KR102004169B1 - Medical multi-laser amplification output device - Google Patents

Abstract

The present invention relates to a medical multi-laser amplification output apparatus, comprising: a light resonance section composed of a plurality of laser cavities; and an optical system for guiding light sequentially output from the plurality of laser cavities in a single path to form a single output laser; A processor unit for determining energy to excite a medium of the laser cavity and controlling the optical resonator unit; And a cooling unit for controlling the temperature of the optical resonator unit. In the process of controlling the initial pulse of the laser cavity, the processor unit applies an offset signal having a gradually increasing pulse width to reach a set output value of the laser cavity And adjusting the offset of the light resonance part by fixing the pulse width of the offset signal.

Description

[0001] MEDICAL MULTI-LASER AMPLIFICATION OUTPUT DEVICE [0002]

The present invention relates to a medical multi-laser amplification output device for amplifying a laser output with a plurality of laser cavities and outputting a laser beam capable of hemostasis at the time of incision.

Laser that is recognized as a fundamental tool in the medical treatment is based on a variety of wavelength (Wavelength) and high energy density (Fluence), and behavior Femto ^(10-15) second hundred millimeters from a short pulse during the ^(10-3) seconds , Which can be used to selectively treat pigment lesions and vascular lesions, has been actively applied in medical applications. According to the wavelength and energy characteristics, the laser can be an argon laser for incineration of human tissue, a helium neon laser for laser acupuncture or blood velocity measurement that can be identified by eyes, a CO ₂ laser using properties such as a knife- And a YAG laser used for treatment by using an incision property.

Surgical laser is inserted into the human body through a very narrow hole and connected with an optical fiber or a small endoscopic camera, compared with a surgical field requiring a large field of view to perform mechanical surgery. . Examples of applications include prostate surgery, laryngoscope surgery, heart laser surgery, and disk surgery. Surgical laser equipment has been actively applied in all medical fields due to the spread of minimally invasive procedures and researches have been actively conducted to improve laser equipment with shorter pulse and higher output.

As an example of a surgical laser applied to prostate surgery, an Andy-Yag (Nd: YAG) laser has been mainly used. The Andy Yag laser is a low-power system, so the power of the laser is so weak that it does not vaporize unnecessary tissues. When laser is applied to the prostate tissue, normal tissues around the tissue are burned or puffed. The Andy Yag laser was treated with a pelvic urine for more than two weeks because of the swollen prostate after the procedure. Then, KTP laser technique was introduced. The KTP laser has the advantage of being able to precisely target and burn out only the enlarged prostate with a powerful, high power method. However, KTP lasers were also limited when prostate tissue became extremely hypertrophic. In recent years, prostate treatment using a holmium laser having a wavelength of about 2100 nm (HoLEP technique) has been attracting attention as an advanced technique. The holmium laser inserts the instrument through the urethra and then rips the tissue out from the inside to the outside. The holmium laser has the advantage of being able to completely remove the enlarged prostate tissue with fewer side effects than the conventional laser technique of destroying the tissue.

This specification discloses a multi-laser amplification output device applicable to the aforementioned treatment laser, in particular, to an holmium laser device. Medical laser equipment uses optical pumping means to excite a solid state gain medium into a laser state. For example, the gain medium may be a cylindrical laser rod and the optical pumping means may be a longitudinally extending flash lamp positioned parallel to the rod. Most gain media must be maintained at a high temperature during the lasing operation. However, Ho: YAG (holmium yag) or Ho: YLF materials and other Holmium doped gain media are preferably maintained at low temperatures during the lasing operation. Since most optical pumping means increase the temperature to a high level, the laser system requires a cooling system and must maintain a range of approximately + 10 ° to -10 ° C.

U.S. Patent No. 9939631 (hereinafter abbreviated as "prior patent") discloses an apparatus having a plurality of laser cavities that are sequentially pumped. The foregoing prior patent discloses a control arrangement for controlling the output laser of a plurality of laser cavities to the center point of the servo mirror.

