KR20030088519A - Pattern forming apparatus for light guide panel - Google Patents

Abstract

PURPOSE: A device for forming patterns for a light guide plate is provided to form light guide pattern units on a large light guide plate by mechanically moving at least one mirror header unit, and reduce a processing time by increasing moving speed of a header moving unit. CONSTITUTION: A pattern designing system(71) has data related to patterns to be formed on a light guide plate(21). A control system(72) is connected with the pattern designing system for transmitting a position signal consistent with coordinates of each pattern. A header moving unit(74) mechanically moves in all directions according to the position signal received from the control system. A laser system(73) outputs laser beams by the movement of the header moving unit and synchronized pulse signals. A lens part(75) makes the laser beams focused on a scanning surface(21a) of the light guide plate via the header moving unit. A vacuum unit(410) is installed to prevent the light guide plate from getting bent due to local heating of the laser beams. A blowing unit(600) is installed to remove smoke generated while a plurality of light guide pattern units(25) on the light guide plate.

Description

Pattern forming apparatus for light guide plate {Pattern forming apparatus for light guide panel}

The present invention relates to a light guide plate, and more particularly, to a light guide plate pattern forming apparatus capable of forming a light guide pattern portion by scanning a laser by using a header moving part which is movable up, down, left and right on the light guide plate.

In general, a light guide panel is a plate that provides a path for uniformly scattering and diffusing light scanned from a light source, and is used for a light receiving type flat panel display device such as a liquid crystal display device or a surface light source device used for an illumination signboard. Included.

As the surface light source device, a cold cathode fluorescent lamp (CCFL) or a method of disposing a LED and a flat fluorescent lamp method in which a phosphor-coated substrate is assembled are widely used. Cold cathode fluorescent lamps can be classified into an edge light method using a light guide plate and a direct light method overlapping on a plane according to the arrangement of the light source on the display surface.

FIG. 1 is a diagram illustrating a conventional surface light source device 10.

Referring to the drawings, the surface light source device 10 includes a light guide plate 11, a reflection plate 12 disposed below the light guide plate 11, and at least one light source 13 installed on a sidewall of the light guide plate 11. It includes a cover member 14 surrounding the light source (13). A diffusion plate, a prism sheet, or the like may be further installed on the light guide plate 11, and a cold cathode fluorescent lamp or an LED may be used as the light source 13.

In the surface light source device 10 having the structure as described above, the light scanned from the light source 13 is incident on the light guide plate 11, and the light guided to the light guide plate 11 is formed at each part by the reflecting plate 12. Reflected upwards with relatively uniform illuminance, this light diffuses forward through a diffuser plate or prism sheet.

At this time, the light guide pattern portion 15 is formed on the bottom surface of the light guide plate 11 so as to scatter and diffuse incident light. The light guide pattern portion 15 is a plurality of dot patterns formed by using a bead-shaped titanium oxide (TiO ₂ ) and an ink containing a glass or acrylic material. The light guide pattern portion 15 may be formed by printing by dropping ink on a mask having a corresponding pattern.

By the way, the light guide pattern part 15 formed by the printing method is complicated by a series of manufacturing processes, such as the preparation of the strap and plate making of the mask, the ink, and the printing of the light guide plate. For this reason, many defects, such as a fall of a dot pattern at the time of printing, a nonuniformity of mask discharge, and a dirt of a printing surface, arise. In addition, the light guide plate 11, which is not properly printed, is not reproducible and disadvantageous in terms of manufacturing cost.

In order to improve this point, the light guide pattern part was conventionally formed by the laser processing method. A laser processing method is a method of forming a light guide pattern portion by scanning a laser beam on a light guide plate using a laser device. This method can prevent the dot pattern from falling off or the unevenness of the printing surface when forming the light guide pattern portion by the printing method described above, and can overcome the difficulty of forming a fine pattern.

However, when the light guide pattern portion is formed using a laser device, the following problems may occur.

First, bending of the light guide plate may occur because strong energy is introduced into one surface of the light guide plate. Due to this warpage phenomenon, the productivity is significantly lowered as the yield is lowered.

Second, the laser beam may be scattered or absorbed by the smoke generated while a part of the light guide plate is removed by thermal energy. Accordingly, the quality of the light guide pattern portion formed on the light guide plate cannot be guaranteed.

