KR20220030441A - Laser device - Google Patents

Abstract

The present invention relates to a laser apparatus. The laser apparatus comprises: a laser generator for emitting a laser beam; a beam quality factor converting unit dividing the laser beam emitted from the laser generator in the first direction crossing the emission direction to form a plurality of engraving beams, and arranging and emitting a plurality of fragment beams in the emission direction and the second direction intersecting the first direction; a telescope lens unit including a first lens array which adjusts a size of the laser beam emitted from the beam quality factor converting unit in the first direction and comprises first to n-th incident lenses, and a second lens array which has different aberration from the first lens array and comprises first to m-th output lenses (m and n are natural numbers equal to or more than 1); and a condensing lens condensing the laser beam emitted from the telescope lens unit in the first direction. An objective of the present invention is to provide the laser apparatus including the beam quality factor converting unit.

Description

LASER DEVICE

The present invention relates to a laser device, and more particularly, to a laser device including a beam quality factor converting unit.

Recently, interest in display devices has increased. Accordingly, display devices are being manufactured in various types including organic light emitting diodes (OLEDs), liquid crystal displays (LCDs), and the like.

In the display device, whether or not the pixels emit light and the degree of light emission can be controlled by using a thin film transistor. The thin film transistor may include an active layer, a gate electrode, a source electrode and a drain electrode. An oxide-based semiconductor material and/or a silicon-based semiconductor material may be used for the active layer.

Recently, polycrystalline silicon (poly-Si) obtained by crystallizing amorphous silicon (a-Si) is mainly used as a silicon-based semiconductor material. In the process of crystallizing the amorphous silicon (a-Si) into the polycrystalline silicon (poly-Si), a laser device may irradiate a laser beam onto the amorphous silicon (a-Si).

It is an object of the present invention to provide a laser device including a beam quality factor converting unit.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and may be variously expanded without departing from the spirit and scope of the present invention.

A laser device according to embodiments for realizing the object of the present invention is a laser generator for emitting a laser beam, dividing the laser beam emitted from the laser generator in a first direction intersecting the emission direction to a plurality of pieces A beam quality factor converting unit for forming beams, arranging the plurality of engraving beams in a second direction intersecting the emission direction and the first direction, and outputting the beam quality factor converting unit, the first of the laser beam emitted from the beam quality factor converting unit A first lens array including first to n-th incident lenses and a second lens array having different aberrations from the first lens array and including first to m-th output lenses for adjusting the size in the direction and a telescope lens unit (where m and n are natural numbers greater than or equal to 1) and a condensing lens for condensing the laser beam emitted from the telescope lens unit in the first direction.

In example embodiments, curvatures of the first to nth incident lenses may be the same.

In example embodiments, a curvature of at least one of the first to mth exit lenses may be different from curvatures of the other exit lenses except for the at least one exit lens.

In example embodiments, curvatures of the first to mth emitting lenses may be the same.

In example embodiments, a curvature of at least one incident lens among the first to nth incident lenses may be different from curvatures of other incident lenses except for the at least one incident lens.

In some embodiments, the thicknesses of the first to nth incident lenses may be the same.

In example embodiments, a thickness of at least one of the first to mth exit lenses may be different from thicknesses of the other exit lenses except for the at least one exit lens.

In some embodiments, the thicknesses of the first to mth emitting lenses may be the same.

In embodiments, a thickness of at least one of the first to n-th incident lenses may be different from thicknesses of the other incident lenses except for the at least one incident lens.

In embodiments, the laser beam condensed by the condensing lens may be irradiated onto a stage, and the condensing lens may be movable in a direction in which the laser beam is irradiated to the stage.

In embodiments, a homogenization unit for homogenizing the laser beam emitted from the telescope lens unit in the second direction may be further included.

In embodiments, the beam quality factor converting unit may output the laser beam by converting a size in the first direction and a size in the second direction.

In embodiments, the beam quality factor converter may change a beam quality factor in the first direction and a beam quality factor in the second direction of the laser beam.

In embodiments, a beam splitter may further include a beam splitter for splitting the laser beam emitted from the beam quality factor converting unit and emitting it to the telescope lens unit.

In embodiments, a beam mirror that reflects the laser beam emitted from the beam quality factor converting unit and output to the telescope lens unit may be further included.

A laser device according to embodiments for realizing the object of the present invention is a laser generator for emitting a laser beam, dividing the laser beam emitted from the laser generator in a first direction intersecting the emission direction to a plurality of pieces A beam quality factor converting unit for forming beams, arranging the plurality of engraving beams in a second direction intersecting the emission direction and the first direction, and outputting the beam quality factor converting unit, the first of the laser beam emitted from the beam quality factor converting unit A telescope lens unit ( However, k is a natural number equal to or greater than 2) and a condensing lens for condensing the laser beam emitted from the telescope lens unit in the first direction.

In embodiments, the first to kth incident lenses and the first to kth output lenses are disposed to face each other, and the first to kth incident lenses and the first to kth exit lenses At least one of the distances separated from each other may be different from other distances except for the at least one distance.

In embodiments, the laser beam condensed by the condensing lens may be irradiated onto a stage, and the condensing lens may be movable in a direction in which the laser beam is irradiated to the stage.