Surgical laser instruments used in medical applications require a high degree of precision in the process of forming the output laser systematically. A great sensitivity is required for the arrangement, angle, and curvature of the optical system mirror for laser focusing, and adjustment of the offset is also a very difficult technical problem because of the characteristics of the light resonance portion having the multi-channel laser cavity. In addition, the temperature control of the laser cavity also affects the performance of the laser and, unlike conventional gain media, which are maintained at high temperatures, the holmium laser equipment must have a proper cooling system for low temperature maintenance. In addition, due to the nature of the medical equipment, the stability of the equipment in the event of failure must be ensured.

Thus, the Applicant has devised a medical multi-laser amplification output device capable of adjusting the configuration of the optical system favorable to the laser focusing of the servo mirror, precise offset adjustment, stable sequence control, and appropriate temperature control of the light resonance part.

U.S. Patent No. 9939631

An aspect of the present invention is to provide a medical multi-laser amplification output device having an optical system configuration that minimizes a divergence angle of a laser resonated in a laser cavity and is advantageous for incidence on optical fibers.

Also, the present invention provides a medical multi-laser amplification output device capable of controlling an offset so as to eliminate an error that may be sensitive to an output pulse, such as an overshoot depending on equipment and an environment such as a temperature.

The present invention also provides a medical multi-laser amplification output device capable of ensuring continuity of output even if an error occurs in any light resonance system in a multi-channel laser cavity.

The present invention also provides a medical multi-laser amplification output device capable of maintaining a light resonance part at a low temperature by providing a cooling system having a high cooling efficiency with a minimum volume.

According to an aspect of the present invention, there is provided a medical multi-laser amplification output apparatus comprising: a plurality of laser cavities; and an optical system for guiding light sequentially output from the plurality of laser cavities in a single path to form a single output laser A light resonance unit configured; A processor unit for determining energy to excite a medium of the laser cavity and controlling the optical resonator unit; And a cooling unit for controlling the temperature of the optical resonator unit. In the process of controlling the initial pulse of the laser cavity, the processor unit applies an offset signal having a gradually increasing pulse width to reach a set output value of the laser cavity And adjusting the offset of the light resonance part by fixing the pulse width of the offset signal.

Preferably, when the offset signal is applied, the processor unit may gradually increase the pulse width of the offset signal while the voltage of the offset signal is fixed.

Preferably, the optical system includes: a pair of reflector mirrors provided in front of and behind the laser rod; And a relay mirror for focusing the light output through the pair of reflector mirrors, and a servo mirror for guiding the light reflected from each of the relay mirrors provided in each of the laser cavities to an output line, Wherein the servo mirror rotates under the control of the processor unit to focus the light sequentially output by each of the laser cavities to a single path of the output line, the reflector mirror comprising a rear reflector mirror positioned on the rear surface of the laser rod The front reflector mirror having a negative curvature surface and positioned in front of the laser rod may have a flat surface.

Preferably, when an error occurs in any one of the laser cavities, the processor unit excludes the output order of the errored laser cavity on the sequence, and instructs the next laser cavity to skip the order, The light resonance unit can be controlled to ensure continuity.

Preferably, the cooling unit includes: a cooling pump connected to the light resonance unit and supplying cooling water; And a radiator having a line through which a supply line connected to the optical resonance part of the cooling pump is branched and part of the cooling water supplied to the optical resonance part flows.

According to another aspect of the present invention, there is provided a medical multi-laser amplification output apparatus, comprising: a light resonance unit comprising a plurality of laser cavities; and an optical system for guiding light sequentially output from the plurality of laser cavities in a single path to form a single output laser; A processor unit for determining energy to excite a medium of the laser cavity and controlling the optical resonator unit; And a cooling unit for controlling the temperature of the light resonance unit, wherein the processor unit excludes an output order of an errory laser cavity on a sequence when an error occurs in any one of the laser cavities, And the optical resonance unit is controlled so as to ensure continuity of output by commanding the cavity to skip the order.

