KR101736693B1 - Method and apparatus for processing brittle material with filamentation of laser diffraction beam - Google Patents

Abstract

The present invention discloses a laser machining apparatus for machining a brittle material using a laser diffraction beam filament. The laser processing apparatus according to the present invention is characterized in that: A laser generator for generating a microwave pulse laser beam; A diffraction optical system for diffracting the laser beam to generate a ring-shaped laser diffraction beam in an orthogonal cross section; And a focusing optical system for focusing the laser diffraction beam to form a focus beam before reaching the brittle material, wherein the focus beam is formed only between the focusing optical system and the brittle material, the focus beam defocusing, And enters the inside of the brittle material, thereby processing the brittle material by filamentation.
According to the present invention, the brittle material can be processed by using the filament of the laser diffraction beam to process the brittle material so that the processed surface is smooth and cracks are not generated.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brittle material processing method using a laser diffraction beam filament,

The present invention relates to a laser processing method and apparatus for brittle material processing using filamentation of a laser diffraction beam, and more particularly, to a laser processing method and apparatus for laser processing a brittle material using a laser diffraction beam And focuses the focused beam before defocusing the defocused beam to form a focused beam. The defocused beam is then incident on the brittle material, thereby processing the brittle material using a filamentation phenomenon.

Direct laser processing of the inside of the transparent material is useful not only for reducing the process time but also for eliminating the anxiety factors such as micro cracking due to the surface damage of the material occurring in the existing process and inconsistency of the line after laser processing . However, since it is processed inside the material, the equipment to be used for processing is confined to a special laser. In case of using a general laser, due to heat effect, characteristic change of material and microcrack may occur. And the occurrence of micro cracks due to the damage of the surface of the material.

In order to solve such problems, it is effective to use a femtosecond laser having a wavelength of visible light and near infrared rays and having a short pulse width, which is transmitted through the glass, in order to perform micromachining in the glass.

When the femtosecond laser is focused inside the glass, a phenomenon occurs in which the plasma is generated at a certain length under a certain range of several to several tens of Rayleigh lengths. This phenomenon is called filamentation. In a material having a Kerr effect such as a transparent glass, a focused laser pulse must be irradiated with a pulse exceeding a threshold value in order to cause self-focusing. Plasma dispersion occurs after magnetic focusing, and the more focused beam due to magnetic focusing is large enough to exceed the local damage threshold, but the pulse width is not long enough to cause avalanche ionization, resulting in ionization and permanent It does not damage. When the self-focusing and the plasma dispersion are continuously generated in a balanced manner, a continuous refractive index change occurs over a Rayleigh length, and this phenomenon is referred to as filamentation.

Fig. 1 shows a schematic diagram of a laser machining apparatus for machining a transparent brittle material according to the prior art.

A typical laser processing apparatus includes a laser generating unit and an optical system for beam transmission, a beam attenuator, a shutter, a three-axis stage, and a focusing lens, and may further include a CCD camera.

The laser beam emitted from the laser generation part reaches the focusing lens via the transmission optical system and the output adjusting beam attenuator, and is incident on the brittle material to be processed. The three-axis stage sets the coordinates to be irradiated on the brittle material specimen, and operates the shutter so that the laser can be irradiated according to the user's intention. The machining focus can be set and the machining conditions can be observed in real time through the CCD camera.

By applying a femtosecond laser to such a laser processing apparatus, the brittle material can be processed by filamentation in a brittle material such as glass.

Particularly, in the display field, since it is necessary to precisely cut the glass to be contained in the cover, there is a difficulty in mass production and quality maintenance in cutting a glass having a thickness of several tens to several hundreds of micrometers. Using filamentation, it is possible to make refractive index modification, cracking, and cavity generation in tens to several hundreds of micrometers scale by laser irradiation at one point, and various methods are applied to the processing of brittle materials such as glass have.

In the case of a pulse laser oscillated in the form of a pulse, the energy possessed by a pulse is called pulse energy. The pulse energy alone has little significance in laser processing. The pulse energy, repetition rate, and spot size, The amount of energy to be consumed is determined.

In the case of a pulsed laser which is generally applied, when a peak power is used, a phenomenon of magnetic focusing effect in the brittle material is insufficient. 2, the output of the pulse is abruptly decreased until the output of the pulse of the next period after the output of the first pulse as shown in FIG. 2 (a), and the pulse output is reduced A burst mode in which a pulsed laser is implemented only by a peak output as shown in FIG. 2 (b) has been proposed by time-shifting and rearranging pulses repeatedly generated to solve the problem.

