be reduced.

FIG. 8 is a graph showing a change in the amount of energy stored in the gain medium and a change in the optical power of the output laser as the seed laser light and the pumping light are emitted as shown in FIG. 6.

In Figure 8 (a) is a graph showing the output power change with time of the seed laser light. In addition, (b) graph is a graph showing the output power change with time of the pumping light. Also, (c) graph is a graph showing the change over time of the amount of energy stored in the gain medium 138. In addition, (d) graph is a graph showing the output power change with time of the output laser light.

Referring to FIG. 8, the amount of energy stored in the gain medium 138 may increase while pumping light is emitted. When the seed laser light is emitted, the amount of energy stored in the gain medium may be reduced while the output laser light is emitted from the gain medium 138. Since the seed laser light and the pumping light are emitted in synchronization, the amount of energy stored in the gain medium may not exceed the allowable value. In addition, since the pumping light is emitted before the seed laser light is emitted, energy for amplification may be stored in the gain medium 138 when the seed laser light is emitted. In addition, since the pumping light is not emitted after the seed laser light is emitted, unnecessary energy may be prevented from accumulating in the gain medium 138.

In Figure 9 (a) graph is a graph showing the output power change with time of the seed laser light. In addition, (b) graph is a graph showing the output power change with time of the pumping light. Also, (c) graph is a graph showing the change over time of the amount of energy stored in the gain medium 138. In addition, (d) graph is a graph showing the output power change with time of the output laser light.

Referring to FIG. 9, the pumping light may not be emitted in a section in which the seed laser light is not emitted. In the case of FIG. 2, when the pumping light is constantly emitted, if the seed laser light is emitted aperiodically, the energy stored in the gain medium 138 may be excessive, resulting in damage to the gain medium 138. However, in the case of FIG. 8, since the pumping light is also emitted in synchronization with the second trigger signal, the pumping light may not be emitted in a time period in which the seed laser light is not emitted. In addition, the amplification ratio of the seed laser light can be determined by the pulse width of the pumping light. Therefore, the amount of energy stored in the gain medium 138 can be prevented from becoming excessive.

10 is a flowchart illustrating a laser generation method using the laser apparatus 100 described with reference to FIGS. 3 to 9.

In the description of the embodiment of FIG. 10, the content overlapping with those of FIGS. 3 to 9 will be omitted.

Referring to FIG. 10, according to an exemplary embodiment, a method of generating a laser may include generating a laser modulated signal 1110, generating a first trigger signal from a laser modulated signal 1120, and generating a second from a laser modulated signal. Generating a trigger signal (1130), synchronizing by a first trigger signal to emit a seed laser light to a gain medium (138), and synchronizing by a second trigger signal to pump pumped light to the gain medium ( 138).

In operation 1110, the laser modulated signal generator 110 may generate a laser modulated signal. The laser modulated signal can be generated periodically or aperiodically with a predetermined pulse signal.

In operation 1120, the first trigger signal generator 122 may receive a laser modulated signal and generate a first trigger signal. The first trigger signal may synchronize the seed laser generator 124.

In operation 1130, the second trigger signal generator 132 may receive a laser modulated signal and generate a second trigger signal. The second trigger signal may synchronize the optical pumping device 134.

Each of the first trigger signal and the second trigger signal may be generated after a different delay time elapses after the laser modulation signal is generated. For example, the first trigger signal may be delayed than the second trigger signal. The seed laser light may be delayed than the pumping light and emitted.

In operation 1140, the seed laser light generating device 124 may emit seed laser light in the gain medium 138. Further, in step 1150, the optical pumping device 134 may emit pumping light to the gain medium 138. The time point at which the seed laser light and the pumping light are emitted may be determined by generating time points of the first and second trigger signals, respectively.

The optical pumping device 134 may emit the pumping light to the gain medium 138 as the impulse light each time the second trigger signal is received. The pulse width of the impulse light may depend on the amplification ratio of the preset seed laser light. In operation 1140, the optical pumping device 134 may terminate the emission of the pumping light emitted as the impulse light when the intensity of the seed laser light is maximum. As described above, by controlling the emission of the pumping light, it is possible to reduce the power consumption of the pumping light and to efficiently manage the energy stored in the gain medium 138.

In the above, the laser generating method using the laser device and the laser device according to the comparative example and the exemplary embodiment have been described with reference to FIGS. 1 to 10. According to embodiments, the optical pumping device 134 may be synchronized with the trigger signal to emit the pumping light to the gain medium 138. This may prevent excessive energy from being stored in the gain medium 138. In addition, the power consumption of the optical pumping device 134 can be reduced.

While many details are set forth in the foregoing description, they should be construed as illustrative of preferred embodiments rather than to limit the scope of the invention. Therefore, the scope of the present invention should not be defined by the described embodiments, but should be defined by the technical spirit described in the claims.

Claims

A laser modulated signal generator for generating a laser modulated signal;

A first trigger signal generator for receiving the laser modulated signal and generating a first trigger signal;

A second trigger signal generator for receiving the laser modulated signal and generating a second trigger signal;

A seed laser generator configured to emit seed laser light to a gain medium in synchronization with the first trigger signal; And

And an optical pumping device synchronized with the second trigger signal to emit pumping light to the gain medium.
The method of claim 1,

The optical pumping device comprises a laser diode.
The method of claim 2,

The optical pumping device further comprises a current supply unit for supplying a current to the laser diode, the current supply unit is a laser device that is synchronized by the second trigger signal to change the current level.
The method of claim 1,

And the second trigger signal generator generates the second trigger signal after receiving a predetermined delay time after receiving the laser modulated signal.
The method of claim 1,

The first trigger signal generator receives the laser modulated signal and after the first delay time passes, generates the first trigger signal, and the second trigger signal generator receives the laser modulated signal and the second delay time occurs. After that, generating the second trigger signal,

And the second delay time is greater than the first delay time.
The method of claim 1,

The optical pumping device, the laser device for emitting the pumping light as an impulse light.
The method of claim 6,

And a pulse width of the impulse light depends on a predetermined amplification ratio of the seed laser light.
The method of claim 6,

The optical pumping device, the laser device to terminate the emission of the impulse light at any point in the time interval when the intensity of the seed laser light is maximized immediately before the seed laser light is generated.
Generating a laser modulated signal;

Generating a first trigger signal from the laser modulated signal;

Generating a second trigger signal from the laser modulated signal;

Emitting seed laser light to a gain medium in synchronization with the first trigger signal;

Emitting a pumping light to the gain medium in synchronization with the second trigger signal.
The method of claim 9,

Emitting the pumping light to the gain medium,

And a current level supplied to the laser diode by the second trigger signal.
The method of claim 9,

The generating of the second trigger signal may include generating the second trigger signal after receiving a predetermined delay time after receiving the laser modulated signal.
The method of claim 9,

The generating of the first trigger signal may include generating the first trigger signal after receiving the laser modulated signal and passing a first delay time, and generating the second trigger signal may receive the laser modulated signal. And after the second delay time passes, generating the second trigger signal.

And the second delay time is greater than the first delay time.
The method of claim 9,

And emitting the pumping light to the gain medium, emits the pumping light as impulse light.
The method of claim 13,

The pulse width of the impulse light is dependent on the amplification ratio of the predetermined seed laser light.
The method of claim 13,

The step of emitting the pumped light to the gain medium, the laser device to terminate the emission of the impulse light at any point in the time interval of the maximum intensity of the seed laser light from immediately before the seed laser light is generated.