The present invention solves the problem that theoretically calculated offset value is not accurately reflected in the actual output value due to the problem of the stabilization period and the overshoot of the laser. Further, the present invention has an optical system structure that minimizes the divergence angle of a resonated laser and is advantageous for incident on an output line. In addition, the present invention can provide a cooling system in which a supply line connected to the light resonance unit is branched so that cooling water flows in parallel, thereby achieving high cooling efficiency with a small volume. Further, the present invention controls the output order of the laser cavity in which the error occurs, from the sequence and controls to skip the order to the next laser cavity to ensure the continuity of the output. Thus, the present invention can provide a medical multi-laser amplification output device capable of precise laser output and stable control.

1 shows a medical multi-laser amplification output apparatus according to an embodiment of the present invention.
2 shows an optical resonator according to an embodiment of the present invention.
3 shows an optical system according to an embodiment of the present invention.
Fig. 4 shows a control operation of the servo mirror 107 according to the embodiment of the present invention and the optical path accordingly.
5 shows a cooling section according to an embodiment of the present invention.
6 shows a cooling water circulation path of the cooling section according to the embodiment of the present invention.
7 shows a control screen of the processor unit according to the embodiment of the present invention.
8 shows an offset control principle of a processor unit according to an embodiment of the present invention. 8A shows a conventional offset signal and an output waveform accordingly. 8B shows an offset signal of the processor unit and an output waveform according to an embodiment of the present invention.
9 shows a sequence control principle of the processor unit according to the embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to or limited by the exemplary embodiments. Like reference numerals in the drawings denote members performing substantially the same function.

The objects and effects of the present invention can be understood or clarified naturally by the following description, and the purpose and effect of the present invention are not limited by the following description. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Fig. 1 shows a medical multi-laser amplification output apparatus 1 according to an embodiment of the present invention. Referring to FIG. 1, the multi-laser amplification output device 1 may include an optical resonator 10, a processor 30, a cooling unit 50, and a display unit 70. 1, the cooling section 50 is located on the opposite side of the main body in which the processor section 30 is located. Therefore, the shape of the cooling unit 50 will be described later with reference to FIG. 5 and FIG.

The medical multi-laser amplification and output apparatus 1 according to the present embodiment is a device that has a plurality of sequentially pumped laser rods, combines the outputs of the respective laser rods with one pulse laser, and outputs the result.

When pumping a single laser rod at a high repetition rate, the system requires high cooling efficiency. On the other hand, when a plurality of laser bars are used, the repetition rate of pumping and outputting each cavity can be reduced, and the thermal accumulation is reduced as compared with the single cavity system, so that the temperature control can be performed by the air cooling / water cooling system. In this embodiment, a multi-channel light resonance portion 10 is realized which realizes a plurality of laser cavities 101 for optical resonance.

The output laser of the light resonance part 10 is the sum of the laser load output in the laser cavity 101, and the output pulse speed and average energy level are high. In this embodiment, the laser cavity 101 is composed of four, and a Ho: YAG laser rod can be used. Each laser cavity 101 is pulsed at 10 Hz, and the four cavity 101 outputs are combined and interleaved with a single output laser. The interleaved output laser has a pulse frequency of 40 Hz.

2 shows a light resonance part 10 according to an embodiment of the present invention. 2, the optical resonator unit 10 includes a plurality of laser cavities 101 and an optical system 103 for forming a single output laser by guiding light sequentially output from the plurality of laser cavities 101 through a single path , 105, 107, 109).

The plurality of laser cavities 101 are fixed at four quadrants. The first laser cavity 101 (a) and the second laser cavity 101 (b) are a pair of laser cavities arranged on the same x-axis. The third laser cavity 101 (c) and the fourth laser cavity 101 (d) are also a pair of laser cavities arranged on the same x-axis. The first laser cavity 101 (a), the third laser cavity 101 (c), the second laser cavity 101 (b) and the fourth laser cavity 101 (d) . The laser cavity 101 may be provided with a gain medium for laser excitation and an optical pump.

