A circular processing system and method for transparent brittle materials using an ultrashort pulse laser.

Abstract

The laser circular machining system according to the present invention includes a laser unit that emits a laser beam; an optical unit positioned in the path of the laser beam that modulates the laser beam into a Bessel beam; a scan unit that reflects the Bessel beam modulated by the optical unit onto a workpiece and linearly moves the position of the Bessel beam; a focus lens that positions the focal point of the Bessel beam reflected by the scan unit onto the machining surface of the workpiece; and a micro-machining unit that moves the position of the Bessel beam in the circumferential direction to perform circular machining on the workpiece, thereby shortening the overall circular machining time.

Description

Technical Field

[0001] The present invention relates to a technique for machining a transparent and brittle material at high speed and with high precision.

[0002] More specifically, the present invention relates to a high-speed circular machining apparatus and method for a transparent and brittle material using an ultrashort pulse laser.

Background Art

[0003] Lasers are widely used for machining a workpiece (object to be machined), such as cutting the workpiece or forming a hole.

[0004] Generally, in machining using a laser, that is, laser machining, an optical element such as a lens is used to form a laser beam of a desired shape so as to be suitable for the machining operation, and the formed laser beam is irradiated onto the workpiece.

[0005] In particular, for circular machining of a brittle material that is difficult to machine, such as a transparent glass substrate, the laser beam can be used efficiently.

[0006] Korean Patent Publication No. 10-2022-0032862 (March 15, 2022, hereinafter referred to as Patent Document 1) discloses a laser machining system and method. Specifically, Patent Document 1 discloses a laser machining system including a laser unit that emits a laser beam, an optical unit that emits the laser beam as a Bessel beam, and a stage to which a workpiece to be machined with the Bessel beam is attached.

[0007] FIG. 1 schematically shows the laser machining system according to Patent Document 1.

[0008] Referring to FIG. 1, the shown laser circular machining system includes a laser unit 110 that emits a laser beam, optical units 120 and 130 that emit the laser beam as a Bessel beam, a scan unit 140, and a focus lens 150.

[0009] To create through-holes in transparent, brittle materials, the usual method involves modifying or processing a localized area with a laser, followed by chemical etching to create the holes. However, if there are particles, defects in the brittle material, or abnormal laser power in the area being processed by the laser, it becomes difficult to create holes of the desired size during etching. Etching after modifying or processing the localized area in a circular pattern significantly increases the yield because it satisfies the minimum hole size requirement.

[0010] Therefore, a method is needed to perform high-speed circular machining of tens to hundreds of micrometers. The conventional method uses a scanner to create a circular shape. Due to the thickness and size of the scanner's mirror, it operates at several Hz, which limits the ability of conventional laser machining systems to perform high-speed circular machining of tens to hundreds of micrometers. [Overview of the project] [Problems that the invention aims to solve]

[0011] The problem that this invention aims to solve is to provide a laser processing system that can process transparent, brittle materials at high speed, precisely, and finely in a circular shape by combining a single nonlinear absorption optical system, a scanning unit, and a separate micro-processing unit.

[0012] Furthermore, the problem that this invention aims to solve is to provide a circular laser processing method for transparent, brittle materials using an ultrashort pulse laser.

[0013] The problems that this invention aims to solve are not limited to the objectives mentioned above. Other objectives and advantages of this invention that are not mentioned can be understood from the following description and will become even clearer from the embodiments of this invention. Furthermore, it will be readily apparent that the objectives and advantages of this invention can be achieved by the means and combinations thereof shown in the claims. [Means for solving the problem]

[0014] To solve the aforementioned problems, an embodiment of the present invention provides a laser circular machining system for a workpiece, comprising: a laser unit that emits a laser beam; an optical unit positioned in the path of the laser beam and modulating the laser beam into a Bessel beam; a scan unit that reflects the Bessel beam modulated by the optical unit onto the workpiece and linearly moves the position of the Bessel beam; a focus lens that positions the focal point of the Bessel beam reflected by the scan unit onto the machining surface of the workpiece; and a micro-machining unit that moves the position of the Bessel beam in the circumferential direction to perform circular machining on the workpiece.