Third, by using a laser scanner having an optical condensing means, the price of equipment increases.

The present invention is to solve the problems as described above, by forming a light guide pattern portion on the light guide plate by a laser system that can be moved freely up, down, left and right by mechanical driving, and the interference element generated during the scanning of the laser beam in advance It is an object of the present invention to provide a pattern forming apparatus for a light guide plate having a structure and a method thereof which can be blocked.

1 is a cross-sectional view schematically showing a conventional surface light source device;

Figure 2 is an exploded perspective view showing a surface light source device according to an embodiment of the present invention,

3 is a cross-sectional view taken along the line II of FIG. 2;

4 is a configuration diagram schematically showing a state in which a light guide pattern portion is formed on a light guide plate according to a first embodiment of the present invention;

5 is a configuration diagram schematically showing a state in which a light guide pattern portion is formed on a light guide plate according to a second embodiment of the present invention;

6 is a configuration diagram schematically illustrating a state in which a light guide pattern portion is formed on a light guide plate according to a third embodiment of the present invention;

7 is a schematic view showing a system for forming a light guide pattern portion on a light guide plate according to an embodiment of the present invention;

8 is a configuration diagram schematically showing a header moving unit according to an embodiment of the present invention.

<Brief description of symbols for the main parts of the drawings>

21 ... Light guide plate 41 ... Plate

70 ... Light guide pattern forming system 71 ... Pattern design system

72 Control system 73 Laser system

74.Header moving part 75.Lens part

76 ... XY moving part 77 ... mirror header part

410. Vacuum 500. Heating

600 Blower 610 Exhaust

In order to achieve the above object, the light guide plate pattern forming apparatus according to the aspect of the present invention,

A light guide plate pattern forming apparatus for forming a plurality of patterned light guide pattern portions on a light guide plate,

A pattern design system in which data on a pattern to be formed on the light guide plate is input;

A control system connected to the pattern design system and transmitting a position signal corresponding to a coordinate value of each pattern to be formed on the light guide plate;

A header moving unit which moves up, down, left and right mechanically according to the position signal received from the control system;

A laser system for outputting a laser beam according to a pulse signal synchronized with movement of the header moving unit;

A lens unit for allowing the laser beam output from the laser system to focus on the scanning surface of the light guide plate via the header moving unit;

Bending prevention means provided to prevent the light guide plate from being bent by local heating of the laser beam; And

And absorption scattering preventing means installed to remove smoke generated while the light guide pattern portion is formed on the light guide plate.

The header moving part may include an XY moving part mechanically movable in the XY direction, and at least one mirror header part coupled to the XY moving part to reflect the laser beam scanned from the laser system to the light guide plate. do.

In addition, the XY moving unit includes a horizontal guide rail provided with the mirror header unit, a horizontal linear motor for supplying power for horizontal reciprocating movement of the mirror header unit with respect to the horizontal guide rail, and a direction perpendicular to the horizontal guide rail. And a vertical linear motor for supplying power for vertically reciprocating the horizontal guide rail with respect to the vertical guide rail to be installed.

Further, the mirror header portion reflects the first mirror header portion fixed to the horizontal guide rail corresponding to the beam path axis of the laser system, the laser beam reflected from the first mirror header portion onto the light guide plate, and the horizontal guide rail. It characterized in that it comprises a second mirror header portion coupled to the horizontal movement.

In addition, the bending preventing means is characterized in that it comprises a plate on which the light guide plate is mounted, and a vacuum unit for providing a vacuum force for vacuum suction the light guide plate to the plate by forming a vacuum passage in the plate.

Further, the absorption scattering prevention means is installed on one side of the light guide plate, characterized in that it comprises a blower which is installed to cool the light guide plate at the same time to blow the smoke by supplying a gas of more than atmospheric pressure to the scanning surface of the light guide plate through a blower pipe do.

Hereinafter, a light guide plate pattern forming apparatus according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 2 illustrates a surface light source device 20 according to an embodiment of the present invention, and FIG. 3 is taken along the line II of FIG. 2.