The first to fourth laser cavities 101 (a), 101 (b), 101 (c), and 101 (d) are sequentially pumped to oscillate the laser. In this embodiment, the first to fourth laser cavities 101 (a), 101 (b), 101 (c), and 101 (d) are pulsed at 10 Hz, respectively. The laser beams sequentially output from the first to fourth laser cavities 101 (a), 101 (b), 101 (c) and 101 (d) at a pulse frequency of 10 Hz are passed through the optical systems 103, 105, 107, , And the pulse frequency of the output laser is amplified to be 40 Hz.

3 shows optical systems 103, 105, 107, and 109 according to an embodiment of the present invention. 3, the optical systems 103, 105, 107, and 109 may include a plurality of reflector mirrors 103, a plurality of relay mirrors 105, and a servo mirror 107. FIG. 3 also shows the optical path of the laser output from one of the laser cavities 101.

The reflector mirror 103 can resonate and amplify the output laser of the laser cavity 101 with the reflectors disposed in front of and behind the laser cavity 101. The reflector mirror 103 includes a rear reflector mirror 103 (b) positioned on the rear surface of the laser cavity 101 and a front reflector mirror 103 (a) positioned on the front surface of the laser cavity 101.

The front reflector mirror 103 (a) and the rear reflector mirror 103 (b) constitute a resonator so as to oscillate the laser. The optical system is configured to determine the resonance system. The front reflector mirror 103 (a) is partly reflective coated to resonate part of the output laser of the laser cavity 101 and output a part thereof. On the other hand, the rear reflector mirror 103 (b) is entirely reflective coated. One pair of the front reflector mirror 103 (a) and the rear reflector mirror 103 (b) is provided for each laser cavity 101. In this embodiment, since the optical resonator 10 is constituted by the first to fourth laser cavities 101 (a), 101 (b), 101 (c) and 101 (d), the reflector mirror 103 A total of eight are arranged in the four laser cavities 101 (a), 101 (b), 101 (c), and 101 (d).

In the present embodiment, the rear reflector mirror 103 (b) has a negative curvature surface, and the front reflector mirror 103 (a) is configured to have a flat surface. The curvatures of the front reflector mirror 103 (a) and the rear reflector mirror 103 (b) are closely related to the output of the laser being resonated. 1 of the above-mentioned U.S. Patent No. 9939631 discloses a structure corresponding to the rear reflector mirror 103 (b) of this embodiment as a high reflector mirror and corresponds to the front reflector mirror 103 (a) The output coupler (partial reflector) was started. In Figure 1 of U.S. Patent No. 9939631, a high reflector mirror has a flat surface and an output coupler (partial reflector) has a concave surface. 3 in contrast to the embodiment of the present invention.

The optical system according to the present embodiment can minimize the divergence angle of the laser that is formed by the concave surface of the rear reflector mirror 103 (b) of the total reflection and resonates. Accordingly, it is designed to be advantageous to the incidence of the output line optical fiber. Further, the front reflector mirror 103 (a) has a flat mirror surface. If the surface of the front reflector mirror 103 (a) is concave, the divergence angle becomes large when the laser is oscillated, which may cause technical difficulties in adjusting the incidence of the optical fiber.

The plurality of relay mirrors 105 collectively refers to a configuration of an optical system that transmits the laser beam emitted from the reflector mirror 103 to the servo mirror 107 and transmits the light incident on the servo mirror 107 to the output line. 3, a plurality of relay mirrors 105 are arranged in the order of a first relay mirror 105 (a) which directly receives an oscillation laser of the front reflector mirror 103 (a) and reflects it at a predetermined angle, ). The first relay mirror 105 (a) is arranged coaxially with the front reflector mirror 103 (a). In this embodiment, the first relay mirror 105 (a) may be configured with a concave surface so as to minimize divergence of the laser.