However, when the brittle material is processed in the burst mode using the filament inside the transparent brittle material, the processed surface of the brittle material does not smooth smoothly due to the repetitive injection of the pulsed laser and causes a fine crack . The presence of such fine cracks on the work surface leads to cracks from cracks when an external impact is applied to the processed brittle material, and the strength of the processed brittle material is lowered.

Korean Patent Publication No. 10-2000-0035145

SUMMARY OF THE INVENTION The present invention has been made to overcome the problems of the prior art as described above. In the conventional method using a femtosecond laser, repeated pulse lasers are injected to cause filamentation in a transparent brittle material, The surface to be processed is not smooth due to the pulse interval and a fine crack is generated.

Furthermore, when there is a minute crack on the machined surface of the processed brittle material, cracks are induced from a crack when an external impact is applied, and the strength of the processed brittle material is lowered.

According to an aspect of the present invention, there is provided a laser processing apparatus comprising: a laser generating unit for generating a microwave laser beam; A diffraction optical system for diffracting the laser beam to generate a ring-shaped laser diffraction beam in an orthogonal cross section; And a focusing optical system for focusing the laser diffraction beam to form a focus beam before reaching the brittle material, wherein the focus beam is formed only between the focusing optical system and the brittle material, the focus beam defocusing, And the brittle material is processed by filamentation into the inside of the brittle material, thereby processing the brittle material.

The laser processing apparatus according to one aspect of the present invention may further comprise means for adjusting a width of a laser beam incident on the diffractive optical system to adjust a length of the focal beam.

Further, in the laser processing apparatus according to an aspect of the present invention, the focusing optical system may include a collimation lens for converging or diffusing the laser diffraction beam, and a condensing lens for converging the laser diffraction beam passing through the collimation lens, Means for adjusting a distance between the diffraction optical system and the collimation lens to adjust a length of the focal beam; means for adjusting a distance between the collimation lens and the focusing lens; And means for adjusting the width of the laser beam incident on the diffractive optical system.

According to another aspect of the present invention, there is provided a laser processing method comprising the steps of: generating a laser beam; A diffraction beam generating step of diffracting the laser beam to generate a ring-shaped laser diffraction beam on an orthogonal cross section; A focus beam forming step of focusing the laser diffraction beam through a focusing optical system and forming a focus beam only between the focusing optical system and the brittle material; And a machining step of defocusing the focal beam and entering the inside of the brittle material to process the brittle material by filamentation.

In the laser beam generating step of the processing method according to the present invention, a microwave laser beam having a pulse width of femtosecond (FS) to picosecond (PS) can be generated.

According to the present invention, the brittle material can be processed by using the filament of the laser diffraction beam to process the brittle material so that the processed surface is smooth and cracks are not generated.

In particular, in the case of a Gaussian laser beam, as the distance from the focused point of the laser beam is increased, the line width is diffused and the peak shape is completely deformed. However, in the present invention, even if the laser beam is distanced from the point where the laser beam is focused using the laser diffraction beam Since the peak shape is maintained, the shape and power of the beam are maintained during defocusing using filaments inside the brittle material, so that the brittle material can be processed more effectively.

Further, the beam length of the laser diffraction beam can be easily adjusted to perform processing suitable for various brittle materials.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a laser processing apparatus for processing a transparent brittle material according to the prior art; FIG.
2 shows a conventional pulse laser output and a burst mode pulse laser output according to the prior art.
3 is a schematic diagram of a first embodiment of a laser machining apparatus for machining a brittle material according to the present invention.
4 is a laser diffraction beam generated from a first optical system in a laser processing apparatus for brittle material processing according to the present invention;
5 is a conceptual diagram for adjusting the length of an incident beam incident on a transparent brittle material from a third optical system in a laser processing apparatus for brittle material processing according to the present invention.
6 is a graph of the power density of a Gaussian laser beam and a laser diffraction beam according to the present invention.
7 is a schematic diagram of a second embodiment of a laser machining apparatus for machining a brittle material according to the present invention.
8 illustrates an embodiment in which the focal length of the laser diffraction beam is adjusted according to the second embodiment.
9 is a schematic diagram of a third embodiment of a laser machining apparatus for machining a brittle material according to the present invention.
10 illustrates an embodiment in which the focal length of the laser diffraction beam is adjusted according to the second embodiment.
11 is a view illustrating an embodiment in which the focal length of the laser diffraction beam is adjusted by adjusting the beam width of the laser beam while applying the second embodiment.
12 is a flowchart of a brittle material processing method using a filament of a laser diffraction beam according to the present invention.
13 is a photograph showing a glass processing result according to the prior art and a glass processing result according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.