[0015] The workpiece may be made of a transparent, brittle material.

[0016] The laser unit can emit an ultrashort pulse laser beam having a pulse width of approximately 50 femtoseconds to approximately 50 picoseconds.

[0017] The ultrashort pulse laser beam may have a UV wavelength of approximately 300 nm to 400 nm, a Green wavelength of approximately 500 nm to 600 nm, or a near-infrared wavelength of approximately 900 to 1100 nm.

[0018] The optical unit may include a first lens that modulates the incident laser beam into an annular Bessel beam, and a second lens that modulates the optical axis of the Bessel beam in parallel.

[0019] The first lens may include a conical prism, an axicon lens, a DOE (Diffractive Optical Element), or an SLM (Spatial Light Modulator).

[0020] The second lens may include a sighting lens or a collimating lens.

[0021] The scanning unit may include one or more drive shafts and one or more mirrors.

[0022] The microprocessing unit may include a third lens that modulates the optical axis of an annular Bessel beam in parallel; a high-speed system composed of one or more drive shafts and mirrors that reflects the Bessel beam modulated by the third lens and adjusts the position of the Bessel beam in two or more directions; and a fourth lens that modulates the Bessel beam reflected by the high-speed system into an annular shape.

[0023] The high-speed system may include a piezo motor and / or a galvanometer.

[0024] The microprocessing unit may be disposed between the optical unit and the scanning unit and include a transmissive window whose rotation speed and tilt angle are adjusted.

[0025] The scanning unit may include one or more drive shafts and one or more mirrors.

[0026] To solve the above problems, a laser circular machining method according to an embodiment of the present invention is a laser circular machining system for a workpiece, including a laser unit that emits a laser beam; an optical unit disposed in the traveling path of the laser beam that modulates the laser beam into a Bessel beam; a scanning unit that reflects the Bessel beam modulated by the optical unit to the workpiece and linearly moves the position of the Bessel beam; a focus lens that positions the focus of the Bessel beam reflected by the scanning unit on the machining surface of the workpiece; and a microprocessing unit that moves the position of the Bessel beam in the circumferential direction to perform circular machining on the workpiece, and is a method of performing circular machining on a transparent brittle material using the laser circular machining system.

[0027] Specifically, the laser circular machining method according to an embodiment of the present invention includes: (a) aligning a laser circular machining system above a workpiece; (b) obtaining a Bessel beam by the laser circular machining system; and (c) sequentially irradiating the Bessel beam onto a plurality of through-hole forming regions of the workpiece to transform the through-hole forming regions of the workpiece and form a plurality of circular machining patterns. At this time, each circular machining pattern is formed by the micrometer machining unit, and the scanning unit moves the position from one through-hole forming region to another through-hole forming region.

[0028] The laser unit can emit an ultrashort pulse laser beam having a pulse width of about 50 femtoseconds (fs) to about 50 picoseconds (ps). Further, the laser unit can emit an ultrashort pulse laser beam having a UV wavelength of about 300 nm to 400 nm, a Green wavelength of about 500 nm to 600 nm, or a near-infrared wavelength of about 900 to 1100 nm.

[0029] The optical unit may include a first lens that modulates an incident laser beam into an annular Bessel beam and a second lens that modulates the optical axis of the Bessel beam in parallel.

[0030] The micro machining unit may include a third lens that modulates the optical axis of the annular Bessel beam in parallel; a high-speed system composed of one or more drive shafts and mirrors that reflect the Bessel beam modulated by the third lens and adjust the position of the Bessel beam in two or more directions; and a fourth lens that modulates the Bessel beam reflected by the high-speed system into an annular shape.

[0031] The high-speed system composed of one or more drive shafts and mirrors may include a piezo motor and / or a galvanometer.

[0032] The micro-machining unit may include a transmissive window positioned between the optical unit and the scanning unit, the rotation speed and tilt angle of which are adjustable.