The plurality of relay mirrors 105 includes a second relay mirror 105 (b) for causing the laser reflected from the first relay mirror 105 (a) to enter the servo mirror 107. The plurality of relay mirrors 105 includes a third relay mirror 105 (c) for making the laser beam reflected by the servo mirror 107 incident on the output line. A pair of the first relay mirror 105 (a) and the second relay mirror 105 (b) are arranged in the laser cavity 101, respectively. The third relay mirror 107 detects the path of the laser beams sequentially output from the first to fourth laser cavities 101 (a), 101 (b), 101 (c), and 101 ), So that only one optical system may be disposed.

The servo mirror 107 can be rotated under the control of the processor unit 30 to focus the light sequentially output by the respective laser cavities 101 to a single path of the output line. The servo mirror 107 is a reflecting mirror rotated by 360 degrees, and a servo motor for rotating the servo mirror 107 and an encoder for controlling the turning angle of the mirror 107 can be modularized together. The servo mirror 107 is rotated to reflect the sequential laser output of the four laser cavities 101 (a), 101 (b), 101 (c) and 101 (d) in a single path. Therefore, the rotation angle of the servo mirror 107 is adjusted in the range of 90 degrees for each of the laser cavities 101 (a), 101 (b), 101 (c), and 101 (d).

After the sequential laser output is integrated into the single path through the servo mirror 107, an optical path is formed in the output line of the optical resonator unit 10 in which the optical fiber is provided through the third relay mirror 105 (c) . In FIG. 3, the optical system of the output line is collectively referred to as reference numeral 109. A plurality of reflection mirrors may be additionally provided in the optical system 109 of the output line according to the arrangement and design characteristics of the optical fibers.

Fig. 4 shows a control operation of the servo mirror 107 according to the embodiment of the present invention and the optical path accordingly. Fig. 4A is a graph showing the relationship between the output of the first laser cavity 101 (a) among the four laser cavities 101 (a), 101 (b), 101 (c) Optical path. Fig. 4B is a view showing a state in which the second laser cavity 101 (b) out of the four laser cavities 101 (a), 101 (b), 101 (c) Optical path.

The optical path of the optical resonator unit 10 according to the present embodiment is summarized as follows. The laser beam of the laser cavity 101 is excited and the outputted laser resonates and oscillates through the front reflector mirror 103 (a) and the rear reflector mirror 103 (b). The pumped laser includes a front reflector mirror 103 (a), a first relay mirror 105 (a), a second relay mirror 105 (b), a servo mirror 107, and a third relay mirror 105 ) To the optical system 109 of the output line. In this case, the optical resonance portion 10 is formed with a considerable distance from the optical path of the laser up to the optical fiber of the output line. Due to the characteristics of the laser, it is required to minimize the divergence of the laser because the size of the laser increases when the long distance is relayed. The key is to minimize the divergence of the laser and focus the output laser at the center point of the servo mirror 107. In this process, the optical resonator 10 according to the present embodiment includes the front reflector mirror 103 (a) as a flat surface and the first relay mirror 105 (a) as a concave surface.

5 shows a cooling section 50 according to an embodiment of the present invention. The multi-laser amplification output device 1 according to the present embodiment has been described above as requiring a relatively low temperature maintenance as a holmium YAG laser. The cooling system of the multi-laser amplification output device 1 can be one of the main technical challenges to improve the overall laser output. Therefore, the cooling unit 50 system is provided in a configuration for cooling the heat generated in the light resonance unit 10 generated in the pumping process. The cooling section 50 includes a temperature sensor to control the temperature of the light resonance section 10.

The cooling section 50 includes a cooling pump 51, a cavity cooling line 52, a filter 53, a branch line 54, a radiator 55, a cooling tank 57, a supply line 58, 59).

