KR101620021B1 - Method for manufacturing light guide plate with pattern and light guide plate manufactured using thereof - Google Patents

Method for manufacturing light guide plate with pattern and light guide plate manufactured using thereof Download PDF

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Publication number
KR101620021B1
KR101620021B1 KR1020150125113A KR20150125113A KR101620021B1 KR 101620021 B1 KR101620021 B1 KR 101620021B1 KR 1020150125113 A KR1020150125113 A KR 1020150125113A KR 20150125113 A KR20150125113 A KR 20150125113A KR 101620021 B1 KR101620021 B1 KR 101620021B1
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KR
South Korea
Prior art keywords
light guide
guide plate
pattern
byte
light
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KR1020150125113A
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Korean (ko)
Inventor
임성근
장종민
최기준
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동양산업(주)
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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0065—Manufacturing aspects; Material aspects
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0013—Means for improving the coupling-in of light from the light source into the light guide
    • G02B6/0023—Means for improving the coupling-in of light from the light source into the light guide provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
    • G02B6/0025—Diffusing sheet or layer; Prismatic sheet or layer
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133615—Edge-illuminating devices, i.e. illuminating from the side

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Nonlinear Science (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Mathematical Physics (AREA)
  • Chemical & Material Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Planar Illumination Modules (AREA)

Abstract

The present invention relates to a method of manufacturing a light guide plate with a pattern and the light guide plate manufactured thereby. The method for manufacturing a light guide plate with a pattern comprises the steps of: carving transverse bites spaced apart from each other with a preset distance on a mold for manufacturing the light guide plates; carving longitudinal bites to overlap the positions where the transverse bites are carved so that a cross engraved pattern is formed; and molding the light guide plate with the mold having the cross engraved pattern so that an embossing pattern corresponding to the engraved pattern is formed on the bottom surface of the light guide plate, wherein the transverse and longitudinal bites have a prism shape. According to the present invention, by forming a composite pattern with the transverse and longitudinal patterns in a cross form, on a light guide plate, it is possible to increase luminance through diffusion of light while reducing a loss of light of a backlight device. Thus, the number of optical sheets stacked on the top surface of the light guide plate may be reduced and a wide viewing angle may be achieved.

Description

[0001] The present invention relates to a method of manufacturing a light guide plate for pattern formation, and a light guide plate manufactured by the method,

The present invention relates to a method of manufacturing a light guide plate for pattern formation and a light guide plate manufactured thereby.

In general, since a liquid crystal display (LCD) is a light-receiving element that can not emit light itself, unlike a CRT (Cathode-Ray Tube), a backlight unit capable of maintaining uniform brightness throughout the liquid crystal display need.

The backlight unit includes a light source for generating light and a light guide plate for supplying light generated from the light source to the liquid crystal panel.

The light guide plate is a light switching element that receives light from a plurality of point light sources from an LED light source disposed on a side surface, converts light incident from the LED light source into total light through total internal reflection, and emits the light upward. The LED light source may be configured as an LED array in which a plurality of LED packages are mounted on a substrate at regular intervals.

The light incident from the LED light source into the light guide plate has an uneven light distribution through reflection, refraction, transmission, and the like, and a pattern is formed on the light guide plate to uniformize the light and minimize light loss.

Further, since the LED light source disposed on the side surface of the light guide plate is a point light source and has a high light directivity, a portion having a high light intensity is present at a portion close to the LED light source, while a light portion appears at a portion distant from the LED light source. As a result, there arises a problem that the uniformity of the luminance is lowered on the display screen of the liquid crystal display device. In order to solve such a problem, the diameter of the light-incoming portion of the light guide plate is made smaller or the density is lowered, and the diameter of the dot is increased or the density is increased toward the central region and the light-

On the other hand, in a backlight unit of a liquid crystal display device, a reflective sheet, a prism sheet, and a diffusion sheet are used to uniformly diffuse light while reducing light loss.

The reflective sheet is disposed on the lower side of the light guide plate and reflects light leaking from the light guide plate to the lower side to improve the brightness of the backlight device.

The prism sheet concentrates light so that light emitted from the light guide plate at various output angles can be advanced in the upward direction, thereby improving the luminance in the vertical direction.

The diffusion sheet diffuses the light emitted from the light guide plate and the prism sheet primarily and secondarily so that finally uniform light is emitted.

In such a backlight device, since a plurality of optical sheets including a diffusion sheet and a prism sheet are used to control optical characteristics such as brightness and uniformity, the slimming of the backlight device is hindered due to the stacking of many optical sheets, There is a problem to be done.

