KR101582455B1 - Multi modal laser machining system - Google Patents

Abstract

SUMMARY OF THE INVENTION It is an object of the present invention to provide a multimodal laser processing apparatus configured to be easily adapted to various processing conditions according to a laser processing object and an object. More specifically, the present invention relates to a multimodal laser processing apparatus capable of switching to both a Gaussian beam or a flat top beam, facilitating adjustment of the size and shape of a beam, and checking in real time whether or not the processing is performed correctly .

Description

[0001] The present invention relates to a multi-modal laser machining system,

The present invention relates to a multimodal laser processing apparatus.

Recently, as the industries such as IT (Information Technology), NT (Nano Technology) and BT (BioTechnology) have developed, demand for small precision parts with a size of several tens of ㎛ to several tens mm has increased rapidly. Commercialization is being actively carried out. The accuracy of such precision parts is gradually decreasing to the nano level, and accordingly, methods of using MEMS and NEMS technology in the production of precision parts are spreading. When machining methods such as turning, milling, and molding are used, there is a limit that can not realize the precision required by these precision parts. Therefore, there is a demand for development of ultra precise and ultrafine technology for improving the precision It is getting higher. One such widely used technology is laser fine processing technology, and laser fine processing technology is widely used in electric, electronic, semiconductor or display industries.

Particularly, in the display industry, researches on repairing technology by using a method of removing foreign matters by using laser processing when there is a defect such as foreign matter mixing in display production process, and application to actual site Efforts are being made. As the need to improve the productivity of large-area display parts has increased recently, it has become known that repairing small-sized display parts has a more economical effect than repairing the defective parts in the case of defective parts. .

As laser processing is used in various technical fields as described above, it is difficult to cope with such a change because the laser processing apparatus is made for a single purpose. Unlike the previous one, which was enough for one function, nowadays laser machining is wider and materials and applications are also different, so one machining function is not enough.

Generally, lasers have a Gaussian beam profile whose distribution of intensity is bell-shaped, and the process is also processed into a bell-shaped form. However, there are cases where uniform machining is required depending on the material or application to be machined, and the machining shape is also variously changed, such as circular machining or square machining. Generally, to construct a Gaussian beam into a flat top beam, a diffractive optical element is designed or a special optical system is designed and applied.

KOKAI Publication No. 2004-0070158 ("Method and Apparatus for Ultra Precision Direct Patterning Using Ultrashort Pulse Laser Beam ", hereinafter referred to as prior art) discloses a beam homogenizer used to convert a Gaussian beam into a flat- / RTI > In the beam homogenizer disclosed in the prior art, a beam is incident on an optical system in which a concave lens, a splitting and condensing lens, a collimator and the like are successively arranged, and the spatial density distribution is homogeneously emitted. As described above, in order to make a Gaussian beam into a flat-top beam, a special optical system as disclosed in the prior art has been used.

Such a method is of course useful for making a Gaussian beam into a flat top beam, but it has various drawbacks such as difficulty in making a rectangular beam and difficulty in changing its size in real time. In addition, as described above, in view of recent industrial trends in which machining requirements vary widely, it is not necessary to design and change the system whenever necessary according to the machining requirements, but to change the required shape and its size in real time A method is needed.

Korean Patent Laid-Open Publication No. 2004-0070158 ("Ultra Precision Direct Patterning Method and Apparatus Using Ultrashort Pulse Laser Beam")

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a multi-modal laser processing apparatus and method capable of easily changing and applying various processing conditions according to an object to be laser- Device. More specifically, the present invention relates to a multimodal laser processing apparatus capable of switching to both a Gaussian beam or a flat top beam, facilitating adjustment of the size and shape of a beam, and checking in real time whether or not the processing is performed correctly .

According to an aspect of the present invention, there is provided a laser machining apparatus (100) for laser machining, the laser machining apparatus comprising: a laser light source (110); A mode switch 120 disposed on the optical path of the laser beam emitted from the laser light source 110 and irradiated to the object to be processed 500 so as to convert the beam profile into either a Gaussian shape or a flat top shape; An objective lens (130) for focusing the beam emitted from the mode converter (120) to a processing region of the object to be processed (500); A stage 140 on which the object to be processed 500 is placed and which is configured to be movable in x, y, and z axis directions by the controller 150; . ≪ / RTI >

At this time, the mode switch 120 includes an active slit 121 having a hole through which only a part of the laser beam traveling from the laser light source 110 passes, and the size and shape of the hole can be changed. An imaging lens 122 arranged on the optical path of the laser beam that has passed through the active slit 121 and focusing the laser beam such that the laser beam is defocused at a processing region on the object to be processed 500, ); An imaging lens moving unit 123 for changing the position of the imaging lens 122; . ≪ / RTI >

Also, the mode switch 120 switches the beam profile to a flat top shape by disposing the imaging lens 122 on the optical path of the laser beam that has passed through the active slit 121, May be configured to be driven to switch the beam profile to the Gaussian form by removing the imaging lens 122 on the optical path of the laser beam that has passed through the beam splitter 121.