[0033] The scan unit may include one or more drive shafts and one or more mirrors. [Effects of the Invention]

[0034] According to the circular processing system and method for transparent brittle materials using an ultrashort pulse laser according to the present invention, a scanning unit having a processing speed of several Hz and a micrometer processing unit having a processing speed of several kHz are used. The micrometer processing unit forms each circular processing pattern, and the scanning unit moves the position between the through holes. This can significantly reduce the overall time required for circular processing of transparent brittle materials.

[0035] Furthermore, according to the circular processing system and method for transparent brittle materials using an ultrashort pulse laser according to the present invention, the processing position of the workpiece can be controlled at high speed and with precision, and wet etching can be performed while the internal properties of the workpiece are locally changed or processed to have the same or similar size or shape as the through hole, thereby significantly reducing the etching time.

[0036] Furthermore, according to the circular processing system and method for transparent brittle materials using an ultrashort pulse laser according to the present invention, by using an ultrashort pulse laser, laser processing can be performed at a speed of more than 100 times faster than existing methods for forming through holes using only a scanning unit.

[0037] The effects described above, as well as the specific effects of the present invention, will be explained and described below in the following descriptions of embodiments for carrying out the invention. [Brief explanation of the drawing]

[0038] [Figure 1]This diagram schematically illustrates a conventional laser circular processing system. [Figure 2] This figure schematically shows a laser circular processing system according to an embodiment of the present invention. [Figure 3] This figure schematically shows a laser circular processing system according to another embodiment of the present invention. [Figure 4] Figure 3 shows the relationship between the window tilt angle and the circular size in micrometers in the laser circular processing system. [Figure 5] This figure schematically illustrates an example in which, when performing laser circular machining using the laser circular machining system shown in Figure 1, both the formation of the circular machining pattern and the positional movement between it and the through hole are performed by the scanning unit. [Figure 6] This figure schematically illustrates an example of laser circular machining using the laser circular machining system shown in Figure 2 or Figure 3, where a micrometer machining unit forms a circular machining pattern and a scanning unit moves the position between through holes. [Figure 7] This figure schematically illustrates a laser circular processing method according to an embodiment of the present invention. [Modes for carrying out the invention]

[0039] The advantages and features of the present invention, and the methods for achieving them, will become clear with reference to the examples described below in detail, along with the accompanying drawings. However, the present invention is not limited to the examples disclosed below, but can be embodied in a variety of different forms. These examples are provided to complete the disclosure of the present invention and to fully inform those who are ordinaryly skilled in the art to which the invention pertains, and the present invention is defined only by the scope of the claims. The same reference numerals throughout the specification refer to the same components.

[0040] To clearly illustrate the present invention in the drawings, non-explanatory parts have been omitted, and the same or similar components throughout the specification are denoted by the same reference numerals. Furthermore, the dimensions and thicknesses of each component shown in the drawings are arbitrarily shown for illustrative purposes, and the present invention is not necessarily limited to those shown.

[0041] In the entire specification, when a part is described as being "connected" to another part, this includes not only cases where it is "directly connected" but also cases where it is "indirectly connected" through other components. Furthermore, when a part is described as "containing" a component, this means, unless otherwise stated, that it does not exclude other components, but may also contain other components.

[0042] In this specification, "front" and "rear" are named based on the direction of beam propagation, with "rear" defined as the direction approaching the workpiece.

[0043] The following describes in detail a circular processing system and method for transparent brittle materials using an ultrashort pulse laser according to a preferred embodiment of the present invention, with reference to the attached drawings.

[0044] Figure 2 schematically shows a laser circular processing system according to an embodiment of the present invention.

[0045] Referring to Figure 2, the laser circular processing system shown includes a laser unit 110, optical units 120 and 130, a scan unit 140, and a focus lens 150. Each unit, including the laser unit 110 and the scan unit 140, can be controlled by a control unit. Furthermore, the micrometer processing unit 210, described later, can also be controlled by a control unit.