2 and 3, the light guide plate 21 is provided in the surface light source device 20. The light guide pattern portion 25 is formed on the bottom surface of the light guide plate 21. The light guide pattern portion 25 is preferably a dot, a straight line, or a groove of a mixed type in which a dot and a straight line are combined. Alternatively, the shape may be quadrangular, lattice, or a combination of quadrangle and lattice. The light guide pattern portion 25 is asymmetrical to effectively scatter and diffuse incident light, and may change the pattern size in the entire region of the light guide plate 21 according to the amount of light.

The lower portion of the light guide plate 21 is provided with a reflecting plate 22 for reflecting the incident light upward. At least one light source 23 for scanning light with the light guide plate 21 is provided on the sidewall of the light guide plate 22. As the light source 23, a cold cathode fluorescent lamp or an LED is preferable. The cover member 24 is installed outside the light source 23. On the other hand, the light guide plate 21 is further provided with a diffusion plate 26 for scattering and diffusing light. In addition, the light diffusion part made of fine scratches may be further formed on the upper surface of the light guide plate 21 so that the light scanned from the light source 23 can be uniformly diffused forward.

In the surface light source device 20 having the above structure, each pattern of the light guide pattern portion 25 formed on one surface of the light guide plate 21 may be formed by scanning a laser beam using a laser system. At this time, the processable obstacles generated by heat or smoke generated during the scanning of the laser beam can be removed by means of an interference prevention means provided separately.

4 illustrates a state in which the light guide pattern portion 25 is formed in the light guide plate 21 according to the first embodiment of the present invention.

Referring to the drawing, the light guide plate 21 is mounted on the plate 41. The surface 21a on which the light guide pattern part 25 is to be formed on the light guide plate 21 is positioned to face the laser header moving part 400 in which the laser beam is scanned. The header moving unit 400 may move a laser beam on the light guide plate 21 like an arrow indicated by a solid line and a dotted line while moving up, down, left, and right of the light guide plate 21 by mechanical driving by an XY stage. The configuration of the laser system including the header moving unit 400 will be described later.

When the laser beam having a wavelength of 1 micrometer or more is scanned from the header moving part 400 on the scanning surface 21a of the light guide plate 21, the scanning surface 21a has a focus portion of the laser beam and a peripheral portion thereof. As the temperature rises, grooves having a substantially U-shaped or V-shaped cross-sectional shape can be formed. Such grooves are formed in the entire region of the light guide plate 21 to form the light guide pattern portion 25.

Here, when the laser beam is locally scanned on a part of the scanning surface 21a of the light guide plate 21, a heating reaction is gradually enlarged over the width of the laser beam on the scanning surface 21a, and this heating reaction is intensified. In this case, deformation of the light guide plate 21 such as warpage occurs. The warpage phenomenon is severely generated at the periphery of the light guide plate 21. As a result, the angle of incidence of the laser beam is changed, making it difficult to form an elaborate pattern. In order to prevent this, the light guide plate 21 is provided with a bending preventing means.

That is, the plate 41 on which the light guide plate 21 is mounted is provided with a vacuum unit 410 so as to completely adsorb one surface of the light guide plate 21 opposite to the region where the light guide pattern portion 25 is formed. .

The vacuum unit 410 is provided with a plurality of vacuum passages 411 so as to be able to vacuum-adsorb the light guide plate 21 through the inside of the plate 41. The vacuum unit 410 is a pump system such as a mechanical vacuum pump, a momentum transfer vacuum pump, or an inflow vacuum pump, and the front of the light guide plate 21 through the vacuum passage part 411 by the pumping force of the pump. It can be said that it is possible to vacuum suction. In this case, a vacuum pad 412 may be further installed at the portion where the light guide plate 21 is adsorbed in order to prevent scratches caused by external force during the adsorption. As an alternative to the vacuum system described above, the light guide plate 21 may be fixed by employing a physical mechanism such as a joint fixing or a clamp fixing.

In this way, the light guide pattern portion 25 may be formed by scanning the laser beam while the light guide plate 21 is fixed by the bending preventing means. Accordingly, the warpage phenomenon due to the local heating of the laser beam may be prevented in advance.

5 illustrates a state in which the light guide pattern portion 25 is formed in the light guide plate 21 according to the second embodiment of the present invention.

Here, the same reference numerals as in the above-described drawings indicate the same members having the same function.