In the backlight device according to the conventional technique, the light emitted is focused only on the vertical upper side. In this case, a high luminance can be exhibited in the vertical direction of the backlight device, but the luminance is relatively low in the side direction, which causes a problem that the viewing angle becomes narrow.

Korean Patent Application No. 10-2011-0101655

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a light guide plate capable of reducing the light loss of the backlight unit and improving the brightness through diffusion of light, thereby reducing the number of optical sheets stacked on the upper surface of the light guide plate And to provide a light guide plate for pattern formation which can exhibit a wide viewing angle and a light guide plate manufactured thereby.

According to another aspect of the present invention, there is provided a method of manufacturing a light guide plate for forming a pattern, the method comprising the steps of: Forming a cross-shaped engraved pattern by further embossing the longitudinal bytes so that the crossbot is superimposed on the embossed position in the mold; Forming a light guide plate using the mold having the engraved pattern formed thereon to form a relief pattern corresponding to the engraved pattern on a lower surface of the light guide plate; Wherein the horizontal byte and the vertical byte have a prism shape.

In addition, the vertical bytes are oriented so as to be superimposed on the center of the position where the horizontal bytes are embossed.

Further, in the horizontal byte and the vertical byte, a section passing through the center in the longitudinal direction has a trapezoidal shape, and a section passing through the center in the width direction has a triangular shape.

Also, the angle b of the horizontal byte and the angle c of the vertical byte are 60 °, 120 ° or 120 ° and 60 °, respectively.

A light guide plate according to another embodiment of the present invention is manufactured according to the light guide plate manufacturing method.

In the light guide plate according to another embodiment of the present invention, a horizontal long pattern in the shape of a boss and a long vertical pattern in the form of a cross over the horizontal pattern are formed on the lower surface of the light guide plate, Shape.

In the horizontal pattern and the vertical pattern, the cross section passing through the center in the longitudinal direction has a trapezoidal shape, and the cross section passing through the center in the width direction has a triangular shape.

The angle (e) of the horizontal pattern and the angle (f) of the vertical pattern are 60 °, 120 ° or 120 ° and 60 °, respectively.

According to the present invention, it is possible to reduce the number of optical sheets stacked on the upper surface of the light guide plate by improving the brightness through diffusion of light while reducing the light loss of the backlight unit by forming a composite pattern having a cross pattern and a cross pattern in the light guide plate And at the same time, a wide viewing angle can be provided, and a light guide plate manufactured by the method can be provided.

1A is a cross-sectional view taken along the line AA 'in FIG. 1A, and FIG. 1B is a cross-sectional view taken along the line AA' in FIG. 1A. FIGS. 1A to 1C are cross- 1c is a cross-sectional view taken along line BB 'of FIG. 1a.
FIG. 2A is a plan view of a vertical byte, FIG. 2B is a cross-sectional view taken along line CC 'of FIG. 2A, and FIG. 2c is a sectional view taken along the line DD 'in FIG. 2A.
FIGS. 3A to 3C are views showing a state in which a horizontal byte and a vertical byte are combined for pattern formation according to an embodiment of the present invention. FIG. 3A is a plan view of a state in which a horizontal byte and a vertical byte are combined, 3A is a cross-sectional view taken along the line EE 'of FIG. 3A, and FIG. 3C is a cross-sectional view taken along the line FF' of FIG. 3A.
FIG. 4A is a schematic cross-sectional view of a conventional light guide plate, and FIG. 4B is a schematic cross-sectional view of a light guide plate having a composite pattern according to an embodiment of the present invention.
5A to 5D are views sequentially illustrating a method of manufacturing a light guide plate for pattern formation according to an embodiment of the present invention.
6 is a perspective view illustrating a composite pattern formed on a light guide plate according to an embodiment of the present invention.
7 is an enlarged photograph of a light guide plate having a composite pattern according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, like reference numerals refer to like elements throughout. The same reference numerals in the drawings denote like elements throughout the drawings.

1A is a cross-sectional view taken along the line AA 'in FIG. 1A, and FIG. 1B is a cross-sectional view taken along the line AA' in FIG. 1A. FIGS. 1A to 1C are cross- 1c is a cross-sectional view taken along line BB 'of FIG. 1a.

FIG. 2A is a plan view of a vertical byte, FIG. 2B is a cross-sectional view taken along line CC 'of FIG. 2A, and FIG. 2c is a sectional view taken along the line DD 'in FIG. 2A.

FIGS. 3A to 3C are views showing a state in which a horizontal byte and a vertical byte are combined for pattern formation according to an embodiment of the present invention. FIG. 3A is a plan view of a state in which a horizontal byte and a vertical byte are combined, 3A is a cross-sectional view taken along the line EE 'of FIG. 3A, and FIG. 3C is a cross-sectional view taken along the line FF' of FIG. 3A.