[0046] In the laser circular processing system, the laser beam emitted from the laser unit 110 is modulated into a Bessel beam shape via optical units 120 and 130, and the Bessel beam is irradiated onto the processing surface 101 of a workpiece fixed to a stage to process the workpiece. The Bessel beam irradiating the workpiece can process the workpiece at high speed while scanning a predetermined area of ​​the workpiece.

[0047] The laser unit 110 emits a laser beam to process a workpiece. The laser unit can generate pulsed laser light and emit it in a beam shape. Preferably, the laser unit 110 is a laser unit that emits an ultrashort pulse laser beam having a pulse width of about 50 femtoseconds to about 50 picoseconds. The ultrashort pulse laser beam may have a UV wavelength of about 300 nm to 400 nm, a Green wavelength of about 500 nm to 600 nm, or a near-infrared wavelength of about 900 to 1100 nm. Also, when viewed in the direction of propagation, the laser beam may have a circular or Gaussian beam shape.

[0048] The workpiece may be flat or plate-shaped, and may be made of a transparent, brittle material such as a glass substrate. Of course, various materials such as opaque substrates, metal materials, and semiconductor wafers can also be used as workpieces.

[0049] The optical units 120 and 130 are positioned in the path of the laser beam emitted from the laser unit 110, and are configured to cause the incident laser beam to be emitted as a Bessel beam. According to an embodiment of the present invention, the optical units 120 and 130 may include a first optical unit (or first lens) 120 and a second optical unit (second lens) 130.

[0050] The first lens 120 modulates the incident laser beam into an annular Bessel beam. The laser beam may be diffracted or refracted as it passes through the first lens 120, modulating into an annular (ring-shaped) Bessel beam (when viewed in the direction of beam propagation). The first lens 120 may include a conical prism, an axicon lens, a DOE (Diffractive Optical Element), or an SLM (Spatial Light Modulator).

[0051] The second lens 130 modulates the optical axis of the Bessel beam in parallel. The second lens 130 is positioned behind the first lens 120. The second lens 130 can limit the expansion of the Bessel beam (BL) region to suit the processing of the workpiece. The second lens 130 may include a sighting lens or a collimating lens.

[0052] According to embodiments of the present invention, the optical properties and spacing of the first lens 120 and the second lens 130 can be appropriately selected or adjusted. For example, the diameter of the Bessel beam passing through the second lens 212 may be in the range of approximately 3 to 50 mm.

[0053] After the optical axes of the Bessel beam are aligned parallel as they pass through the second lens 120, they can be incident on the scan unit 140.

[0054] The scan unit 140 reflects a Bessel beam modulated by an optical unit onto the workpiece. The scan unit 140 may include one or more drive shafts and one or more mirrors. The mirrors of the scan unit 140 can be adjusted in angle. Together, the scan unit 140 in the present invention linearly moves the position of the Bessel beam. The Bessel beam incident on the scan unit 140 is reflected by the mirrors, and the reflection angle of the reflected Bessel beam can be adjusted. For example, the scan unit 221 is a system having at least one or more drive shafts and mirrors.

[0055] The focus lens 150 positions the focal point of the Bessel beam reflected by the scan unit 140 on the workpiece surface 101. The focus lens 150 may be positioned behind the scan unit 140 or in front of the workpiece. According to an embodiment of the present invention, the focal length of the focus lens 222 may be in the range of approximately 3 to 300 mm. This allows the workpiece to be machined at a distance corresponding to the focal length of the focus lens 150.

[0056] The scan unit 140 and the focus lens 150 are used to move the focal line of the Bessel beam over the workpiece. According to an embodiment of the present invention, the focal line of the Bessel beam emitted via the scan unit 140 and the focus lens 150 can be created on the machining surface 101 of the workpiece.

[0057] On the other hand, referring to Figure 2, the laser circular processing system according to the present invention includes a micrometer processing unit 210. The micrometer processing unit 210 moves the position of the Bessel beam in the circumferential direction to perform circular processing on the workpiece.