First, the terminology used in the present application is used only to describe a specific embodiment, and is not intended to limit the present invention, and the singular expressions may include plural expressions unless the context clearly indicates otherwise. Also, in this application, the terms "comprise", "having", and the like are intended to specify that there are stated features, integers, steps, operations, elements, parts or combinations thereof, But do not preclude the presence or addition of features, numbers, steps, operations, components, parts, or combinations thereof.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

The present invention discloses a method of processing a brittle material by using a laser diffraction beam after diffracting a microwave laser beam having a Gaussian power density and a laser processing apparatus for implementing the method.

First, a laser processing apparatus according to the present invention will be described, and a method for processing a brittle material using a laser processing apparatus according to the present invention will be described.

Fig. 3 shows a schematic diagram of a first embodiment of a laser machining apparatus for machining a brittle material according to the present invention.

The laser processing apparatus according to the present invention may include a laser generating unit 100, a first optical system 200, a second optical system 300, and a third optical system 400.

The laser generating unit 100 generates a microwave laser beam, and may generate a microwave laser beam having a pulse width of femtosecond (FS) to picosecond (PS).

The first optical system 200 diffracts the laser beam propagated from the laser generation unit 100 to form a ring-shaped laser diffraction beam in an orthogonal sectional shape. As an example, an axicon lens can be applied.

As an example of generating a laser diffraction beam through the first optical system 200, FIG. 4 shows a power density distribution for a laser diffraction beam in a Gaussian laser beam and the present invention, wherein the Gaussian laser beam shown in FIG. 4 (a) In the case of a laser beam, as the propagation distance increases, the beam spreads and spreads. As the power of the beam is dispersed, the power density sharply drops.

In contrast, according to the power density distribution of the laser diffraction beam according to the present invention shown in FIG. 4 (b), the microwave laser beam generated from the laser generator 100 has a Gaussian power density. The laser beam is diffracted through the first optical system 200 to be generated as a laser diffraction beam. A wave-like power density spreading from the central portion is formed on the focal point of the laser diffraction beam, and a ring- A laser diffraction beam having a power density of < RTI ID = 0.0 > Although the laser diffraction beam is shown in FIG. 4 as having a power density in the form of a ring, it may be modified into a laser diffraction beam having a power density of a modified form by adjusting the first optical system 200.

In the present invention, a laser beam in the form of a Gaussian beam generated by the laser generator 100 is generated as a laser diffraction beam through the first optical system 200, and a brittle material is processed with a laser diffraction beam to maintain a more stable power density This will be described in detail in the following embodiments.

3, the second optical system 300 converges or diffuses the laser diffraction beam from the first optical system 200 to adjust the length of the laser diffraction beam For this purpose, a collimation lens may be included.

The third optical system 400 forms a focal point on the upper air layer of the brittle material 10 to be processed while converging the laser diffraction beam whose length has been adjusted through the second optical system 300 to enter the brittle material 10, And may include a kind of focusing lens.

Further, in the present invention, the distance between the first optical system 200 and the second optical system 300, or the distance between the second optical system 300 and the third optical system 400, When the laser diffraction beam generated by the first optical system 200 passes through the second optical system 300 and is incident on the third optical system 400, the beam length of the brittle A difference occurs in the beam length of the beam incident on the work 10. 5, the incident beam focused through the third optical system 400, which is a kind of focusing lens, is focused on the incident beam as shown in FIG. 5 to the width (2W _O) of claim 3, the focusing beam when a is d _O width of the input beam, referred to the frequency of the beam f and wavelength λ is incident to the optical system 400 as shown in [equation 1] . Here, M ² is an indicator of how close the laser beam is to a single Gaussian mode. If this value is lower, the closer to the single mode, the more complete it is .

[식 1]

[Formula 1]

Since the width 2W _O of the converging beam is inversely proportional to the width D _O of the beam based on the above-mentioned [Expression 1], the beam length is determined according to the width D _O of the beam. At this time, the width D _o of the beam is determined according to the convergence and diffusion by the second optical system 300.

The convergence efficiency of the beam can be improved through the convergence or diffusion of the beam according to the adjustment of the separation distance between the optical systems 200, 300, and 400 based on the beam characteristics. The beam efficiency of the beam incident into the brittle material The Kerr effect can be improved and the self focusing effect can be enhanced.