In embodiments, a homogenization unit for homogenizing the laser beam emitted from the telescope lens unit in the second direction may be further included.

In embodiments, the beam quality factor converting unit changes the beam quality factor in the first direction and the beam quality factor in the second direction of the laser beam, the size of the laser beam in the first direction and the second direction It can be emitted by changing the size in two directions.

A laser device according to embodiments of the present invention may include a beam quality factor converting unit and a telescope lens unit. The telescope lens unit may include a first lens array and a second lens array having a different aberration from the first lens array. Alternatively, each of the lenses of the first lens array and each of the lenses of the second lens array may be disposed at different intervals from each other.

Accordingly, the laser device may emit a homogeneous laser beam by adjusting a position at which a focus of the laser beam is formed. The laser device can effectively crystallize amorphous silicon.

In addition, the laser beam can be homogenized in the short axis direction without the homogenizer in the short axis direction due to the beam quality factor converting unit and the telescope lens unit.

However, the effects of the present invention are not limited to the above effects, and may be variously expanded without departing from the spirit and scope of the present invention.

1 is a plan view illustrating a display device according to an exemplary embodiment.
FIG. 2 is a cross-sectional view showing an embodiment taken along line I-I' of FIG. 1 .
3 is a flowchart illustrating a movement path of a laser beam emitted from a laser device according to an embodiment of the present invention.
4 is a perspective view illustrating a laser device according to an embodiment of the present invention.
5 is a schematic diagram illustrating an embodiment of a laser beam passing through a beam quality factor converting unit.
6A and 6B are diagrams illustrating an embodiment of the beam quality factor changing unit of FIG. 5 .
7 and 8 are diagrams illustrating an embodiment in which a laser beam is divided by a beam quality factor converting unit.
9 is a block diagram illustrating an embodiment of a telescope lens unit.
10A, 10B, and 10C are cross-sectional views illustrating embodiments of lenses included in a telescope lens unit.
11 is a plan view illustrating an embodiment of a homogenizer.
12 is a block diagram illustrating an embodiment of a telescope lens unit.
13 is a view showing an embodiment of a cross-section in the short axis direction of a laser beam emitted from the laser device according to the present invention.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. The same reference numerals are used for the same components in the drawings, and duplicate descriptions of the same components will be omitted.

1 is a plan view illustrating a display device according to an exemplary embodiment.

Referring to FIG. 1 , the display device DD may include a display area DA and a non-display area NDA. The non-display area NDA may surround the display area DA.

A plurality of pixels P may be disposed in the display area DA. The plurality of pixels P may be generally disposed in the display area DA. For example, the plurality of pixels P may be disposed in the display area DA in a matrix form. However, this is an example, and the arrangement of the plurality of pixels P is not limited thereto.

The display device DD may display a moving image or a still image through the display area DA. A driver for driving the display area DA may be disposed in the non-display area NDA. Although the display device DD is illustrated in a rectangular shape, the present invention is not limited thereto. For example, the display device DD may have a shape such as a long rectangle, a square, a rectangle with rounded corners (vertices), other polygons, or a circle.

FIG. 2 is a cross-sectional view showing an embodiment taken along line I-I' of FIG. 1 .

Referring to FIG. 2 , the display device DD includes a substrate 10 , a buffer layer 15 , a first gate insulating layer 20 , a first interlayer insulating layer 25 , a second interlayer insulating layer 30 , The second gate insulating layer 35 , the third interlayer insulating layer 40 , the via insulating layer 45 , the pixel defining layer PDL, the first transistor TFT1 , the second transistor TFT2 , and the organic light emitting diode ( OLED) may be included. The first transistor TFT1 may include a first active layer 17 , a first gate electrode 23 , a capacitance electrode 27 , a first source electrode 41 , and a first drain electrode 42 . . The second transistor TFT2 may include a second active layer 33 , a second gate electrode 37 , a second source electrode 43 , and a second drain electrode 44 . The organic light emitting diode OLED may include a lower electrode 50 , an emission layer 55 , and an upper electrode 60 .

The substrate 10 may support layers disposed thereon. The substrate 10 may be made of an insulating material such as a polymer resin or an inorganic material such as glass or quartz.

A buffer layer 15 may be disposed on the substrate 10 . The buffer layer 15 may prevent impurities from penetrating into the first and second transistors TFT1 and TFT2 . Alternatively, the buffer layer 15 may planarize the substrate 10 when the substrate 10 is not flat. The buffer layer 15 may include silicon nitride, silicon oxide, or silicon oxynitride.

The first active layer 17 may be disposed on the buffer layer 15 . The first active layer 17 may serve as a channel of the first transistor TFT1 . The first active layer 17 may include a silicon-based semiconductor material. In embodiments, the silicon-based semiconductor material may be polycrystalline silicon obtained by crystallizing amorphous silicon. A crystallization process using a laser beam may be performed to crystallize the amorphous silicon. In order to improve the performance of the first transistor TFT1, the crystallization process of the first active layer 17 needs to be effectively performed. To this end, the laser beam used in the crystallization process must have high homogeneity.

The first gate insulating layer 20 may be disposed on the first active layer 17 . The first gate insulating layer 20 may include a silicon compound, a metal oxide, or the like.