[0058] Therefore, the micrometer processing unit 210 shown in Figure 2 includes a third optical unit (third lens) 310, a high-speed system 320 consisting of one or more drive shafts and mirrors, and a fourth optical unit (fourth lens) 330.

[0059] The third lens 310 modulates the optical axis of the annular Bessel beam in parallel. The third lens 310 is similar to the second lens 130, and the second lens 130 may include a sighting lens or a collimating lens.

[0060] The high-speed system 320 reflects the Bessel beam modulated by the third lens 310. The high-speed system 320 also adjusts the position of the Bessel beam in two or more axes.

[0061] The fourth lens 330 modulates the Bessel beam reflected by a high-speed system consisting of one or more drive axes and mirrors in an annular manner. The fourth lens, like the first lens, may be a conical prism, an axicon lens, a DOE, or a SLM.

[0062] The system shown in Figure 2 is a high-speed system consisting of one or more drive axes and mirrors, which can adjust the angle. The high-speed system consisting of one or more drive axes and mirrors may include a piezo motor and / or a galvanometer. The high-speed system may also include a steering mirror. Because the high-speed system is driven, for example, by a piezo motor, the mirrors can be moved at high speed simultaneously in the X / Y directions, and in narrow areas, it operates at several kHz, making micrometer circular machining more than 10 times faster than existing scanners. In this case, the existing scanning unit, which consists of one or more drive axes and mirrors, functions to quickly move the machining position. That is, in the existing system, a system consisting of one or more drive axes and mirrors moved the circle and the desired position, but in the present invention, a micro-machining unit is added, separating the roles of the high-speed circular machining module and the high-speed position movement. Furthermore, the high-speed system, which consists of one or more drive axes and mirrors added in this invention, draws shapes using the mirror angle, making it easier to change the size of the circle and process various shapes. This enables the processing of smaller circles at a faster speed and with greater precision, which was difficult to achieve due to the dynamic and structural characteristics of existing scanners.

[0063] Figure 3 schematically shows a laser circular processing system according to another embodiment of the present invention.

[0064] The embodiment shown in Figure 3 also includes a laser unit 110, optical units 120 and 130, a mirror unit 140, and a focusing unit 150. Since the description of Embodiment 2 can be applied almost directly to these units, a detailed explanation will be omitted.

[0065] The micrometer processing unit 210 shown in Figure 3 is positioned between the optical units 120, 130 and the scanning unit 140 and includes a transmissive window 410 whose rotational speed and tilt angle are adjustable.

[0066] The micrometer circular machining shown in Figure 3 corresponds to a method of machining circles at high speed using an optical system and a rotating axis. The micrometer circular machining unit 210 is in the form of a transmissive, flat, transmissive window 410, and by rotating it at high speed, it can achieve the same effect as a high-speed system consisting of one or more drive axes and mirrors.

[0067] This method utilizes the phenomenon where tilting a flat, transmissive window causes a shift in the parallel beam due to the refractive index (n). As shown in the example in Figure 4, the circular size (D) in micrometers can be determined by the mirror thickness (T), refractive index (n), and tilt angle (θ). The rotational speed of the axis of rotation is several kHz, and the example shown in Figure 3, like the example shown in Figure 2, enables high-speed machining.

[0068] In this case as well, the existing scan unit 140 is modified to function for high-speed positional movement.

[0069] Figure 5 schematically shows an example in which, when laser circular machining is performed using the laser circular machining system shown in Figure 1, both the formation of the circular machining pattern and the positional movement between the through-holes are performed by the scanning unit. Figure 6 schematically shows an example in which, when laser circular machining is performed using the laser circular machining system shown in Figure 2 or Figure 3, the formation of the circular machining pattern is performed by the micrometer machining unit and the positional movement between the through-holes is performed by the scanning unit.

[0070] Each circular processing pattern may be formed into a structure of multiple dot arrays.

[0071] Conventionally, as shown in the example in Figure 5, both the formation and positional movement of the circular machining pattern are performed by the scan unit 140. However, the scan unit 140 has a machining speed of several Hz, which results in a disadvantage of a slow overall machining speed.