According to the present invention, the brittle material 10 is processed by using the laser diffraction beam in the brittle material 10 and the brittle material 10 is processed by the laser beam of the brittle material 10 rather than the laser beam of the Gaussian beam type used in the prior art. 6, and a power density graph of the laser diffraction beam according to the present invention will be described with reference to FIG.

6A, 6B, 6C, 6D and 6E show the power density of the laser beam at the propagation distance of 0 mm, while the propagation distance of the laser beam is 500 mm The power density is shown as it goes away.

As shown in FIG. 6 (a), when the propagation distance of the laser beam is 0 mm, there is hardly a difference in power density between the Gaussian laser beam and the laser diffraction beam. However, as shown in FIGS. 6B and 6C, As the propagation distance of the beam gradually increases, the peak power of the Gaussian laser beam decreases sharply. However, the laser diffraction beam keeps the shape of the peak power continuously. As shown in FIGS. 6D and 6E, If the propagation distance of the laser beam is more than 1,500 mm, the Gaussian laser beam becomes more widespread due to the spread of the line width, and the peak shape is completely deformed. However, the laser diffraction beam keeps the peak shape continuously have.

According to the results of the propagation distance of the laser beam, the shape and power density of the beam when the brittle material is processed by defocusing using the laser diffraction beam in the brittle material in the present invention The brittle material can be processed more effectively than the case of applying the Gaussian laser beam.

In addition, the concept of controlling the beam length of the laser diffraction beam in the present invention has been described with reference to FIG. 5. In the present invention, a method for further controlling the beam length of the laser diffraction beam is additionally proposed. Let's look at an example.

Fig. 7 shows a schematic diagram of a second embodiment of a laser machining apparatus for machining a brittle material according to the present invention.

In the second embodiment shown in FIG. 7, the first state 500 is formed to support the first optical system 200 and the second optical system 300 apart from each other. The first state 500 is moved along the advancing direction of the laser beam, 400 by adjusting the width of the beam.

7, the first state 500 conceptually illustrates the first state 500 in which the second optical system 300 is separated from the first optical system 200 by a predetermined distance And may be implemented in various forms such as a case or a support bar for fixing and fixing. 7, a first moving unit (not shown) may be configured to move the first state 500 along the moving direction of the laser beam, and the first moving unit may move the moving direction of the laser beam The first state 500 can be moved on the conveying rail including a parallel conveying rail and a driving device such as a motor for supporting the first state 500 along the conveying rail.

Referring to FIG. 8, the result of simulation of the beam length adjustment is shown as an example in which the length of the laser diffraction beam is adjusted according to the second embodiment of FIG. 7. In FIG. 8, The focal length F of the second optical system 300 is set to 200 mm and the focal length F of the third optical system 400 is set to 20 mm and then the first optical system 200 and the second optical system 200 A laser beam having a diameter of 4 mm was incident on the first optical system 200 while the distance A between the second optical systems 300 was fixed at 265 mm.

A ring-shaped laser diffraction beam is generated through the first optical system 200, wherein both diameters of the ring portions of the laser diffraction beam are each formed to be 2 mm and the total beam diameter of the laser diffraction beam is formed to be 8.696 mm.

8 (a), the distance B1 between the second optical system 300 and the third optical system 400 is adjusted to 240 mm through the first state 500. Accordingly, the third optical system 400 The focal length C11 of the incident beam incident on the brittle material 10 was adjusted to 0.371 mm.

8 (b), 8 (c) and 8 (d), the same laser diffraction beam as in FIG. 8 (a) is formed and the second optical system 300 and the third The distances B2, B3 and B4 between the optical systems 400 were gradually reduced to 217 mm, 210 mm and 203 mm.

As a result, the focal lengths C12, C13 and C14 of the incident beam incident on the brittle material 10 from the third optical system 400 in FIGS. 8B, 8C and 8D are 0.328 mm and 0.316 mm And 0.305 mm.

7, the distance between the second optical system 300 and the third optical system 400 can be easily controlled by keeping the spacing between the first optical system 200 and the second optical system 300 fixed through the second embodiment of FIG. The focus beam length of the incident beam can be adjusted.

9 shows a schematic diagram of a third embodiment of a laser machining apparatus for brittle material processing according to the present invention.

In the third embodiment shown in FIG. 9, the second state 600 is formed to support the second optical system 300 and the fourth optical system 400 apart from each other. Adjust the beam length by moving along.