The first gate electrode 23 may be disposed on the first gate insulating layer 20 . The first gate electrode 23 may receive a gate signal input by the driver. To this end, the first gate electrode 23 may include a metal, an alloy, a metal nitride, a conductive metal oxide, a transparent conductive material, or the like.

The first interlayer insulating layer 25 may be disposed on the first gate electrode 23 . The first interlayer insulating layer 25 may include a silicon compound, a metal oxide, or the like.

The capacitance electrode 27 may be disposed on the first interlayer insulating layer 25 . The capacitance electrode 27 may form a capacitor together with the first gate electrode 23 .

The second interlayer insulating layer 30 may be disposed on the capacitance electrode 27 . The second interlayer insulating layer 30 may include a silicon compound, a metal oxide, or the like.

The second active layer 33 may be disposed on the second interlayer insulating layer 30 . The second active layer 33 may serve as a channel of the second transistor TFT2 . The second active layer 33 may include an oxide-based semiconductor material.

The second gate insulating layer 35 may be disposed on the second active layer 33 . The second gate insulating layer 35 may include a silicon compound, a metal oxide, or the like.

The second gate electrode 37 may be disposed on the second gate insulating layer 35 . The second gate electrode 37 may receive a gate signal input by the driver. To this end, the second gate electrode 37 may include a metal, an alloy, a metal nitride, a conductive metal oxide, a transparent conductive material, or the like.

The second interlayer insulating layer 40 may be disposed on the second gate electrode 37 . The second interlayer insulating layer 40 may include a silicon compound, a metal oxide, or the like.

The first source electrode 41 , the second source electrode 43 , the first drain electrode 42 , and the second drain electrode 44 may be disposed on the second interlayer insulating layer 40 . . The first source electrode 41 and the first drain electrode 42 may be connected to the first active layer 17 through a contact hole. The second source electrode 43 and the second drain electrode 44 may be connected to the second active layer 33 through a contact hole. The source electrodes 41 and 43 and the drain electrodes 42 and 44 may include a conductive material such as molybdenum (Mo), copper (Cu), aluminum (Al), or titanium (Ti). .

The via insulating layer 45 may be disposed on the source electrodes 41 and 43 and the drain electrodes 42 and 44 . The via insulating layer 45 may include an organic insulating material such as polyimide (PI).

The lower electrode 50 may be disposed on the via insulating layer 45 . The lower electrode 50 may be connected to the first drain electrode 42 through a contact hole. The lower electrode 50 may include a conductive material such as a metal, an alloy, or a transparent conductive oxide.

The pixel defining layer PDL may be disposed on the via insulating layer 45 . The pixel defining layer PDL may cover a portion of the lower electrode 50 and may have an opening exposing a top surface of the lower electrode 50 . The pixel defining layer PDL may be formed of an organic insulating material such as polyimide PI.

The emission layer 55 may be disposed on the lower electrode 50 . The emission layer 55 may be disposed on the lower electrode 50 exposed by the opening. In some embodiments, the light emitting layer 55 may include at least one of an organic light emitting material and quantum dots.

The upper electrode 60 may be disposed on the emission layer 55 . In some embodiments, the upper electrode 60 may also be disposed on the pixel defining layer PDL. The upper electrode 60 may be formed of a conductive material such as a metal, an alloy, or a transparent conductive oxide. For example, the conductive material includes aluminum (Al), platinum (Pt), silver (Ag), magnesium (Mg), gold (Au), chromium (Cr), tungsten (W), titanium (Ti), etc. can do.

3 is a flowchart illustrating a movement path of a laser beam emitted from a laser device according to an embodiment of the present invention. In embodiments, the laser device of FIG. 3 may be used to crystallize the first active layer 17 of FIG. 2 .

Referring to FIG. 3 , the laser device LD may include a laser generator 100 , a beam quality factor converting unit 200 , a telescope lens unit 300 , a homogenizing unit 400 , and a condensing lens 500 . . The laser beam LB emitted from the laser device LD may be irradiated onto the stage 600 .

The laser generator 100 may emit a first laser beam LB1 . The laser generator 100 may emit at least one first laser beam LB1. For example, the laser generator 100 may emit one first laser beam LB1 or two or more first laser beams LB1 as needed. The first laser beam LB1 may have straightness. The first laser beam LB1 may form a beam spot on the irradiation surface. The first laser beam LB1 may have a Gaussian type energy distribution having high energy in the center thereof.

In embodiments, the laser generator 100 may emit an excimer laser beam, a YAG laser beam, a glass laser beam, a YVO4 laser beam, an Ar laser beam, a ruby laser beam, or the like. However, the present invention is not limited thereto, and the laser generator 100 may emit various laser beams capable of crystallizing amorphous silicon in addition to the above-described laser beams.

The beam quality factor converting unit 200 may output the first laser beam LB1 by converting the major axis size and the minor axis size. A major axis and a minor axis of the first laser beam LB1 may be perpendicular to each other. In some embodiments, the beam quality factor converting unit 200 may change the beam quality factor in the long axis direction and the beam quality factor in the short axis direction of the first laser beam LB1 . The beam quality factor converting unit 200 may improve the homogeneity of the first laser beam LB1 . The beam quality factor conversion unit 200 may emit the second laser beam LB2 obtained by converting the major axis size and the minor axis size of the first laser beam LB1 .