In addition, the active slit 121 may include a diaphragm type in which the size of the hole is variable, a replaceable type in which a plurality of holes of different sizes and shapes are alternately arranged, a type in which the diaphragm type and the replaceable type are combined As shown in FIG.

In addition, the laser processing apparatus 100 receives a laser beam reflected from the object 500 between the mode converter 120 and the objective lens 130, An image acquiring unit 160 for acquiring images; As shown in FIG. The laser processing apparatus 100 includes an auto focusing module 167 disposed in front of a laser beam optical path incident on the image acquiring unit 160; As shown in FIG.

The laser machining apparatus 100 receives the laser beam reflected from the object to be processed 500 between the mode converter 120 and the objective lens 130 and detects the spectral spectrum of the object 500 A spectrometer 170 for measuring the intensity of light; As shown in FIG.

According to the present invention, there is a great effect that a single laser processing apparatus can be easily changed in accordance with various processing conditions, so that it is possible to easily perform processing for various requirements in one apparatus. More specifically, according to the present invention, since the Gaussian beam and the flat beam can be switched freely by using only a simple structure, the circular machining and the square machining can be performed as desired. It is advantageous that the machining area can be adjusted freely by being configured to be able to be replaced.

In addition, according to the present invention, there is a great effect that the shape being processed and the material being processed can be accurately discriminated in real time by observing the processing region using a CCD camera and a spectrometer. Accordingly, it is possible to easily and quickly grasp in real time whether the desired machining is being performed correctly during machining. By monitoring the machining situation in real time, it is possible to greatly reduce defects on the process and mass production lines It is effective.

According to the present invention, as the application fields of laser processing technology are expanded and diversified, required processing conditions are diversified, and it is possible to quickly adapt to various changing requirements even with one device Therefore, there is an effect that a much more economical production is possible than in the case where a new facility is to be provided in order to meet such a requirement in the past. In addition, as described above, in conjunction with the effect of reducing the defect rate through real-time monitoring during processing, the production efficiency and economical efficiency of the product by laser processing are greatly improved.

1 is an embodiment of a multimodal laser processing apparatus according to the present invention.
2 is a comparative example of a Gaussian profile and a flat top profile of a laser beam.
Fig. 3 is a comparative example of a result of processing with a laser beam of a Gaussian profile in laser processing and a result of processing with a laser beam of a flat-top profile. Fig.
4 is an example of beam shape modification using a slit.
FIG. 5 shows several embodiments of the hole-varying structure of the active slit of the present invention. FIG.
6 is an example of switching the profile mode in the mode converter of the multimodal laser machining apparatus of the present invention.
7 is an embodiment of a multi-modal laser processing apparatus according to the present invention;
FIG. 8 is an embodiment of the multimodal laser processing apparatus according to the present invention, which actually measures the processing spectral spectrum of the object to be processed.

Hereinafter, a multimodal laser processing apparatus according to the present invention having the above-described configuration will be described in detail with reference to the accompanying drawings.

Fig. 1 shows an embodiment of a multimodal laser processing apparatus according to the present invention. The multimodal laser processing apparatus 100 of the present invention includes a laser light source 110, a mode converter 120, an objective lens 130, a stage 140, a controller 150, and the like, as shown in FIG. . In addition, an image acquisition unit 160 and a spectrometer 170 may be further included. Here, the laser light source 110, the objective lens 130, the stage 140, and the control unit 150 are similar to those used in a general laser processing apparatus.

The laser light source 110 is a device for generating a laser to be used for processing. What material is the object to be processed 500, and what are the processing requirements, etc., can be used as appropriate. In general, nanosecond laser with pulse width of nanosecond level is widely used for laser processing. Nanosecond laser has the advantages of fast processing speed, stable and high power, and thermal deformation around processing part. And it has been pointed out that it is insufficient to be used for ultra-precision processing. In order to solve this problem, a femtosecond laser, a Atoso laser, a picosecond laser, etc., which is a pulse laser having a pulse width of femtosecond or less, are currently used in the laboratory stage. In this ultra high speed laser, Instead, it is not widely commercialized due to problems such as slow processing speed, low stability, and low power.

