JP2007290304A - Dividing method of brittle sheet material and its device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To smoothly divide a transparent thin brittle sheet accurately along separation lines without damage by a small number of processes without substantially applying mechanical stress. <P>SOLUTION: A joining body 4 of a mother glass substrate is divided along widthwise separation lines 501a-501d, lengthwise separation lines 502a-502f and diagonal separation lines 503a-503f by irradiating a short-wavelength laser beam having a wavelength equal to or lower than an ultraviolet-ray region. Position data of the joining body 4 placed on a specified position of an adsorption table is obtained by photographing alignment marks 402 by a CCD camera. Compensation is performed based on the position data so that the laser beam is irradiated accurately along the separation lines 501a-501d, 502a-502f and 503a-503f having set driving data of a laser irradiation head. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for dividing a brittle sheet material such as a glass plate with a laser beam and an apparatus for carrying out the method.

  Usually, in the manufacturing process of a liquid crystal display panel, a mother glass substrate is set between liquid crystal cells in order to separate a plurality of liquid crystal cells built in a joined body of a large area of a mother glass substrate into individual cells. Divide along the separation line.

As a method for dividing the mother glass substrate, conventionally, after a scribe line is scribed on one mother glass substrate using a cutter or a cutter wheel, the other mother glass substrate side (back side) is struck to each liquid crystal cell. A mechanical method of breaking (see Patent Document 1) is often used.
Japanese Patent Laid-Open No. 6-48755

  However, in the case of the mechanical mother glass substrate cutting method described above, a large stress is applied to the mother glass substrate of the workpiece (work), and the glass substrate is damaged during processing or the strength of the liquid crystal cell is reduced. There is. In addition, since scribe and break are repeated for each substrate, the number of manufacturing steps increases accordingly.

  An object of the present invention is to provide a brittle sheet material dividing method and apparatus capable of smoothly dividing a brittle sheet material without damaging it accurately along a separation line with few man-hours without substantially applying mechanical stress. It is.

  The brittle sheet material dividing method of the present invention is a method of dividing a substantially transparent brittle sheet material along a preset separation line, and a laser beam having a wavelength of an ultraviolet region or less is applied to the brittle sheet plate. Irradiation is performed on the surface along the separation line.

  The brittle sheet material cutting device of the present invention is a device that cuts a substantially transparent brittle sheet material along a preset separation line, and emits laser light having a wavelength equal to or less than the ultraviolet region. A light emitting element, an XY movement mechanism for moving the laser light emitting element and the brittle sheet material relative to each other in the X and Y directions perpendicular to each other in a plane parallel to the surface of the brittle sheet material; And a laser beam scanning mechanism that freely scans the direction in an arbitrary direction in the plane.

  According to the brittle sheet material cutting method of the present invention, the laser beam having a wavelength equal to or less than the ultraviolet region is irradiated onto the brittle sheet material of the workpiece, so that the energy of the laser beam is efficient even though the workpiece is a transparent brittle sheet material. It is well absorbed and can be cut accurately and smoothly without damage along a predetermined separation line.

  Further, according to the brittle sheet material cutting device of the present invention, the laser light emitting element that emits laser light having a wavelength equal to or shorter than the ultraviolet region and the brittle sheet material are orthogonal to each other in a plane parallel to the surface of the brittle sheet material. Since it has an XY movement mechanism that moves relative to each other in the direction and a laser beam scanning mechanism that freely scans the irradiation direction of the laser beam in any direction within the plane, a transparent thin brittle sheet material is used. Even if it exists, it can cut | disconnect efficiently in a short time freely along a desired separation line.

  In the brittle sheet material cutting method of the present invention, the laser beam irradiation position and the brittle sheet material are moved relative to each other in two directions orthogonal to each other in a plane parallel to the surface of the brittle sheet material, and the laser beam irradiation direction Is preferably scanned freely in an arbitrary direction in the plane, whereby the brittle sheet material can be smoothly cut into a desired shape other than a rectangle.

  Further, the brittle sheet material dividing method of the present invention is effectively applied when dividing one of a pair of mother glass substrates bonded to form a plurality of liquid crystal cells. A liquid crystal cell having an accurate outer shape can be efficiently manufactured with a small number of man-hours.

  FIG. 1 is a plan view showing a mother glass substrate assembly before being divided into individual liquid crystal cells by a glass substrate cutting apparatus as one embodiment of the present invention, and FIGS. 2 and 3 are one embodiment of the present invention. It is the elevation which shows a glass substrate cutting device, and a top view.