Referring to the drawing, the light guide plate 21 is mounted on the plate 21. The scanning surface 21a of the light guide plate 21 is disposed to face the laser header moving part 400 in which the laser beam is scanned. In the plate 21, a vacuum passage part 411 is formed to suck the light guide plate 21 in a vacuum, and the vacuum passage part 411 is a vacuum part 410 such as a vacuum pump system that provides a vacuum force. ) On the path of the vacuum passage part 411, a vacuum pad 412 is provided to prevent scratches on the surface of the light guide plate 21 that are adsorbed upon vacuum absorption.

At this time, additional bending prevention is prevented in case the adhesion of the plate 41 to the light guide plate 21 is insufficient when the laser beam output from the laser system is scanned while maintaining the horizontal level of the light guide plate 21 by the vacuum system. Means can be installed.

That is, the heating part 500 is provided in the plate 41. The heating unit 500 is provided with a heating wire 511 which is installed in the plate 41 and can generate heat electrically. Alternatively, heat may be generated by ultrasonic waves to heat the plate 41 and transfer the heat to the light guide plate 21.

As such, when a predetermined heat is heated on the plate 41, the heat heated from the plate 41 is increased by a temperature that is increased due to the laser beam scanned on the scanning surface 21a of the light guide plate 41. It is transmitted to the opposite side of the pattern forming portion 25 of 41. Accordingly, the light guide plate 21 can eliminate the temperature deviation of the upper and lower portions, it is possible to prevent the warping phenomenon in advance.

On the other hand, since the etching method by scanning the laser beam on the light guide plate 21 is a method of heating the surface of the light guide plate 21 made of acrylic resin with strong energy, smoke is generated by the acrylic resin material to be evaporated. Such smoke may cause absorption or scattering of the laser beam during the scanning process of forming the light guide pattern portion 25 on the light guide plate 21. As a result, the energy of the laser beam scanned by the light guide plate 21 is reduced, thereby interrupting the processing of the light guide pattern portion 25 having a desired pattern.

FIG. 6 illustrates a state in which the light guide pattern portion 25 is formed in the light guide plate 21 according to the third embodiment of the present invention.

Referring to the drawings, the light guide plate 21 is seated on the plate 41, is connected to the plate 41 through the vacuum passage 411, the vacuum pump for supplying a vacuum force to the light guide plate 21 A vacuum section 410 such as a system is installed. A vacuum pad 412 is provided on the suction surface of the light guide plate 21.

In this case, a portion of the light guide plate 21 is removed by thermal energy during scanning of the laser beam using the laser header moving unit 400 on the scanning surface 21a of the light guide plate 21 to generate smoke s. Smoke generated in this way can be removed by the absorption scattering prevention means.

That is, one side of the light guide plate 21 is provided with a blower 600 to remove the smoke generated. The blower 600 injects a gas having a normal pressure or higher to blow air into the scanning surface 21a of the light guide plate 21 through the blower tube 601. The blower 600 performs a role of cooling the upper surface of the light guide plate 21 while removing smoke from the light guide plate 21.

In addition, an exhaust unit 610 is installed at the other side of the light guide plate 21 to remove smoke blown by the blower 600. The exhaust unit 610 sucks and discharges smoke of an acrylic resin, which is an element of the light guide plate 21, which is evaporated from the scanning surface 21a of the light guide plate 21, thereby preventing absorption or scattering of the laser beam due to the smoke. can do.

FIG. 7 illustrates a system 70 for forming a light guide pattern portion on a light guide plate in one embodiment of the present invention.

Referring to the drawings, the pattern forming system 70 includes a pattern design system 71, a control system 72, a laser system 73, a header moving unit 74, a lens unit 75, and a light guide plate. And (31), warpage prevention means for preventing warpage and absorption scattering prevention means for preventing absorption or scattering of the laser beam.

The header moving part 74 reflects the XY moving part 76 which is mechanically movable in the XY direction, and the laser beam which is combined with the XY moving part 76 and scanned from the laser system 73 to the light guide plate 21. A plurality of mirror header portions 77 are provided.

The operation of the pattern forming system 70 having the above configuration is as follows.