The objective lens 130 condenses the beam emitted from the mode converter 120 to a machining area of the object 500. As described above, the objective lens 130 focuses on the machining portion of the object to be processed 500, so that machining occurs at the portion. In FIG. 1, the beam emitted from the laser light source 110 is changed in direction by the mirror 115 to form an optical path toward the objective lens 130. However, this is merely an example, It is to be understood that the optical path may be appropriately changed by using one or more mirrors or other optical parts as necessary.

The stage 140 is placed on the object to be processed 500 and is moved by the control unit 150 in the directions of x, y, and z axes to be converged by the objective lens 130 So that the desired portion of the object 500 can be aligned with the focal point of the beam.

The control unit 150 controls the various driving units or measuring units included in the laser processing apparatus 100, including the stage 140, as described above.

The laser machining apparatus 100 of the present invention is characterized in that the profile of the laser beam can be easily changed to a Gaussian form or a flat-top form. Hereinafter, the mode converter 120 will be described. First, the difference between the beam profile and the laser processing result will be described.

Fig. 2 is a comparative example of a Gaussian profile and a flat top profile of a laser beam. Fig. 2 (A) shows a Gaussian form and Fig. 2 (B) shows a flat top form. Fig. 3 is a comparative example of a result of processing with a laser beam of a Gaussian profile in laser processing and a result of processing with a laser beam of a flat-top profile.

Actually, in the general laser processing apparatuses, the profile of the laser beam used in processing has a shape substantially as shown in FIG. 2 (A). The laser beam profile formed in this manner is called a Gaussian beam or a TEM ⁰⁰ beam. These beam profiles maintain their shape through the air or across multiple optical systems. That is, the profile of the focused beam remains in the Gaussian form even if it is smallly focused on the material surface by the lens. However, even if the laser beam is focused by a small amount due to the optical diffraction limit, it is difficult to concentrate the laser beam to a wavelength smaller than the wavelength of the laser beam to be used, and it is also difficult to process the material to a width smaller than the wavelength. When the laser beam having such a Gaussian profile is machined, it has a circular shape when viewed from the top, and a bell shape (similar to the profile) when seen from the side, as shown in Fig. 3 (A) A hole with the shape of the deepest part and the shallow part toward the edge is made.

On the other hand, as shown in FIG. 2 (B), in the case of a flat top profile having a uniform overall shape, it is possible to form a hole having a uniformly uniform depth as viewed from the side as shown in FIG. 3 (B). When making such a flat-top beam, the diameter of the Gaussian beam emitted by the laser is enlarged so as to have a larger diameter than the original diameter, passing through the optically designed optical system. In this case, unlike the Gaussian beam, when the laser intensity of the portion having a relatively high energy distribution is focused by the lens, it is difficult to maintain the flat top shape before focusing. Therefore, there is a need for an optical design that allows the flat top to come out at the desired location.

As described above, since the fields in which laser processing is applied are very wide and diversified, it is necessary to change processing shapes such as circular processing and square processing depending on the application fields in laser processing, Whether to remove the degree of removal uniformly or to remove the center deeper than the periphery may be required differently depending on the situation. Conventionally, a laser processing apparatus in which a Gaussian beam is generated is used. However, a laser processing apparatus having a special optical system for this purpose has been developed and used as a demand for a flat top beam is increased. However, conventionally, in order to enable machining with a desired machining shape and beam profile whenever necessary, the laser machining apparatus itself has to be changed, resulting in a problem that the equipment cost is excessively high.

In the case of the Gaussian beam shown in FIG. 2 (A), a circular shape similar to that shown in FIG. 3 (C) is seen from the top. When a Gaussian beam is used, Sometimes you want to get out. In addition, even if a Gaussian beam is used, it is not a clean circular shape, so another method is needed to perfectly form the circle as shown in FIG. 3 (C). Or there may be a case where it is desired to have a circular shape as shown in Fig. 3 (C) or a rectangular shape as shown in Fig. 3 (D) with a flat top beam.