  In FIG. 1, mother glass substrates 1 and 2 are joined via a frame-shaped sealing material 3. Six identical liquid crystal cells are collected from the mother glass substrate assembly 4, and therefore, for each of the cell collection areas 401 a to 401 f (indicated by alternate long and short dash lines) that are partitioned into 6 equal sections of 2 rows × 3 columns, A rectangular frame-shaped sealing material 3 is disposed. In addition, alignment marks 402 are respectively provided at a pair of diagonal corner portions of each of the mother glass substrates 1 and 2. These alignment marks 402 and 402 serve as a reference indicating the positions of the individual mother glass substrates 1 and 2 and the bonded mother glass substrate assembly 4 after bonding.

  For the mother glass joined body 4, a separation line that defines the outer shape of a substantially rectangular liquid crystal cell is set. As shown by a two-dot chain line, the separation line defines four lateral separation lines 501a to 501d that define the short sides of the outer shape of each liquid crystal cell and the long sides of the outer shape of each liquid crystal cell that are orthogonal to these. 6 vertical separation lines 502a to 502f and oblique separation lines 503a to 503f for removing one corner portion of each liquid crystal cell.

Next, the glass substrate cutting apparatus of this embodiment is demonstrated based on FIGS.
2 and 3, the base 6 is provided with an X-axis (perpendicular to paper surface) moving mechanism 7 by a linear servo motor. The X-axis moving mechanism 7 includes a slider 701 that freely slides on the surface of the base 6 in the X-axis direction, and a stator portion 702 that is installed inside the base 6. In the stator portion 702, a plurality of permanent magnets (not shown) are arranged in parallel along the X-axis direction with the individual N poles and S poles alternately adjacent to each other. The driving means of the X-axis moving mechanism 7 is not limited to the linear servo motor system, and a ball screw driving system using a pulse motor, a timing belt driving system, and the like are also preferably used.

  On the slider 701 of the X-axis moving mechanism 7, the suction stage 8 is installed. The suction stage 8 holds the workpiece by vacuum suction. In the present embodiment, the mother glass substrate assembly 4 in which the plurality of liquid crystal cells shown in FIG. 1 are built as a workpiece is accurately positioned and held at a predetermined position of the suction stage 8.

  Support blocks 9a and 9b are installed on both sides of the moving path of the slider 701 extending in the X-axis direction on the surface of the base 6, respectively. On the upper surfaces of the support blocks 9a and 9b, guide rails 11a and 11b are respectively installed extending in the X-axis direction. Carriages 12a and 12b are slidably installed on the guide rails 11a and 11b.

  A head main drive unit 14 for driving the laser irradiation head 13 is provided between the pair of carriages 12a and 12b. The head main drive unit 14 includes a servo motor 141 and a ball screw 142, and the laser irradiation head 13 is installed on the ball screw 142 via a nut (not shown). Accordingly, the laser irradiation head 13 is freely reciprocated in the Y-axis direction perpendicular to the extending direction of the ball screw 142, that is, the X-axis direction, by the servo mechanism including the servo motor 141, the ball screw 142, and the nut.

  Further, the head sub-driving unit 15 is installed on one support block 9a. The head auxiliary drive unit 15 also includes a servo motor 151 and a ball screw 152, and a carriage 12a is installed on the ball screw 152 via a nut (not shown). Thus, the head main drive unit 13, the laser irradiation head 13, and the pair of carriages 12a and 12b are integrally formed in the X-axis direction in which the ball screw 152 extends by a servo mechanism including a servo motor 151, a ball screw 152, and a nut. It can be freely reciprocated.

  As shown in FIG. 4, the laser irradiation head 13 of the present embodiment is generally composed of a laser oscillator 131, a universal scan mirror 132, and an fθ lens 133. The laser oscillator 131 includes a laser light emitting element that emits a laser beam having a wavelength equal to or less than the ultraviolet region. In this embodiment, an excimer laser light emitting element having a wavelength of 126 to 351 nm is used. The free scan mirror 132 freely changes the scanning direction of the laser beam emitted from the laser oscillator 131 not only in the X and Y axis directions on the work surface, that is, the surface of the mother glass substrate assembly 4, but also in other 360-degree orientations. It is a scan mirror that can. The fθ lens 133 is provided to allow the laser beam reflected by the free scan mirror 132 to enter perpendicularly with a focus on the surface of the mother glass substrate assembly 4.

  Returning to FIG. 2, an image recognition CCD camera 16 is installed above the base 6, and this CCD camera 16 is connected to an image processing unit 17. As shown in FIG. 3, the CCD camera 16 images the alignment mark 402 (see FIG. 1) of the mother glass substrate assembly 4 sucked and held on the suction table 8, and the data is sent to the image processing unit 17. send. The image recognition CCD camera 16 has a pair of alignment marks 402 provided at diagonal corners of the mother glass substrate assembly 4 in order to detect the set position of the mother glass substrate assembly 4 more accurately. A total of two units may be installed one by one in correspondence with 402.