The third state of FIG. 9 conceptually shows the second state 600 in consideration of various modifications. The second state 600 is a state in which the second optical system 300 and the third optical system 400 are separated from each other by a predetermined distance And may be implemented in various forms such as a case or a support bar for fixing and fixing. 9, a second moving unit (not shown) may be configured to move the second state 600 along the traveling direction of the laser beam, and the second moving unit may move the laser beam in a direction The second state 600 can be moved on the conveying rail including a parallel conveying rail and a driving device such as a motor for supporting the second state 600 along the conveying rail.

According to the third embodiment of FIG. 9, as the distance between the second optical system 300 and the third optical system 400 is fixed and the second state 600 moves, the distance between the first optical system 200 and the third optical system 400 2 optical system 300 can be adjusted.

Referring to FIG. 10, the simulation result of the beam length adjustment is shown as an example in which the length of the laser diffraction beam is adjusted according to the third embodiment of FIG. 9. Referring to FIG. 10, the second optical system 300 ) And the third optical system 400 are fixed at 200 mm, a laser beam having a diameter of 4 mm is incident on the first optical system 200 in the same manner as in the embodiment of FIG. 7, 2 state 600 is moved in the advancing direction of the laser beam.

10 (a), the distance A1 between the first optical system 200 and the second optical system 300 is adjusted to 264.7 mm through the second state 600, and accordingly, the third optical system The beam length C21 of the incident beam incident on the brittle material 10 was adjusted to 0.305 mm.

In FIGS. 10B, 10C and 10D, the distances A2, A3 and A4 between the first optical system 200 and the second optical system 300 through the second state 600 are 274.5 mm , 281.5 mm and 293.7 mm, respectively.

As a result, the focal lengths C22, C23 and C24 of the incident beam incident on the brittle material 10 from the third optical system 400 in FIGS. 10B, 10C and 10D are 0.290 mm and 0.277 mm And 0.255 mm.

9, the distance between the second optical system 300 and the third optical system 400 is fixed, and the distance between the first optical system 200 and the second optical system 300 can be easily The beam length of the incident beam can be adjusted.

Further, in the present invention, the beam width of the laser beam incident on the first optical system 200 may be adjusted to adjust the focal length of the incident beam incident on the brittle material. In this case, the focal length of the incident beam may be more easily adjusted The distance between the first optical system 200 and the second optical system 300 and the distance between the second optical system 300 and the third optical system 400 may be adjusted as described above.

The distance between the optical systems may be adjusted by arranging the first state 500 of FIG. 7 while adjusting the beam width of the laser beam incident on the first optical system 200, Two states 600 may be disposed to adjust the separation distance between the respective optical systems.

As a result of a simulation in which the focal length of the incident beam is adjusted by disposing the second state 600 of FIG. 9 while adjusting the beam width of the laser beam, FIG. 11 shows a laser processing apparatus for processing a brittle material according to the present invention And the length of the laser diffraction beam according to the beam width adjustment of the laser beam is adjusted.

9A to 9C, a laser processing apparatus having the same configuration as that of FIG. 9 is applied. In this case, by adjusting the beam width of the laser beam incident on the first optical system 200, The separation distance of the second optical system 300 varies depending on the different collimation positions of the beam after passing through the second optical system 200. The distance between the first optical system 200 and the second optical system 300 is controlled through the second state 600 and the distance between the second optical system 300 and the third optical system 400 is controlled through the second state 600, And a distance of 217 mm.

The widths D1, D2 and D3 of the beams incident on the first optical system 200 are adjusted to 8 mm, 6 mm and 4 mm, respectively, in FIGS. 11A, 11B and 11C, ) And the second optical system 300 were adjusted to 332.7 mm, 294.7 mm, and 264.7 mm, respectively.

As a result, the focal lengths C31, C32, and C33 of the incident beam incident on the brittle material 10 from the third optical system 400 in FIGS. 11A, 11B, and 11C are 2.169 mm and 1.627 mm and 1.084 mm, respectively.

As described above, according to the present invention, it is possible to adjust the focus beam length of the incident beam required by adjusting the width of the beam incident on the first optical system 200.

The laser machining apparatus for brittle material according to the present invention can provide a transparent brittle material having a clean machined surface free from cracks and further improve the strength. A method of processing a brittle material by using a laser processing apparatus for material processing will be described.

 12 shows a flow chart of a brittle material processing method using a filament of a laser diffraction beam according to the present invention.