In the present invention, the mode converter 120 is used to switch between the Gaussian beam and the flat top beam, and the size and shape of the beam can be easily and freely changed. That is, in order to solve various problems as described above, it is possible to easily convert a Gaussian beam and a flat top beam into a single apparatus, and more particularly, Modal laser processing apparatus having a configuration capable of easily changing the processing conditions in accordance with various needs and obtaining a flat top beam profile to a degree that meets the requirements. This will be described in more detail below.

The mode switch 120 may include an active slit 121, an imaging lens 122, and an image-forming lens moving unit 123, as in the embodiment shown in FIG. Briefly, the mode converter 120 converts the beam profile into a flat-top shape by disposing the imaging lens 122 on the optical path of the laser beam that has passed through the active slit 121, And can be driven to switch the beam profile to the Gaussian form by removing the imaging lens 122 on the optical path of the laser beam that has passed through the slit 121. [ First, each part will be described as follows.

The active slit 121 has a hole through which only a part of the laser beam traveling from the laser light source 110 passes and is formed so that the size and shape of the hole can be changed. 4 (A) and 4 (B), if the original laser beam had a relatively large diameter in the circular shape as shown on the upper side of Figs. 4 (A) and 4 (B) ), And (B), a slit having a hole for passing only a part of the slit is disposed, thereby changing the shape of the beam in a rectangular shape. Particularly, the beam size can be adjusted as desired by using a small slit as shown in Fig. 4 (A) or by using a large slit as shown in Fig. 4 (B). Of course, in the example of FIG. 4, the shape of the beam is changed to a rectangular shape by applying a square-shaped hole, but various modifications such as a circular shape and a circular shape, but the beam size may be adjusted Of course.

As described above, the active slit 121 is formed to vary the hole size and shape so that various beam shapes can be changed as desired according to requirements. Fig. 5 shows various embodiments of the hole-sloping structure of the active slit of the present invention. Fig. 5 (A) shows the aperture shape in which the hole size is variable, Fig. 5 (B) FIG. 5 (C) shows a shape in which the aperture and the replaceable shape are combined. FIG. Of course, Fig. 5 is merely an example, so that the present invention is not limited at all.

1, an active slit beam splitter 125 (see FIG. 1) is provided on the laser beam optical path between the mirror 115 and the mode switch 120 so as to add illumination to the active slit 121, And an illuminator 126 for an active slit to illuminate the active slit 121 with the active slit beam splitter 125.

The imaging lens 122 is disposed on the optical path of the laser beam that has passed through the active slit 121 so that the laser beam is defocused at a processing site on the object to be processed 500. [ It serves to concentrate the beam. Further, the imaging lens moving unit 123 serves to change the position of the imaging lens 122, more specifically, to position or remove the imaging lens 122 on the optical path of the laser beam . In the present invention, it is possible to switch from a Gaussian beam to a flat beam through placement or removal of the laser beam optical path of the imaging lens 122. The principle will be described in more detail below.

Fig. 6 shows an example of the profile mode switching in the mode converter of the multimodal laser machining apparatus of the present invention described above. 6 (B), the objective lens 130 focuses on the processing target portion of the object to be processed 500, so that a laser beam of a normal Gaussian beam Processing such as machining occurs. 6 (B)) at the machining site in Fig. 6 (B), the bell shape of the much compressed shape corresponding to the profile in the original laser beam (Fig. 6 (B) And the processing performed in this state is a processing performed in a general laser processing apparatus, that is, a laser processing using a Gaussian beam. That is, when the image forming lens 122 is removed from the laser light path in the apparatus of the present invention, the image becomes a Gaussian mode. In the Gaussian mode, when a machining shape in which the machining depth is deeper from the center and becomes shallower toward the edge is required, and a hole machining in which the cross-sectional shape of the machining shape is not so important, machining is performed with a strong intensity rather than a high precision It can be very advantageously applied when required.

6A, when the focusing lens 122 is disposed in the middle of the optical path in the state where the objective lens 130 is focused, the laser beam is focused on the focusing lens 122 The focus is formed at a position between the objective lens 130 and the object to be processed 500 and focus is defocused or defocused at the processing object 500 It happens. The profile at the focal point (Fig. 6 (A) b) shows the profile at the focal point in the Gaussian beam machining mode (except for the fact that both ends of the bell-shaped profile are partially cut by the slit) ). On the other hand, the intensity distribution is distributed to a wider range by defocusing at the machining part of the object to be processed 500, so that the profile at the machining part (Fig. 6 (A) c) Respectively.