  Then, the X-axis moving mechanism 7 of the suction table 8 and the servo motors 141 and 151 of the driving source for moving the laser irradiation head 13 in the X and Y axis directions, the laser irradiation head 13 main body, and the CCD camera 16 are connected. The image processing unit 17 is connected to a controller 18 that controls the entire glass substrate cutting apparatus.

  Next, the cutting procedure of the mother glass substrate assembly 4 by the glass substrate cutting apparatus of the present embodiment configured as described above and the operation accompanying it will be described.

  First, as shown in FIG. 3, the mother glass substrate assembly 4 is set at a predetermined position on the suction table 8. When the setting of the mother glass substrate assembly 4 is completed, the alignment mark 402 is imaged by the CCD camera 16, and this imaging data is sent to the image processing unit 17. The image processing unit 17 calculates accurate position data of the mother glass substrate assembly 4 based on the imaging data, and outputs it to the controller 18.

  The controller 18 recognizes the position of the mother glass substrate assembly 4 with high accuracy based on the position data sent from the image processing unit 17, and the amount of deviation in the X and Y axis directions with respect to preset reference position data. Δx, Δy and an inclination amount Δθ with respect to the axial directions are calculated. Then, preset X and Y axis direction drive data is corrected based on the calculated deviation amounts Δx and Δy, and the slider 7 and the laser irradiation head 13 are corrected based on the corrected X and Y axis direction drive data. Either one or both are moved, and the laser irradiation head 13 is put on standby at an appropriate laser irradiation start position.

  In the present embodiment, laser light is irradiated to each of the partial cell sections 4011a, 4012a to 4011f, and 4012f obtained by equally dividing the liquid crystal cell collection areas 401a to 401f shown in FIG. These partial cell sections 4011a, 4012a to 4011f, and 4012f are sections that fall within the scanning range of the laser irradiation head 13.

  Therefore, if, for example, the partial cell section 4011a is first irradiated with laser, the laser irradiation head 13 is put on standby at the irradiation start position above the partial cell section 4011a. Next, a drive signal is sent to the laser irradiation head 13, the laser oscillator 131 is turned on to emit laser light, and the free scan mirror 132 is driven to scan the laser light. In this laser beam scanning, preset scan data is corrected in consideration of the already calculated misalignment data Δx, Δy, and Δθ of the mother glass substrate assembly 4, and the corrected scan data is added to the corrected scan data. To be implemented. Thereby, the laser beam emitted from the laser irradiation head 13 is accurately irradiated along the preset separation lines 502a, 501b, and 502b.

  Here, since the laser light applied to the mother glass substrate 1 toward the front surface of the mother glass substrate assembly 4 is an excimer laser having a wavelength of 126 to 351 nm which is equal to or less than the ultraviolet region, the mother glass substrate 1 is substantially formed. Even if it is transparent, most of the irradiated laser light is not transmitted, but the energy is efficiently absorbed and heat is generated, and the irradiated portion is melted and evaporated. As a result, a slit is accurately drilled in the mother glass substrate 1 in the partial cell section 4011a along the separation lines 502a, 501b, and 502b.

  In this embodiment, since an excimer laser having a wavelength equal to or less than the ultraviolet region is used, a light absorber for efficiently absorbing laser light energy conventionally used when cutting the transparent plate is provided along the separation line. However, by using a light absorber in combination, the laser light irradiation time can be shortened, and the number of manufacturing steps of the liquid crystal display panel can be reduced.

  When the irradiation of the laser beam to the inside of the partial cell section 4011a is completed, similarly, either or both of the slider 7 and the laser irradiation head 13 are moved in the X and Y axis directions, and the part which is the next laser beam irradiation target section The laser irradiation head 13 is put on standby at a laser irradiation start position for the cell section 4012a. Then, as in the case of the partial cell section 4011a, the laser beam irradiation is started and the laser beam is scanned based on the corrected scan data. Thereby, the emitted laser light is accurately irradiated along the separation lines 502b, 503a, 501a, and 502a. An oblique separation line 503a exists in the partial cell section 4012a. However, the laser beam can be accurately scanned along the oblique separation line 503a by the universal scanning mirror 142.