), 렌즈에 입사되는 레이저 빔의 사이즈(D), 렌즈의 초점거리(F)와 빔질 인자(M²; beam quality factor)의 관계를 통하여 다음의 [식 1]에 의해 결정될 수 있다.In general, the laser beam may proceed in a Gaussian shape. The spot size (2w ₀ ) of the laser beam may be defined as a size corresponding to twice the radius (w ₀ ) at the beam waist. The beam waist may mean a region in which the diameter of the first laser beam reaches a minimum value due to diffraction of the laser beam. The spot size (2w ₀ ) is the wavelength of the laser beam (

), the size of the laser beam incident on the lens (D), the focal length of the lens (F), and the beam quality factor (M ² ; beam quality factor) can be determined by the following [Equation 1].

[Equation 1]

Referring to Equation 1, if the beam quality factor M ² is reduced while maintaining the size D of the laser beam and the focal length F of the lens, the spot size 2w ₀ may be reduced. The beam quality factor (M ² ) is a quantitative quantification of the condensing characteristics of the laser beam, and may be a measure indicating the degree of change from the ideal Gaussian type laser beam. The beam quality factor (M ² ) may be ideal as it is closer to 1. The beam quality factor M ² may have various values according to directions. For example, the laser beam may have a major axis in an x-axis direction and a minor axis in a y-axis direction perpendicular to the x-axis. In this case, the laser beam may have a major axis beam quality factor (Mx ² ) with respect to the major axis direction and a minor axis beam quality factor (My ² ) with respect to the minor axis direction. For example, the long axis beam quality factor (Mx ² ) and the short axis beam quality factor (My ² ) may not change even if the size of the laser beam is simply enlarged or reduced. The long axis beam quality factor Mx ² and the short axis beam quality factor My ² may be changed when the laser beam is rearranged by the beam quality factor conversion unit 200 .

In some embodiments, the telescope lens unit 300 may adjust the minor axis size of the second laser beam LB2 . For example, the telescope lens unit 300 may increase or decrease the minor axis size of the second laser beam LB2 . The telescope lens unit 300 may include a plurality of lenses. The telescope lens unit 300 may emit the third laser beam LB3 in which the minor axis size of the second laser beam LB2 is adjusted.

In some embodiments, the homogenizer 400 may homogenize the third laser beam LB3 in the long axis direction. The homogenizer 400 may include a homogenizing lens, a condenser lens, and the like. The homogenizing lens may include a plurality of lenses. The homogenizer 400 may emit the fourth laser beam LB4 obtained by homogenizing the third laser beam LB3 in the long axis direction.

The condensing lens 500 may focus the fourth laser beam LB4 in the short axis direction before the fourth laser beam LB4 is irradiated onto the stage 600 . The condensing lens 500 may condense the fourth laser beam LB4 to increase energy density. The condensing lens 500 may emit a laser beam LB.

4 is a perspective view illustrating a laser device according to an embodiment of the present invention.

Referring to FIG. 4 , an amorphous silicon thin film 610 may be disposed on the stage 600 . The amorphous silicon thin film 610 may not be disposed alone, but may be disposed on the stage 600 together with a separate configuration. For example, the amorphous silicon thin film 610 may be disposed on the stage 600 while disposed on the substrate 10 . The material crystallized by the laser device LD is not limited to the amorphous silicon thin film 610 . For example, the material may be an amorphous semiconductor layer further including a material other than silicon.

The laser device LD may radiate a laser beam LB onto the amorphous silicon thin film 610 . For example, the laser device LD may radiate the laser beam LB while moving in the second direction DR2 . Alternatively, in the laser device LD, the stage 600 may move in a direction opposite to the second direction DR2 and the laser device LD may irradiate the laser beam LB in a fixed state. there is.

The amorphous silicon thin film 610 may be crystallized into a polycrystalline silicon thin film 620 by a laser beam LB. For example, the polysilicon thin film 620 may correspond to the first active layer 17 . A large amount of energy may be required for effective crystallization of the amorphous silicon thin film 610 . Accordingly, it may be preferable that the energy provided per unit area of the area to which the laser beam LB is irradiated increases. In addition, for effective crystallization of the amorphous silicon thin film 610, a homogeneous laser beam LB needs to be irradiated.

The laser beam LB may be emitted in the form of a line extending in one direction. In some embodiments, the laser beam LB may be emitted in a third direction DR3 perpendicular to the second direction DR2 . A line shape of the laser beam LB may extend in a first direction DR1 perpendicular to the third direction DR3 and the second direction DR2 that are the emission directions. The first direction DR1 may be a long axis direction of the laser beam LB. A length of the laser beam LB in the long axis direction may be defined as a major axis size Dx. The laser device LD may crystallize a larger area of the amorphous silicon thin film 610 at a time as the long axis size Dx increases. The major axis size Dx may be determined by optical systems included in the laser device LD.

Also, the second direction DR2 may be a short axis direction of the laser beam LB. The length of the laser beam LB in the minor axis direction may be defined as a minor axis size Dy. The laser device LD may effectively irradiate the amorphous silicon thin film 610 with greater energy per unit area as the minor axis size Dy is smaller.