Although this profile is not strictly a complete flat top, it is roughly flat top compared to a Gaussian beam. The original Gaussian profile is in the form of a bell, which means that the closer to the center, the closer the slope is to horizontal, and the higher the slope toward the edge. As the Gaussian profile is partially cut off at both ends by the slit and the laser beam is defocused at the machining site as described above, the intensity is distributed throughout the machined area and is much more uniform than the original Gaussian profile It becomes a rough flat top.

As a result, the laser beam having the flat top profile as shown in Fig. 6 (A) is irradiated onto the machining area of the object to be processed 500 by the defocusing. As a result, as shown in Fig. 3 (B) Can be processed more easily. Even a flat top beam, which is produced using substantially complicated optical components, does not show a perfect flat top, and even in the flat top form as in the present invention, the uniformity of the processing depth Can be achieved.

Here is another summary: In the present invention, by further arranging the imaging lens 122 on the optical path in a state in which the objective lens 130 focuses the originally machined portion, it is possible to position the objective lens 130 at any position between the objective lens 130 and the machining portion Focusing is induced and defocusing is induced at the machining area. At this time, in the course of passing through the active slit 121, the portion of the laser beam whose intensity is rapidly reduced at both ends of the profile has already been removed. As described above, by the objective lens 130 and the image forming lens 122 By defocusing at the machining site, the intensity distribution is much more flat than the normal Gaussian beam, resulting in a roughly flat top profile. When such a laser beam is machined, a corresponding level of uniformity of the machining depth can be achieved when machining is performed using a conventional flat top beam. That is, in the apparatus of the present invention, when the objective lens 130 and the imaging lens 122 are used together to perform defocusing, a flat-top mode is established. As described above, It can be very advantageously applied when uniformity is required.

Of course, the operating conditions of the multimodal laser machining apparatus 100 of the present invention are not limited only by the processing conditions of Figs. 6 (A) and 6 (B). For example, when the hole size of the active slit 121 is reduced as shown in Fig. 4 (A), a rough flat top profile is obtained. However, when the hole slit is appropriately large as shown in Fig. 4 (B) A laser beam having a size smaller than that of the laser beam of FIG. That is, in the state where the image forming lens 122 is removed on the laser beam optical path, the hole of the active slit 121 is appropriately sized as shown in FIG. 4 (B) It is possible to obtain finer processing than that processed by the Gaussian beam and to obtain a machined shape obtained by machining with a Gaussian beam. As described above, the multimodal laser machining apparatus 100 of the present invention can cope with various kinds of shapes required in laser machining through a combination of the appropriate operations of the active slit 121 and the image forming lens 122 This is a great advantage to be possible.

In addition, the multimodal laser processing apparatus 100 of the present invention receives a laser beam reflected from the object to be processed 500 between the mode converter 120 and the objective lens 130, And an image acquiring unit 160 for acquiring an image of a processing region of the image forming apparatus 500. A beam splitter 165 for an image acquisition unit is provided between the mode converter 120 and the objective lens 130 so as to transmit a reflection beam to the image acquisition unit 160. By further including the image acquisition unit 160 as described above, it is possible to intuitively determine whether or not the image is correctly processed as desired while confirming the image of the processed region directly in real time.

Fig. 7 shows an example of a processing region image acquisition of an actually processed object to be processed according to an embodiment of the multimodal laser processing apparatus of the present invention. Fig. 7 (A) shows the result of processing using a Gaussian beam, and Fig. 7 (B) shows the result of processing using a rectangular flat beam. Fig. 7 (C) is an enlarged view of a circular machining example, and Fig. 7 (D) is an enlarged view of a rectangular machining example, respectively. Fig. 7B is a result obtained by machining into a rectangular flat-top machining mode. In realizing micro-machining in the order of several micrometers, it is possible to obtain an excellent shape in which the edges of the machined portion machined into a quadrangular shape are almost linear can confirm.

The image acquiring unit 160 may be further provided with a structure for adding illumination to the image acquiring unit 160 so as to acquire images more clearly. That is, as shown in FIG. 1, an illuminator 166 may be further provided for an image acquiring unit that illuminates the image on the image acquiring unit 160 through the beam splitter 165 for the image acquiring unit. In order to obtain a clearer image, an auto focus module 167 disposed in front of the laser beam optical path incident on the image acquiring unit 160 may be further provided.