  When irradiation of laser light to one cell collection area 401a composed of adjacent partial cell sections 4011a and 4012a is completed, the same laser as the operation performed on the cell collection area 401a described above is performed on the adjacent cell collection area 401b, for example. Repeat the light irradiation operation. Then, by sequentially performing the same laser light irradiation operation on the adjacent cell collection areas 401c, 401d, 401e, and 401f, the laser light irradiation process for the mother glass substrate 1 positioned on the front side is completed. At this stage, one mother glass substrate 1 is provided with slits along the horizontal separation lines 501a to 501d, the vertical separation lines 502a to 502f, and the diagonal separation lines 503a to 503f. Since 2 is not divided, it is not separated into individual liquid crystal cells.

  Next, the mother glass substrate assembly 4 is turned over, and the same laser light irradiation process as that performed on the mother glass substrate 1 is performed on the mother glass substrate 2 facing front. At the stage where the laser beam irradiation process for the other mother glass substrate 2 is completed, the mother glass substrate assembly 4 is divided into six liquid crystal cells.

  As described above, according to the glass substrate cutting method of the present embodiment and the apparatus for performing the method, the workpiece is transparent for a liquid crystal display panel because the laser beam having a wavelength of ultraviolet region or less is irradiated onto the glass substrate of the workpiece. Even with a thin glass substrate, the energy of the laser beam is efficiently absorbed and can be cut accurately and smoothly without being damaged along a predetermined separation line.

  Further, the laser irradiation head 13 is moved 360 by the free scanning mirror 132 while moving either one or both of the slider 7 and the laser irradiation head 13 on which the mother glass substrate assembly 4 as a workpiece is set in the X and Y axis directions. Since the laser beam can be irradiated in all directions, the degree of freedom of the external shape of the liquid crystal cell obtained by dividing the mother glass substrate assembly 4 is greatly increased, and the mechanism of the cutting device itself This simplifies the maintenance durability.

  Furthermore, the CCD camera 16 accurately recognizes the set position of the mother glass substrate assembly 4 as a workpiece, and the controller corrects the preset X and Y axis direction drive data and head scan data based on the position recognition data. Since the laser beam irradiation is performed, the mother glass substrate can be divided with high accuracy and the operation time can be shortened.

  The present invention is not limited to the above embodiment. For example, the thin and brittle sheet plate as a workpiece is not limited to a mother glass substrate for a liquid crystal display panel, but a thin glass plate used for other than a liquid crystal display panel, or The present invention is also effectively applied to a ceramic plate other than a glass plate.

  Further, the suction table on which the work is placed may be a turntable. In that case, as a scanning mirror of the laser irradiation head, a two-axis scanning mirror formed by combining two mirrors that can rotate in directions orthogonal to each other. Can be used.

It is a top view which shows the mother glass substrate conjugate | zygote processed by the glass plate parting apparatus as one Embodiment of this invention. It is the elevation which showed the said glass plate parting apparatus. It is the top view which showed the said glass plate parting apparatus. It is explanatory drawing which showed the structure of the laser irradiation head in the said glass plate parting apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 Mother glass substrate 3 Frame-shaped sealing material 4 Mother glass substrate conjugate | zygote 401a-401f Cell collection area 4011a, 4012a
˜4011f, 4012f Partial cell section 5 Separation line 501a-501d Horizontal separation line 502a-502f Vertical separation line 6 Base 7 Slider 8 Suction stage 9a, 9b Support block 11a, 11b Guide rail 12a, 12b Carriage 13 Laser irradiation head 131 Laser Oscillator 132 Swivel scan mirror 133 fθ lens 14 Head main drive unit 15 Head sub drive unit 16 CCD camera 17 Image processing unit 18 Controller

Claims (4)

A method of dividing a substantially transparent brittle sheet material along a preset separation line,
A method for dividing a brittle sheet material, which comprises irradiating the surface of the brittle sheet plate with laser light having a wavelength of an ultraviolet region or less along the separation line.   The irradiation position of the laser beam and the brittle sheet material are moved relative to each other in two directions orthogonal to each other in a plane parallel to the surface of the brittle sheet material, and the irradiation direction of the laser beam is arbitrary in the plane. The brittle sheet material cutting method according to claim 1, wherein scanning is performed freely in a direction.   The glass sheet cutting method according to claim 1 or 2, wherein the brittle sheet material is one of a pair of mother glass substrates bonded to form a plurality of liquid crystal cells. An apparatus for cutting a substantially transparent brittle sheet material along a preset separation line,
A laser light emitting element that emits laser light having a wavelength less than or equal to the ultraviolet region; and
An XY movement mechanism for moving the laser light emitting element and the brittle sheet material relative to each other in the X and Y directions orthogonal to each other in a plane parallel to the surface of the brittle sheet material;
A brittle sheet material cutting device, comprising: a laser beam scanning mechanism that freely scans an irradiation direction of the laser beam in an arbitrary direction within the plane.

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