Since the brittle material processing method using the laser diffraction beam filing according to the present invention uses the laser processing apparatus for brittle material according to the present invention, the laser processing apparatus for brittle material processing according to the present invention We will refer to examples as follows.

The laser generating unit 100 generates a microwave laser beam (S10), and preferably generates a microwave laser beam having a pulse width of femtosecond (FS) to picosecond (PS).

The microwave laser beam generated from the laser generator 100 is diffracted by the first optical system 200 to generate a ring-shaped laser diffraction beam in an orthogonal cross section (S20).

The laser diffraction beam from the first optical system 200 may be directly incident on the brittle material to be processed through the third optical system 300, but more preferably the laser diffraction beam from the first optical system 200 is converged or diffused And adjusts the beam length of the laser diffraction beam (S30).

Here, the beam length of the laser diffraction beam is adjusted by moving the first state 500 corresponding to the focal length of the laser diffraction beam required as shown in FIG. 8 by applying the second embodiment of FIG. 7, The length of the focus beam of the laser diffraction beam may be adjusted by adjusting the distance between the third optical system 300 and the third optical system 400, or the third state of FIG. 600 may be moved to adjust the focus beam length of the laser diffraction beam by adjusting the separation distance between the first optical system 200 and the second optical system 300. Also, the focus beam length of the diffraction beam may be adjusted as shown in FIG. 11 by selecting the width of the beam incident on the first optical system 200.

The third optical system 400 focuses the laser diffraction beam so as to focus the laser diffraction beam on the brittle material 10 to be processed. The laser beam is focused on the brittle material 10 through the third optical system 400, A laser beam is incident on the brittle material 10 (S40) by forming a focus on the air layer spaced from the upper surface.

Then, the brittle material can be processed (S50) in the brittle material 10 by the filamentation formed along the incidence direction of the laser diffraction beam.

FIG. 13 shows a glass processing result according to the prior art and a glass processing result according to the present invention. In the case of processing glass using the filament of the Gaussian laser beam according to the related art, As can be seen, it can be seen that the processed surface of the glass is not smooth and there are minute cracks. However, when the glass is processed using the laser diffraction beam filing according to the present invention, as shown in FIG. 13 (b) It can be seen that the processed surface of the glass is smooth and there is no crack.

As described above, the present invention proposes a brittle material processing method using the filament of a laser diffraction beam, which causes a filamentation phenomenon in a transparent brittle material by injecting a repetitive pulse laser, It is possible to solve the problem that the processed surface of the material is not smooth and fine cracks are generated according to the pulse interval, so that the machined surface is smooth and the crack is not generated, and furthermore, It is possible to solve the problem that the strength of the processed brittle material becomes weak due to induction of cracks from cracks when an external impact is applied.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments of the present invention are not intended to limit the scope of the present invention but to limit the scope of the present invention. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents thereof should be construed as being included in the scope of the present invention.

100: laser generating unit, 200: first optical system,
300: second optical system, 400: third optical system,
500: first state, 600: second state.

Claims (4)

A laser generator for generating a microwave pulse laser beam;
A diffraction optical system for diffracting the laser beam to generate a ring-shaped laser diffraction beam in an orthogonal cross section;
A focusing optical system for focusing the laser diffraction beam to form a focus beam before reaching the brittle material,
Wherein the focus beam is formed only between the focusing optical system and the brittle material, enters the brittle material while defocusing the focus beam, and processes the brittle material by filamentation And a laser processing device for processing a brittle material. The method according to claim 1,
Further comprising means for adjusting a width of the laser beam incident on the diffractive optical system to adjust the length of the focus beam, The method according to claim 1,
Wherein the focusing optical system includes a collimation lens for converging or diffracting the laser diffraction beam and a focusing lens for focusing the laser diffraction beam passed through the collimation lens to generate the focus beam,
Means for adjusting a distance between the collimation lens and the focusing lens, means for adjusting the distance between the collimation lens and the focusing lens, means for adjusting the distance between the collimation lens and the focusing lens, And means for adjusting the width of the laser beam. A laser beam generating step of generating a microwave pulse laser beam;
A diffraction beam generating step of diffracting the laser beam to generate a ring-shaped laser diffraction beam on an orthogonal cross section;
A focus beam forming step of focusing the laser diffraction beam through a focusing optical system and forming a focus beam only between the focusing optical system and the brittle material;
The deflected focus beam is incident on the brittle material while processing the brittle material by filamentation,
Wherein the brittle material is a brittle material.

Images