In addition, the multimodal laser processing apparatus 100 of the present invention receives a laser beam reflected from the object to be processed 500 between the mode converter 120 and the objective lens 130, And a spectrometer 170 for measuring a spectral spectrum of the sample 500. A spectrometer beam splitter 175 is provided between the mode converter 120 and the objective lens 130 so as to transmit a reflected beam to the spectrometer 170. By further including the spectrometer 170 in this way, it is possible to accurately monitor in real time whether the material is currently being processed and whether or not the process is proceeding properly in real time.

As described above, laser processing is used in a wide variety of fields. Among them, laser processing is used for manufacturing or repairing electronic parts such as display parts and semiconductor substrates. When the object to be processed 500 is an object such as a display part, a semiconductor substrate or the like, these are generally formed in the form of a laminate in which a plurality of thin films are laminated. At this time, it may be desired to process only the desired part and depth. For example, when it is desired to process only the upper thin film in the laminated body in which a plurality of thin films are stacked and to prevent the lower thin film from being damaged have. If the material being processed at this time is accurately identified in real time, ie if it is understood that the material being processed is the upper thin film material or the lower thin film material, then real time monitoring during processing may be performed to excessively damage the lower thin film The risk of forming a deep hole can be excluded more effectively.

8A and 8B show spectroscopic spectra of the processed region of the object to be processed actually measured, which is an embodiment of the multimodal laser processing apparatus according to the present invention. Fig. 8A shows the spectral spectrum of silica glass, Lt; / RTI > shows the spectral spectrum of aluminum. In this way, while the actual processing is proceeding, the material being processed is accurately grasped, and as a result, the processing precision can be further increased.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. It goes without saying that various modifications can be made.

100: Multimodal laser processing apparatus (of the present invention)
110: laser light source 115: mirror
120: Mode switch 121: Active slit
122: an image-forming lens 123: an image-
125: beam splitter for active slit 126: illumination part for active slit
130: objective lens 140: stage
150:
160: image acquisition unit 165: beam splitter for image acquisition unit
166: Illumination unit for image acquisition unit 167: Automatic focus adjustment unit
170: Spectrometer 175: Beam splitter for spectrometer
500: object to be processed

Claims (7)

1. A laser processing apparatus (100) for performing laser processing,
A laser light source 110;
A mode switch 120 disposed on the optical path of the laser beam emitted from the laser light source 110 and irradiated to the object to be processed 500 so as to convert the beam profile into either a Gaussian shape or a flat top shape;
An objective lens (130) for focusing the beam emitted from the mode converter (120) to a processing region of the object to be processed (500);
A stage 140 on which the object to be processed 500 is placed and which is configured to be movable in x, y, and z axis directions by the controller 150;
, ≪ / RTI >
The mode switch 120 includes an active slit 121 having a hole through which only a part of the laser beam traveling from the laser light source 110 passes, and the size and shape of the hole can be changed. An imaging lens 122 arranged on the optical path of the laser beam that has passed through the active slit 121 and focusing the laser beam such that the laser beam is defocused at a processing region on the object to be processed 500, ); An imaging lens moving unit 123 for changing the position of the imaging lens 122; And,
The mode converter 120 generates the defocus at the machining portion by disposing the imaging lens 122 on the optical path of the laser beam that has passed through the active slit 121 and converts the beam profile into a flat top shape And the focusing lens 122 is removed on the optical path of the laser beam that has passed through the active slit 121 to be focused so as to be focused at a machining site to be switched to a Gaussian beam profile. Modal laser processing equipment.
delete delete 2. The plasma display panel according to claim 1, wherein the active slit (121)
A diaphragm shape in which the size of the hole is variable,
A replacement type in which a plurality of holes of different sizes and shapes are alternately arranged,
The diaphragm type and the interchangeable form combined form
Wherein the laser beam is a laser beam, and the laser beam is a laser beam.
The laser machining apparatus (100) according to claim 1, wherein the laser machining apparatus
An image acquiring unit 160 that receives a laser beam reflected from the object to be processed 500 between the mode converter 120 and the objective lens 130 and captures an image of a processing region of the object 500, ;
Further comprising: a laser oscillator for generating a laser beam;
6. The laser machining apparatus (100) according to claim 5, wherein the laser machining apparatus
An auto focusing module 167 disposed in front of the laser beam optical path incident on the image acquiring unit 160;
Further comprising: a laser oscillator for generating a laser beam;
The laser machining apparatus (100) according to claim 1, wherein the laser machining apparatus
A spectrometer (170) for receiving a laser beam reflected from the object (500) between the mode converter (120) and the objective lens (130) and measuring a spectral spectrum of the object (500);
Further comprising: a laser oscillator for generating a laser beam;

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