The cooling pump 51 is connected to the light resonance part 10 to supply cooling water. The cooling pump 51 is connected to the cooling tank 57 through a supply line 58. Cooling water is introduced into the cooling pump 51 from the cooling tank 57 and the cooling pump 51 introduces the cooling water into the light resonance unit 10 through the cavity cooling line 52 to make the light resonance unit 10 constant Temperature control. The cavity cooling line 52 may include one or more filters 53. In this embodiment, the filter 53 may include a micro filter 53 (a) and a DI filter 53 (b).

The radiator 55 is made up of vertical column corrugations. The radiator 55 forms a circulation path of the cooling water therein, and radiates the heat energy of the cooling water to the outside during the circulation of the cooling water. A fan 59 is disposed on the rear surface of the radiator 55 to increase the cooling efficiency of the radiator 55.

The radiator 55 has a line in which a supply line connected to the light resonance part 10 of the cooling pump 51 is diverged and a part of the cooling water supplied to the light resonance part 10 flows. The configuration in which a part of the cooling water supplied to the light resonance part 10 is branched into a line flowing into the radiator 55 is referred to as a branch line 54. [

A branch line 54 is formed in the cavity cooling line 52. The branch line 54 is connected to a radiator 55. The cooling water flows into the radiator 55 through the branch line 54 to emit heat energy. Note that in this embodiment, the inflow path of the radiator 55 is the branch line 54 branched from the cavity cooling line 52. [ Generally, a line of cooling water circulated through the light resonance part 10 flows into the radiator 55. However, in the present embodiment, the line of the cooling water circulated through the light resonance portion 10 is connected to the cooling tank 57. That is, the cavity cooling line 52 is connected to the cooling tank 57 via the light resonance portion 10.

The multi-laser amplification output device 1 is required to be controlled in a constant range by minimizing the temperature shift. In the present embodiment, the cooling water whose temperature has been raised via the light resonance portion 10 is collected in the cooling tank 57 through the cavity cooling line 52. As the cooling water with a high temperature is accommodated on the cooling tank 57 in a large amount, the displacement of the temperature becomes low and the temperature value of the cooling water becomes constant. Note that the cooling water whose temperature has been lowered through the radiator 55 also flows into the cooling tank 57. That is, in the cooling unit 50 system as in the present embodiment, the radiator 55 not only lowers the temperature of the cooling water, but also lowers the temperature of the cooling water in the cooling tank 57 and also uniformizes the temperature value.

6 shows the cooling water circulation path of the cooling unit 50 according to the embodiment of the present invention. Referring to FIG. 6, the cooling unit 50 according to the embodiment of the present invention is divided into a cooling water path of C1 and a cooling water path of C2.

The cooling water flows into the optical resonator unit 10 from the cooling tank 57 through the cooling pump 51 and the cavity cooling line 52 in order. C2 flows into the radiator 55 through the branch line 54 in which the cavity cooling line 52 to which the cooling water is supplied from the cooling pump 51 to the light resonance portion 10 is branched. The cooling water circulated through the radiator 55 flows into the cooling tank 57 again. The path of C1 is a path for cooling the laser of the light resonance portion 10, and the path of C2 is a path for cooling the cooling water. The cooling system 50 according to the present embodiment has a common path from the cooling tank 57 to the cooling pump 51. Therefore, the laser is cooled on the cooling tank 57 to be combined with the cooling water whose temperature is increased and the cooling water which is cooled, and the temperature is uniformly leveled, thereby enabling more stable temperature control.

7 shows a control screen of the processor unit 30 according to an embodiment of the present invention. The control screen of the processor unit 30 according to FIG. 7 can be displayed through the display unit 70. FIG. The display unit 70 is provided as a control panel, and can change an operation condition of the processor unit 30 or display an operation state of the equipment.