The data input to the pattern design system 71 for the design rule of each pattern of the light guide pattern portion 25 to be formed on the light guide plate 21 causes the control system 71 to correspond to the coordinate values of each pattern. The position signal corresponding to the area to be scanned on the scanning surface 21a of 21 is transmitted to the header moving unit 74.

The pulse signal synchronized with the mechanical up, down, left, and right movement of the header mover 74 is transmitted to the laser system 73 through the control system 72, and a laser beam is output from the laser system 73.

The laser beam thus output is reflected from the plurality of mirror header portions 77 and scanned on the scanning surface 21a of the light guide plate 21 through the lens portion 75 to process the surface of the light guide plate 21. . Accordingly, a pattern forming part 25 such as a dot pattern is formed on the scanning surface 21a of the light guide plate 21.

In this case, the light guide plate 21 has a vacuum part connected to the plate 41 on which the light guide plate 21 is seated in order to prevent the warpage phenomenon caused by the local heating of the laser beam output from the laser system 73. The pump 410 is operated to provide a vacuum force through the vacuum passage 411. As a result, the light guide plate 21 is vacuum-absorbed with respect to the plate 41, so that the entire area is maintained at a horizontal level.

In addition, when the adhesion of the light guide plate 21 to the plate 41 is not sufficient even by the vacuum means, a predetermined power is applied from the heating part 500 connected to the plate 41 to provide the light guide plate 41. By eliminating the temperature difference between the upper and lower surfaces, warpage can be further prevented.

On the other hand, air of a predetermined pressure is blown to the scanning surface 21a from the blower 600 installed at one side of the light guide plate 21 in order to prevent interference with pattern processing due to the smoke generated from the light guide plate 21. Smoke removed by the blower 600 is sucked and discharged through an exhaust unit 610 provided on the other side of the light guide plate 21. As a result, absorption or scattering of the laser beam can be prevented.

8 illustrates a header moving unit 80 according to an embodiment of the present invention.

Referring to the drawings, as described above, the header moving part 80 reflects the XY moving part 81 which is mechanically movable in the XY direction and the laser beam output from the laser system 82 installed on one side to the light guide plate. A plurality of mirror header portion 83 coupled to the XY moving portion 81 is included.

The XY moving part 81 is provided with a horizontal guide rail 84 arranged in the X direction. The horizontal guide rail 84 is coupled to a mirror header portion 83 including first and second mirror header portions 83a and 83b. The first mirror header portion 83a is provided on a horizontal guide rail 84 that is coaxial with the laser system 82. The second mirror header portion 83b is coupled to be movable along the horizontal guide rail 84.

In addition, the horizontal guide rail 84 is provided with a horizontal linear motor 85 so that the second mirror header portion 83b can move horizontally along the horizontal guide rail 84. The horizontal linear motor 85 is a horizontal motion source connected to the second mirror header portion 83b. On the other hand, a condensing lens portion 86 is coupled to the second mirror header portion 83b, and the condensing lens portion 86 is horizontally movable with the second mirror header portion 83b.

A plurality of vertical guide rails 87 are provided at both ends of the horizontal guide rail 84. The vertical guide rail 87 is provided with at least one vertical linear motor 88. The horizontal guide rail 84 is capable of vertical movement along the vertical guide rail 87 in accordance with the power of the vertical linear motor 88.

As such, the at least one mirror header portion 83 is capable of horizontal movement along the horizontal guide rail 84 by the power of the horizontal linear motor 85, the horizontal guide rail 84 is a vertical linear motor ( It is possible to vertically move along the vertical guide rail 87 by the power of the 88.

In this case, the optical output signal transmitted to the laser system 82, the horizontal transfer signal transmitted to the horizontal linear motor 85, or the vertical transfer signal transmitted to the vertical linear motor 88 are controlled by the control system 89. Will be sent from

Looking at the operation of the header moving unit 90 having the above structure as follows.

The pulse signal synchronized with the moving speed of the second mirror header portion 83b mechanically transferred by the transfer signal of the control system 89 is transmitted to the laser system 82 through the control system 89, and the laser The laser beam is output from the system 82.