The laser beam LB emitted from the laser device LD may provide the largest energy at a focal point. Accordingly, the focus of the laser beam LB may be preferably formed inside the amorphous silicon thin film 610 for effective crystallization of silicon. For example, the focal point of the laser beam LB may be located at the center in the thickness direction inside the amorphous silicon thin film 610 , but is not limited thereto. The focus of the laser beam LB may be shifted from the center of the amorphous silicon thin film 610 in the thickness direction to one side or the other side of the third direction DR3.

In some embodiments, the laser device LD may move in the third direction DR3 to adjust a position of a focal point of the laser beam LB formed on the amorphous silicon thin film 610 . Through this, the distance between the condensing lens for increasing the energy density of the laser beam LB and the stage 600 before the laser beam LB is irradiated may be adjusted. Alternatively, in some embodiments, the stage 600 may move in the third direction DR3 to adjust the position of the focus.

5 is a schematic diagram showing an embodiment of a laser beam passing through a beam quality factor converting unit, FIGS. 6A and 6B are diagrams showing an embodiment of the beam quality factor changing unit of FIG. 5, and FIGS. 7 and 8 are beam quality factor conversion It is a drawing showing an embodiment in which a laser beam is divided by a part.

3, 5, 6A, 6B, 7 and 8 , the first laser beam LB1 emitted from the laser generator 100 is the beam quality factor along the third direction DR3. It may be incident to the conversion unit 200 . In this case, the first laser beam LB1 may have a minor axis size Dx1 and a long axis size Dy1 . The line-shaped first laser beam LB1 extending in the second direction DR2 is a line-shaped second laser beam LB2 extending in the first direction DR1 by the beam quality factor converting unit 200 . ) can be emitted.

In some embodiments, the beam quality factor converter 200 may repeatedly reflect the first laser beam LB1 . The beam quality factor converting unit 200 may sequentially emit engraving beams of a predetermined size by dividing the reflected first laser beam LB1 by moving the position by a predetermined distance. To this end, the beam quality factor converter 200 may include a plurality of mirrors. The mirrors may be disposed on the first sidewall 210 and the second sidewall 220 in the beam quality factor converter 200 .

In some embodiments, the beam quality factor converter 200 may not be perpendicular to the third direction DR3 . For example, the first sidewall 210 and the second sidewall 220 may not be perpendicular to the third direction DR3 . In other words, the beam quality factor converting unit 200 may be rotated based on a virtual axis formed in the second direction DR2. Through this, the first laser beam LB1 incident to the beam quality factor converting unit 200 is reflected by the mirrors disposed on the first sidewall 210 and the second sidewall 220 in the first direction. It can move in the opposite direction to (DR1). Accordingly, a length of the second laser beam LB2 in the first direction DR1 may be longer than a length of the first laser beam LB1 in the first direction DR1 .

Also, the beam quality factor converting unit 200 may be rotated based on a virtual axis extending in the first direction DR1 . Through this, the first laser beam LB1 incident to the beam quality factor converting unit 200 is reflected by the mirrors disposed on the first sidewall 210 and the second sidewall 220 in the second direction. It can move in the opposite direction to (DR2). Accordingly, a length of the second laser beam LB2 in the second direction DR2 may be shorter than a length of the first laser beam LB1 in the second direction DR2 .

For example, the beam quality factor converter 200 may split the first laser beam LB1 into six engraving beams in the second direction DR2 . The beam quality factor converter 200 may arrange the divided six engraving beams in the first direction DR1 to emit the second laser beam LB2 .

Through this, the beam quality factor converting unit 200 may change the long axis beam quality factor Mx ² and the short axis beam quality factor My ² of the first laser beam LB1 . Also, the beam quality factor converting unit 200 may convert the major axis sizes Dx1 and Dx2 and the minor axis sizes Dy1 and Dy2 of the first laser beam LB1 .

9 is a block diagram illustrating an embodiment of a telescope lens unit, and FIGS. 10A, 10B and 10C are cross-sectional views illustrating embodiments of lenses included in the telescope lens unit.

3, 9, and 10A, 10B, and 10C , the telescope lens unit 300 may adjust the size of the second laser beam LB2. In some embodiments, the telescope lens unit 300 may adjust the size of the second laser beam LB2 in the minor axis direction. The telescope lens unit 300 may include a first lens array 310 and a second lens array 320 .

The first lens array 310 may include first to n-th incident lenses 310a to 310n (where n is a natural number equal to or greater than 2). In some embodiments, the first to n-th incident lenses 310a to 310n may have a convex incident surface and a flat exit surface. The second laser beam LB2 may be refracted in the second direction DR2 in the first to n-th incident lenses 310a to 310n to be focused on a focal point and then dispersed. In some embodiments, the first to nth incident lenses 310a to 310n may be disposed to be spaced apart from each other in the first direction DR1 .

In some embodiments, the laser device LD may further include a beam splitter for splitting the second laser beam LB2 . In addition, it may further include a beam mirror (beam mirror) for changing the traveling path of the divided second laser beam (LB2). Through this, the second laser beam LB2 may be incident on the first to nth incident lenses 310a to 310n, respectively.