7, the display unit 70 is provided with a status window READY, a guide beam UI (PILOT), an information button i, a system power button, a frequency control UI (FREQUENCY), an energy control UI (ENERGY) The status window (POWER), the instrument's offset parameter load UI (DEFAULT), the main alarm UI (FIBER, SAFETY GLASS, LAMP TEMP), temperature display window (TEMP) and other alarm and instrument information windows may be provided.

The status window (READY) provides the ability to switch between standby and ready modes to provide safe laser output operation. In the ready mode, the laser is oscillated when the user presses a separate foot switch. The guide beam UI (PILOT) can adjust the guide beam brightness of the laser output path. Touch or drag to lighten or weaken the brightness of the guide beam. The information button (i) provides information such as the S / N ratio of the system, the amount of lamp usage, the time, and the date of manufacture. The system power button can display the button operation sequence or image together to safely shut down the equipment.

The frequency control UI (FREQUENCY) allows you to set the number of times the laser fires per second. The user can operate the (+) and (-) buttons to set the pulse frequency of the output laser. The laser cavities 101 (a), 101 (b), 101 (c) and 101 (d) each output 10 Hz of laser do. The energy control UI (ENERGY) allows you to set the energy of the output laser. The power status window (POWER) displays the frequency x energy set by the frequency control UI (FREQUENCY) and the energy control UI (ENERGY). The main alarm UI (FIBER, SAFETY GLASS, LAMP, TEMP) displays the status of the main alarm that the user should know. The temperature display (TEMP) shows the current temperature of the equipment.

Loading the offset parameter of the instrument The UI (DEFAULT) loads the set parameters of the offset set instrument. The offset parameter can be set by selecting an administrator mode on the display unit 70. [

The processor unit 30 determines the energy for exciting the medium of the laser cavity 101 and controls the light resonance unit 10. [ In the process of controlling the initial pulse of the laser cavity 101, the processor unit 30 applies an offset signal having a gradually increasing pulse width to fix the pulse width of the offset signal when reaching the set output value of the laser cavity 101 The offset of the light resonance portion 10 can be adjusted. The processor unit 30 can gradually increase the pulse width of the offset signal in a state where the voltage of the offset signal is fixed when the offset signal is applied.

8 shows an offset control principle of a processor unit according to an embodiment of the present invention. 8A shows a conventional offset signal and an output waveform accordingly. 8B shows an offset signal of the processor unit and an output waveform according to an embodiment of the present invention.

Referring to FIG. 8A, the conventional offset control is set so that a predetermined output value of the laser is outputted by applying an offset signal having a constant pulse width (for example, 600 占 퐏). In theory, it is assumed that the pulse width of the offset signal for outputting 1J of the laser is 600 μs. Here, when the offset signal is applied, there is an overshooting value exceeding 1J due to laser pumping process, and the output value converges to 1J through the stabilization period. However, the laser is an extremely sensitive device, and it can not accurately derive the theoretical value of the offset setting by the hardware characteristics, the temperature of the installed place, and the like. In the example of FIG. 8A, the laser output may exceed 1J or less than 1J depending on the case.

Thus, the processor unit 30 according to the present embodiment applies an offset signal having a variable pulse width as shown in FIG. 8B. Here, the voltage value of the offset signal is fixed. The pulse width of the initial signal applied to the offset signal applied by the processor unit 30 is the shortest, and the pulse width increases with time. The processor unit 30 checks the energy of the output laser and determines the offset signal having a pulse width at that time when the set value (for example, 1J) is reached.

As a result of performing the offset control process in the above-described manner, the processor unit 30 stabilizes the initial energy and prevents the system from being damaged due to an excessive overshoot in the output stabilization period. During the offset process, the user can set the initial pulse width of the offset signal and the pulse width increase amount at the start.

9 shows a sequence control principle of the processor unit 30 according to the embodiment of the present invention. 9 shows the operation signals of the four laser cavities 101 (a), 101 (b), 101 (c) and 101 (d) controlled by the processor unit 30 in a time (x axis) line. The processor unit 30 sequentially receives the operation signals of the first laser cavity 101 (a), the second laser cavity 101 (b), the third laser cavity 101 (c), and the fourth laser cavity 101 101 (d)).