The laser beam thus output reaches the first mirror header portion 83a fixed to one side of the horizontal guide rail 84. The laser beam that reaches the first mirror header portion 83a is reflected at a right angle by the mirror to reach the second mirror header portion 83b. The laser beam that reaches the second mirror header portion 83b is reflected at right angles by the mirror to reach the scanning surface of the light guide plate through the condensing lens portion 86 to form the light guide pattern portion. In this case, as the second mirror header portion 83b is moved in the horizontal direction of the machining work area A by the horizontal linear motor 85, the laser beam is output in the horizontal direction of the light guide plate to form a light guide pattern. Let's do it.

On the other hand, since the vertical guide rails 87 are coupled to both ends of the horizontal guide rails 84, the vertical guide rails 84 are vertically driven by the power of the vertical linear motor 88 that receives the vertical transfer signal from the control system 89. Since the horizontal guide rail 84 is movable in the vertical direction along the guide rail 87, the laser beam can be output in the vertical direction of the light guide plate to form a light guide pattern.

As described above, the light guide plate pattern forming apparatus of the present invention can obtain the following effects.

First, since at least one mirror header portion is mechanically movable up, down, left, and right on the XY moving portion, the light guide pattern portion can be processed on a light guide plate of a large size.

Second, since the output of the laser system can be increased, the processing time can be shortened by increasing the moving speed of the header moving part.

Third, since the expensive laser scanner is not used, the equipment price for forming the pattern forming part of the light guide plate can be lowered.

Fourth, since the incident angle of the laser beam according to the position does not change, it is possible to prevent distortion of the light guide pattern portion.

Fifth, the light guide plate is prevented from being bent due to local heat generated when the laser beam is scanned onto the light guide plate.

Sixth, absorption and scattering may occur due to the smoke generated during the formation of the light guide pattern portion, thereby preventing the energy of the laser beam from being reduced.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (8)

A light guide plate pattern forming apparatus for forming a plurality of patterned light guide pattern portions on a light guide plate, A pattern design system in which data on a pattern to be formed on the light guide plate is input; A control system connected to the pattern design system and transmitting a position signal corresponding to a coordinate value of each pattern to be formed on the light guide plate; A header moving unit which moves up, down, left and right mechanically according to the position signal received from the control system; A laser system for outputting a laser beam according to a pulse signal synchronized with movement of the header moving unit; A lens unit for allowing the laser beam output from the laser system to focus on the scanning surface of the light guide plate via the header moving unit; Bending prevention means provided to prevent the light guide plate from being bent by local heating of the laser beam; And And an absorption scattering preventing means installed to remove smoke generated while the light guide pattern portion is formed on the light guide plate. The method of claim 1, The header moving part includes an XY moving part mechanically movable in the XY direction, and at least one mirror header part coupled to the XY moving part to reflect the laser beam scanned from the laser system to the light guiding plate. Pattern forming apparatus. The method of claim 2, The XY moving unit is installed in a direction perpendicular to the horizontal guide rail to which the mirror header unit is installed, a horizontal linear motor for supplying power to horizontally reciprocate the mirror header unit with respect to the horizontal guide rail, and the horizontal guide rail. A vertical guide rail and a vertical linear motor for supplying power for vertical reciprocating movement of the horizontal guide rail with respect to the vertical guide rail. The method according to claim 2 or 3, The mirror header part reflects a first mirror header part fixed to a horizontal guide rail corresponding to a beam path axis of the laser system, and a laser beam reflected from the first mirror header part onto a light guide plate and along the horizontal guide rail. And a second mirror header portion coupled to be capable of horizontal movement. The method of claim 1, The bending preventing means includes a plate on which the light guide plate is mounted, and a vacuum unit configured to provide a vacuum passage portion in the plate to provide a vacuum force for vacuum suction of the light guide plate to the plate. The method of claim 1, The plate is a pattern forming apparatus for a light guide plate, characterized in that the heating unit is further installed to transfer heat to the light guide plate to reduce the temperature deviation of the upper and lower surfaces. The method of claim 1, The absorption scattering preventing means is installed on one side of the light guide plate, the light guide plate is installed to supply a gas of normal pressure or more through the blower pipe to the scanning surface of the light guide plate to blow the smoke and cool the light guide plate at the same time. Pattern forming apparatus. The method of claim 7, wherein The other side of the light guide plate pattern forming apparatus for the light guide plate, characterized in that the exhaust portion is further provided to suck out the smoke generated on the light guide plate.