In embodiments, when there are a plurality of laser beams emitted from the laser generator 100 , the plurality of second laser beams LB2 are formed by the first to nth incident lenses without using the beam splitter and the beam mirror. They may be incident to each of the fields 310a to 310n.

The second lens array 320 may include the first to mth output lenses 320a to 320m (where m is a natural number equal to or greater than 2). In some embodiments, an incident surface of the first to m-th output lenses 320a to 320n may be flat, and an exit surface may have a convex shape. The second laser beam LB2 may be refracted by the first to nth incident lenses 310a to 310n. The first to m-th emitting lenses 320a to 320n refract the second laser beam LB2 that is diffused in the second direction DR2 to form a third laser beam parallel to the third direction DR3 ( LB3) can be emitted. A size of the third laser beam LB3 in the second direction DR2 may be different from a size of the second laser beam LB2 in the second direction DR2 . In some embodiments, the first to mth emitting lenses 320a to 320m may be disposed to be spaced apart from each other in the first direction DR1 .

In some embodiments, the aberrations of the first to nth incident lenses 310a to 310n may be different from the aberrations of the first to mth exit lenses 320a to 320m. The aberration may be different depending on the thickness, curvature, etc. of each lens.

In some embodiments, the number of the first to nth incident lenses 310a to 310n and the number of the first to mth exit lenses 320a to 320m may not be the same. The laser device LD may further include the beam splitter and the beam mirror. Through this, all of the second laser beams LB2 emitted from the first to nth incident lenses 310a to 310n may be incident to the first to mth incident lenses 320a to 320m.

In some embodiments, the lenses may have a length in the second direction DR2 and a thickness in the third direction DR3 .

As such, the telescope lens unit 300 may adjust the size of the laser beam in the second direction DR2 and maintain the same size in the first direction DR1 .

In some embodiments, the curvatures of each of the first to nth incident lenses 310a to 310n may be the same. A curvature of at least one of the first to mth exit lenses 320a to 320m may be different from curvatures of the other exit lenses. The telescope lens unit 300 may adjust the aberration in the second direction DR2 as the curvature of at least one output lens is different. Through this, the position at which the focus of the third laser beam LB3 passing through the telescope lens unit 300 is formed can be differently adjusted to improve the homogeneity of the third laser beam LB3.

In some embodiments, curvatures of the first to mth emitting lenses 320a to 320m may be the same. A curvature of at least one of the first to nth incident lenses 310a to 310n may be different from curvatures of the other incident lenses. The telescope lens unit 300 may adjust the aberration in the second direction DR2 as the curvature of at least one incident lens is different. Through this, the position at which the focus of the third laser beam LB3 passing through the telescope lens unit 300 is formed can be differently adjusted to improve the homogeneity of the third laser beam LB3.

In some embodiments, the thicknesses of each of the first to nth incident lenses 310a to 310n may be the same. A thickness of at least one of the first to mth output lenses 320a to 320m may be different from thicknesses of the other output lenses. The telescope lens unit 300 may adjust the aberration in the second direction DR2 as the thickness of the at least one exit lens is different. Through this, the position at which the focus of the third laser beam LB3 passing through the telescope lens unit 300 is formed can be differently adjusted to improve the homogeneity of the third laser beam LB3.

In some embodiments, the thicknesses of each of the first to mth emitting lenses 320a to 320m may be the same. A thickness of at least one of the first to nth incident lenses 310a to 310n may be different from thicknesses of the other incident lenses. The telescope lens unit 300 may adjust the aberration in the second direction DR2 as the thickness of at least one incident lens is different. Through this, the position at which the focus of the third laser beam LB3 passing through the telescope lens unit 300 is formed can be differently adjusted to improve the homogeneity of the third laser beam LB3.

However, this is an example, and the telescope lens unit 300 uses lenses having different thicknesses and different curvatures at the same time, thereby differently adjusting the position at which the focus of the third laser beam LB3 is formed, and thus the third laser beam LB3 ) can improve the homogeneity of

Although it is illustrated that the size of the second direction DR2 of the second laser beam LB2 increases in FIG. 10A , this is exemplary and is not limited thereto. For example, the size of the second laser beam LB2 in the second direction DR2 may decrease after passing through the telescope lens unit 300 .

In addition, although it is illustrated that the lenses 310a and 320a are spaced apart by a first distance a in FIG. 10A , this is exemplary and is not limited thereto. For example, as shown in FIG. 10B , the lenses 310a and 320a may be spaced apart by a second distance b that is shorter than the first distance a. In this case, the size of the third laser beam LB emitted from the first exit lens 320a may increase in the second direction DR2 as it travels in the third direction DR3 .

Also, as illustrated in FIG. 10C , the lenses 310a and 320a may be spaced apart from each other by a third distance c that is longer than the first distance a. In this case, the size of the third laser beam LB emitted from the first exit lens 320a may decrease in the second direction DR2 as it travels in the third direction DR3. FIG. 11 is a plan view showing an embodiment of the homogenizer.

3 and 11 , the homogenizing unit 400 may include a first homogenizing lens 410 , a second homogenizing lens 420 , and a condenser lens 430 . The homogenizer 400 may receive the third laser beam LB3 having a Gaussian energy distribution in the first direction DR1 and homogenize it in the first direction DR1 .