 At this time, the processor unit 30 determines that any one of the laser cavities 101 (a), 101 (b), 101 (c), and 101 (d) The light resonance portion 10 is arranged to exclude the output order of the laser cavity 101 (b) in which the error has occurred on the sequence and to instruct the next laser cavity 101 (c) to skip the order, Can be controlled.

9, when the life of the flash lamp of the second laser cavity 101 (b) has expired or an error has occurred in the optical system disposed in the second laser cavity 101 (b), the laser reaches the output line Otherwise, a different laser output value will appear. At this time, the processor unit 30 detects an error in the second laser cavity 101 (b). When the above error signal is detected, the processor unit 30 omits the operation signal of the second laser cavity 101 (b). The processor unit 30 also outputs the output sequence to the first laser cavity 101 (a) - the second laser cavity 101 (b) - the third laser cavity 101 (c) - the fourth laser cavity 101 (d)) into the first laser cavity 101 (a) - the third laser cavity 101 (c) - the fourth laser cavity 101 (d), stores the sequence at this time, The above procedure is continuously performed.

By changing the sequence of the processor unit 30, although the output laser may have a smaller power than that of the conventional laser, and the procedure time may be prolonged, at least the continuity of the output is maintained, .

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. will be. Therefore, the scope of the present invention should not be limited to the above-described embodiments, but should be determined by all changes or modifications derived from the scope of the appended claims and equivalents of the claims.

1: Multi-laser amplification output device
10: light resonance part
101: laser cavity
103: Reflector mirror
105: Relay mirror
107: Servo mirror
109: Output line optical system
30:
50:
51: Cooling pump
52: Cavity cooling line
53: Filter
54: branch line
55: Radiator
57: Cooling tank
59: Fan
70:

Claims (6)

A medical multi-laser amplification output apparatus comprising:
An optical resonator comprising a plurality of laser cavities and an optical system for guiding the laser sequentially output by the plurality of laser cavities in a single path to form a single output laser;
A processor unit for determining energy to excite a medium of the laser cavity and controlling the optical resonator unit; And
And a cooling section for controlling the temperature of the light resonance section,
The processor unit,
Adjusting an offset of the light resonance part by fixing the pulse width of the offset signal when a predetermined output value of the laser cavity is applied by applying an offset signal whose pulse width gradually increases in the course of controlling the initial pulse of the laser cavity,
The optical system includes:
In each of the laser cavities,
A pair of reflector mirrors provided in front of and behind the laser cavity; And
And a relay mirror for focusing the light output through the pair of reflector mirrors,
Further comprising a servo mirror for guiding the light reflected from each of the relay mirrors provided in each of the laser cavities to an output line,
The servo mirror includes:
The laser cavity is rotated under the control of the processor unit to focus the light sequentially output by each of the laser cavities to a single path of the output line,
The reflector mirror
Wherein the rear reflector mirror positioned on the rear surface of the laser cavity has a negative curvature surface and the front reflector mirror positioned on the front surface of the laser cavity has a flat surface.
The method according to claim 1,
The processor unit,
Wherein the pulse width of the offset signal is gradually increased while the voltage of the offset signal is fixed when the offset signal is applied.
delete The method according to claim 1,
The processor unit,
When an error occurs in any one of the laser cavities,
Wherein the optical resonance unit controls the optical resonance unit to exclude an output order of an errory laser cavity on a sequence and instruct the next laser cavity to skip the order so as to ensure continuity of output.
The method according to claim 1,
The cooling unit includes:
A cooling pump connected to the light resonance unit and supplying cooling water; And
And a radiator having a line through which a supply line connected to the optical resonance part of the cooling pump is branched and a part of the cooling water supplied to the optical resonance part flows.
delete

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