[0072] However, in the present invention, a scan unit 140 having a processing speed of several Hz and a micrometer processing unit 210 having a processing speed of several kHz are used. The micrometer processing unit 210 forms a circular processing pattern in each through-hole forming region, and the scan unit 140 moves the position between the through-hole forming regions. This can shorten the overall time required for circular processing of transparent brittle materials.

[0073] Figure 7 schematically shows a laser circular processing method according to an embodiment of the present invention.

[0074] The laser circular machining method according to the present invention includes a laser circular machining system. The laser circular machining system utilizes a laser unit 110 that emits a laser beam; optical units 120, 130 positioned in the path of the laser beam to modulate the laser beam into a Bessel beam; a scan unit 140 that reflects the Bessel beam modulated by the optical unit onto the workpiece and linearly moves the position of the Bessel beam; a focus lens 150 that positions the focal point of the Bessel beam reflected by the scan unit onto the machining surface of the workpiece; and a micro-machining unit 210 that moves the position of the Bessel beam in the circumferential direction to perform circular machining on the workpiece.

[0075] Referring to Figure 7, the laser circular processing method according to the present invention includes an alignment step of the laser circular processing system (S710), a Bessel beam acquisition step (S720), and a circular processing pattern formation step (S730). After the circular processing pattern formation step (S730), an etching step (S740) can be performed to form through holes.

[0076] First, in the alignment stage (S710) of the laser circular machining system, the laser circular machining system is aligned above the workpiece.

[0077] Next, in the Bessel beam acquisition stage (S720), the Bessel beam is acquired through an optical unit including a first lens, a second lens, and so on.

[0078] Next, in the circular machining pattern formation stage (S730), a vessel beam is successively irradiated onto multiple through-hole formation regions of the workpiece to change the properties of the through-hole formation regions of the workpiece and form multiple circular machining patterns.

[0079] In this case, the micrometer processing unit forms each circular processing pattern, and the scanning unit moves the position from one through-hole formation region to another.

[0080] Next, in the etching stage (S740), the workpiece on which multiple circular processing patterns have been formed is etched to create multiple through holes.

[0081] Each circular processing pattern may be formed into a structure of multiple dot arrays.

[0082] In one example, the dots may be arranged at regular intervals. In other examples, the dots may be arranged at irregular intervals.

[0083] Furthermore, the dot array may, in one example, be formed in a structure where the dots are spaced apart from each other. In another example, the dot array may be formed in a structure where the dots overlap each other.

[0084] While wet etching using fluoride-based etchants, non-fluoride etchants, etc., can be used for etching, this is merely an example, and any etchant capable of etching a glass substrate can be used without limitation.

[0085] As described above, according to the circular processing system and method for transparent brittle materials using an ultrashort pulse laser according to the present invention, a scanning unit having a processing speed of several Hz and a micrometer processing unit having a processing speed of several kHz may be used. The micrometer processing unit may be used to form each circular processing pattern, and the scanning unit may be used to move the position between the through holes. This can shorten the overall time required for circular processing of transparent brittle materials.

[0086] The above description has focused on embodiments of the present invention, but various modifications and variations can be made by an engineer with ordinary skill in the art to which the present invention pertains. These modifications and variations can be said to belong to the present invention as long as they do not deviate from the scope of the technical concept provided by the present invention. Therefore, the scope of the rights of the present invention should be determined by the claims described below. [Explanation of Symbols]

[0087] 101 Machining surface 110 Laser Units 120 First optical unit (first lens) 130 Second optical unit (second lens) 140 Scan Unit (a system consisting of one or more drive axes and mirrors) 150 Focus Lens 210 micrometer machining unit 310 Third Optical Unit (Third Lens) 320 High-speed system consisting of one or more drive shafts and mirrors 330 Fourth Optical Unit (Fourth Lens)

Claims

1. A laser circular machining system for a workpiece, A laser unit that emits a laser beam; An optical unit positioned in the path of the laser beam to modulate the laser beam into a Bessel beam; A scanning unit that reflects the Bessel beam modulated by the optical unit onto the workpiece and linearly moves the position of the Bessel beam; A focus lens that positions the focal point of the Bessel beam reflected by the scan unit on the machining surface of the workpiece; and A micro-machining unit is included that moves the position of the vessel beam in the circumferential direction to perform circular machining on the workpiece. Laser circular cutting system.