An incident surface of the first homogenizing lens 410 may be convex, and an exit surface may be flat. The first homogenizing lens 410 may have a structure in which a plurality of lenses are continuously connected. The third laser beam LB3 may be refracted by the first homogenizing lens 410 .

A second homogenizing lens 420 may be disposed on the rear surface of the first homogenizing lens 410 . The second homogenizing lens 420 may have a flat incident surface and a convex exit surface. The second homogenizing lens 420 may have a structure in which a plurality of lenses are continuously connected. A focal point of the first homogenizing lens 410 may be formed between the first homogenizing lens 410 and the second homogenizing lens 420 . However, in embodiments, the focus of the first homogenizing lens 410 may be formed inside the second homogenizing lens 420 or may be formed past the second homogenizing lens 420 . The third laser beam LB3 refracted by the first homogenizing lens 410 may be focused on the focus of the first homogenizing lens 410 and then dispersed again to be incident on the second homogenizing lens 420 . .

The condenser lens 430 may be disposed on the rear surface of the second homogenizing lens 420 . An incident surface of the condenser lens 430 may be flat, and an exit surface of the condenser lens 430 may be convex. The condenser lens 430 may refract the third laser beam LB3 diffused in the first direction DR1 to be emitted as a fourth laser beam LB4 parallel to the third direction DR3 . The fourth laser beam LB4 emitted from the condenser lens 430 may have a uniform energy distribution in the first direction DR1 .

In some embodiments, the size of the third laser beam LB3 in the first direction DR1 may be larger than the size of the fourth laser beam LB4 in the first direction DR1 .

The fourth laser beam LB4 emitted from the homogenizer 400 may be incident on the condensing lens 500 . In some embodiments, the fourth laser beam LB4 emitted from the homogenizer 400 may be incident on the condensing lens 500 through the beam mirror and/or the beam splitter. The condensing lens 500 may reduce the size of the fourth laser beam LB4 in the second direction DR2 . Through this, the condensing lens 500 may improve the energy density of the laser beam LB4.

12 is a block diagram illustrating an embodiment of a telescope lens unit.

3 and 12 , the telescope lens unit 300 may include a third lens array 330 and a fourth lens array 340 . The third lens array may include first to kth incident lenses 330a to 330k. Also, the telescope lens unit 300 may include first to k-th output lenses 340a to 340k (where k is a natural number equal to or greater than 2).

In some embodiments, the curvature and thickness of each of the first to kth incident lenses 330a to 330k and the first to kth exit lenses 340a to 340k may be the same. The telescope lens unit 300 adjusts the distances between the first to k-th incident lenses 330a to 330k and the first to k-th output lenses 340a to 340k to adjust the distances between the telescope lens unit ( The homogeneity of the third laser beam LB3 emitted from 300 may be improved.

In some embodiments, the first to k-th incident lenses 330a to 330k and the first to k-th output lenses 340a to 340k may be disposed to face each other. For example, the p-th incident lens 330a and the p-th exit lens 340a may be disposed to face each other (provided that p is a natural number equal to or greater than 1 and less than or equal to k).

In embodiments, at least one of the distances at which the first to k-th incident lenses 330a to 330k and the first to k-th output lenses 340a to 340k are spaced apart from each other is the at least one It may be different from other distances except for the distance. For example, a distance between the first incident lens 330a and the first output lens 340a may be different from a distance between the second incident lens 330b and the second exit lens 340b. Through this, the position at which the focus of the third laser beam LB3 passing through the telescope lens unit 300 is formed can be differently adjusted to improve the homogeneity of the third laser beam LB3.

As described above, the laser device LD according to the present invention may lower the beam quality factor in the short axis direction of the laser beam through the beam quality factor converting unit 200 . Accordingly, the laser device LD may improve the homogeneity of the laser beam in the minor axis direction.

In addition, since the telescope corrector 300 includes lenses having different aberrations, it is possible to differently adjust a position where the focus of the laser beam emitted from the telescope corrector 300 is formed. Through this, the laser device LD may achieve homogenization of the laser beam in the short axis direction. Accordingly, the laser device LD may achieve homogenization of the laser beam without the homogenization unit in the minor axis direction.

13 is a diagram illustrating an embodiment of a cross-section in a short axis direction of a laser beam emitted from a laser device according to the present invention.

Referring to FIG. 13 , the laser apparatus according to embodiments of the present invention may include a beam quality factor converting unit and a telescope lens unit. The telescope lens unit may include a first lens array and a second lens array having a different aberration from the first lens array. Alternatively, each of the lenses of the first lens array and each of the lenses of the second lens array may be disposed at different intervals from each other.

Accordingly, the laser device may emit a homogeneous laser beam by adjusting a position at which a focus of the laser beam is formed. The laser device can effectively crystallize amorphous silicon.

For example, as shown in (a) of FIG. 13 , in the prior art, when a laser beam is defocused, the homogeneity in the short axis direction of the laser beam is deteriorated. On the other hand, as shown in (b) of FIG. 13 , in the laser device according to embodiments of the present invention, even when the laser beam is defocused, homogeneity in the short axis direction of the laser beam can be secured.

In the foregoing, although the description has been made with reference to exemplary embodiments of the present invention, those of ordinary skill in the art will present the present invention within the scope not departing from the spirit and scope of the present invention as set forth in the claims below. It will be understood that various modifications and variations are possible.

The present invention can be applied to laser devices and the like. For example, the laser device may be used to manufacture a smart phone, a tablet, a notebook computer, and a monitor using a laser beam.

Although the above has been described with reference to exemplary embodiments of the present invention, those of ordinary skill in the art may vary the present invention within the scope without departing from the spirit and scope of the present invention as set forth in the claims below. It will be understood that modifications and changes can be made to

100: laser generator 200: beam quality factor conversion unit
210: first sidewall 220: second sidewall
210a: first mirror 220: second mirror
300: telescope lens unit 310: first lens array
320: second lens array 330: third lens array
340: fourth lens array 400: homogenizer
410: first homogenizing lens 420: second homogenizing lens
430: condenser lens 500: condenser lens
600: stage LB: laser beam
LB1, LB2, LB3, LB4: first to fourth laser beams

Claims (20)

a laser generator for emitting a laser beam;
The laser beam emitted from the laser generator is divided in a first direction intersecting the emission direction to form a plurality of engraving beams, and the plurality of engraving beams are divided into the emission direction and a second direction intersecting the first direction a beam quality factor converting unit that is arranged and emitted;
The size of the laser beam emitted from the beam quality factor converting unit in the first direction is adjusted, the first lens array including first to n-th incident lenses and the aberration are different from the first lens array, a telescope lens unit including a second lens array including 1 to m th output lenses (where m and n are natural numbers greater than or equal to 1); and
and a condensing lens condensing the laser beam emitted from the telescope lens unit in the first direction. According to claim 1,
The first to nth incident lenses have the same curvatures as each other. 3. The method of claim 2,
The laser device, characterized in that the curvature of at least one of the first to m-th output lenses is different from the curvatures of the other output lenses except for the at least one output lens. According to claim 1,
The first to mth emitting lenses have the same curvatures as each other. 5. The method of claim 4,
The laser device according to claim 1, wherein a curvature of at least one incident lens among the first to nth incident lenses is different from curvatures of the other incident lenses except for the at least one incident lens. According to claim 1,
The first to nth incident lenses have the same thickness as each other. 7. The method of claim 6,
The laser device, characterized in that the thickness of at least one of the first to m-th output lenses is different from the thickness of the other output lenses except for the at least one output lens. According to claim 1,
The first to mth emitting lenses have the same thickness as each other. 9. The method of claim 8,
A thickness of at least one incident lens among the first to nth incident lenses is different from thicknesses of the other incident lenses except for the at least one incident lens. According to claim 1,
The laser beam focused by the condensing lens is irradiated on the stage,
The laser device, characterized in that the condensing lens is movable in a direction in which the laser beam is irradiated to the stage. According to claim 1,
The laser device according to claim 1, further comprising a homogenizing unit for homogenizing the laser beam emitted from the telescope lens unit in the second direction. According to claim 1,
The beam quality factor converter converts the size of the laser beam in the first direction and the size in the second direction to emit the laser beam. 13. The method of claim 12,
The beam quality factor converting unit changes the beam quality factor in the first direction and the beam quality factor in the second direction of the laser beam. According to claim 1,
The laser device according to claim 1, further comprising: a beam splitter for splitting the laser beam emitted from the beam quality factor converting unit and emitting it to the telescope lens unit. According to claim 1,
The laser device further comprising a beam mirror that reflects the laser beam emitted from the beam quality factor conversion unit and output to the telescope lens unit. a laser generator for emitting a laser beam;
The laser beam emitted from the laser generator is divided in a first direction intersecting the emission direction to form a plurality of engraving beams, and the plurality of engraving beams are divided into the emission direction and a second direction intersecting the first direction a beam quality factor converting unit that is arranged and emitted;
The size of the laser beam emitted from the beam quality factor converter in the first direction is adjusted, and the first to kth incident lenses and the first to kth incident lenses have the same curvatures and same thicknesses as the first to kth incident lenses. a telescope lens unit including first to kth output lenses (where k is a natural number equal to or greater than 2); and
and a condensing lens condensing the laser beam emitted from the telescope lens unit in the first direction. 17. The method of claim 16,
The first to kth incident lenses and the first to kth exit lenses are disposed to face each other,
At least one distance among distances by which the first to kth incident lenses and each of the first to kth exit lenses are spaced apart from each other is different from other distances except for the at least one distance. 17. The method of claim 16,
The laser beam focused by the condensing lens is irradiated on the stage,
The laser device, characterized in that the condensing lens is movable in a direction in which the laser beam is irradiated to the stage. 17. The method of claim 16,
The laser device according to claim 1, further comprising a homogenizing unit for homogenizing the laser beam emitted from the telescope lens unit in the second direction. 17. The method of claim 16,
The beam quality factor converting unit changes the beam quality factor in the first direction and the beam quality factor in the second direction of the laser beam, and determines the size of the laser beam in the first direction and the size in the second direction. A laser device, characterized in that it is converted and emitted.

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