2. The workpiece is a transparent, brittle material. The laser circular processing system according to claim 1.

3. The laser unit emits an ultrashort pulse laser beam having a UV wavelength of 300 nm to 400 nm, a Green wavelength of 500 nm to 600 nm, or a near-infrared wavelength of 900 to 1100 nm, and a pulse width of 50 femtoseconds to 50 picoseconds. The laser circular processing system according to claim 1.

4. The optical unit is A first lens modulates the incident laser beam into a ring-shaped Bessel beam, A second lens that modulates the optical axis of the Bessel beam in parallel, including, The laser circular processing system according to claim 1.

5. The first lens includes a conical prism, an axicon lens, a DOE (Diffractive Optical Element), or an SLM (Spatial Light Modulator). The laser circular processing system according to claim 4.

6. The second lens includes a sighting lens or a collimating lens. The laser circular processing system according to claim 4.

7. The aforementioned micro-machining unit is A third lens that modulates the optical axis of a ring-shaped Bessel beam in parallel; A high-speed system comprising one or more drive shafts and mirrors that reflects a Bessel beam modulated by the third lens and adjusts the position of the Bessel beam in two or more axes; and The high-speed system includes a fourth lens that modulates the Bessel beam reflected in an annular shape, The laser circular processing system according to claim 4.

8. The high-speed system includes a piezo motor and / or a galvanometer. The laser circular processing system according to claim 4.

9. The micro-machining unit is positioned between the optical unit and the scanning unit and includes a transmissive window whose rotational speed and tilt angle are adjustable. The laser circular processing system according to claim 4.

10. The scan unit includes one or more drive shafts and one or more mirrors. The laser circular processing system according to claim 1.

11. A method for performing circular processing on a transparent brittle material using a laser circular processing system including a micrometer processing unit and a scanning unit as described in claim 1, (a) The step of aligning the laser circular cutting system on top of the workpiece; (b) the step of obtaining a Bessel beam by the laser circular processing system; and (c) The step of sequentially irradiating the vessel beam onto multiple through-hole forming regions of the workpiece to change the shape of the through-hole forming regions of the workpiece and to form multiple circular processing patterns, The micrometer machining unit forms a circular machining pattern for each through-hole, and the scanning unit moves the position from one through-hole formation region to another. Laser circular processing method.

12. The laser unit emits an ultrashort pulse laser beam having a UV wavelength of 300 nm to 400 nm, a Green wavelength of 500 nm to 600 nm, or a near-infrared wavelength of 900 to 1100 nm, and a pulse width of 50 femtoseconds to 50 picoseconds. The laser circular processing method according to claim 11.

13. The optical unit is A first lens modulates the incident laser beam into a ring-shaped Bessel beam, A second lens that modulates the optical axis of the Bessel beam in parallel, including, The laser circular processing method according to claim 11.

14. The aforementioned micro-machining unit is A third lens that modulates the optical axis of a ring-shaped Bessel beam in parallel; A high-speed system comprising one or more drive shafts and mirrors that reflects a Bessel beam modulated by the third lens and adjusts the position of the Bessel beam in two or more axes; The system includes a fourth lens that modulates the Bessel beam reflected by the aforementioned high-speed system in an annular manner, The laser circular processing method according to claim 13.

15. The high-speed system includes a piezo motor and / or a galvanometer. The laser circular processing method according to claim 13.

16. The micro-machining unit is positioned between the optical unit and the scanning unit and includes a transmissive window whose rotational speed and tilt angle are adjustable. The laser circular processing method according to claim 13.

17. The scan unit includes a system comprising one or more drive shafts and mirrors. The laser circular processing method according to claim 11.

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