A method of manufacturing a light guide plate for pattern formation according to the present invention is to form a cross-shaped composite pattern on the lower surface of a light guide plate to improve the brightness of a backlight unit and to exhibit a wide viewing angle. Here, the lower surface of the light guide plate refers to a surface opposite to the light emitting surface through the backlight unit.

To this end, in the present invention, a cruciform composite pattern is embossed at an engraved pattern by using a lateral bite and a longitudinal bite in a mold for manufacturing a light guide plate, and a light guide plate is formed by using such a mold, Thereby forming a composite pattern of a relief shape corresponding to the composite pattern of FIG.

First, a horizontal byte 110 and a vertical byte 120 for forming a composite pattern on a metal mold at a negative angle will be described.

1A to 1C, the lateral bite 110 has a prism shape. A cross section along the line AA '(a cross section passing through the center in the longitudinal direction) has a trapezoidal shape, and a cross section along the line BB' (crossing the center in the width direction Section) may have a triangular shape.

2A to 2C, the vertical byte 120 has a prism shape. The longitudinal byte 120 has a long shape, and a cross section along a line CC 'in FIG. 2A has a triangular shape and a cross-section along a line DD' Section) may have a trapezoidal shape.

3A to 3C, a composite pattern 130 in which the horizontal byte 110 and the vertical byte 120 are combined is shown. The composite pattern 130 includes a combination of a horizontal pattern 131 corresponding to the shape of the horizontal byte 110 and a vertical pattern 132 corresponding to the shape of the vertical byte 120. In the figure, the composite pattern 130 is shown in a relief shape.

In order to form the engraved composite pattern 130 in the mold, after the horizontal byte 110 is embossed, the vertical byte 120 is further embossed so as to be superimposed on the center of the position where the horizontal byte 110 is embossed So that a cross-shaped engraved pattern is formed.

4A is a schematic cross-sectional view of a conventional light guide plate 10, and FIG. 4B is a schematic cross-sectional view of a light guide plate 100 having a composite pattern according to an embodiment of the present invention.

In the conventional light guide plate 10, a generally semicircular protrusion is spaced apart from the bottom surface.

In contrast, in the light guide plate 100 of the present invention, a composite pattern in which a horizontal pattern 101 and a vertical pattern 102 having a shape corresponding to a horizontal byte 110 and a vertical byte 120 are crossed in a cross shape is formed .

5A to 5D are views sequentially illustrating a method of manufacturing a light guide plate for pattern formation according to an embodiment of the present invention.

First, referring to FIG. 5A, a horizontal cutting tool 110 is placed on a mold 200 for manufacturing a light guide plate so as to be spaced apart from each other by a predetermined distance. Accordingly, in the mold 200, the transverse patterns 210 having a negative shape corresponding to the shapes of the side tools 110 are formed apart from each other.

Next, referring to FIG. 5B, the vertical bite 120 is additionally placed in the center of the position where the horizontal bite 110 is embossed in the mold 200. Accordingly, the metal pattern 200 is formed with vertical patterns 220 to overlap with the horizontal patterns 210, so that the overall engraved engraved patterns are spaced apart from each other.

Next, referring to FIG. 5C, a light guide plate 100 is formed using a mold 200 having a complex pattern of engraved patterns.

5D, the mold 200 is removed to form a relief pattern corresponding to the relief pattern of the mold 200 on the lower surface of the light guide plate 100. Referring to FIG. The light guide plate 100 has a cross-shaped composite pattern in which the horizontal pattern 101 and the vertical pattern 102 are combined.

6 is a perspective view showing a composite pattern formed on a lower surface of the light guide plate 100 according to an embodiment of the present invention. The light guide plate 100 has a horizontal pattern 101 having a shape corresponding to the horizontal byte 110 and a vertical pattern 102 having a shape corresponding to the vertical byte 120. The vertical pattern 102 is formed to overlap the center of the horizontal pattern 101 so as to intersect with the horizontal pattern 101.

In the horizontal pattern 101 and the vertical pattern 102, the cross section passing through the center in the longitudinal direction has a trapezoidal shape, and the cross section passing through the center in the width direction has a triangular shape.

7 is an enlarged photograph of a light guide plate having a composite pattern according to an embodiment of the present invention. As described above, the cross-shaped composite patterns are formed on the lower surface of the light guide plate 100 with a density different from that of the cross-shaped composite patterns, and are formed at random angles.

Such a composite pattern can uniformly diffuse the condensed light to the upper side to dispense with a diffusion sheet, and arrange the cross patterns randomly, thereby suppressing the generation of interference fringes.

In addition, the composite pattern makes use of total reflection and refraction, not scattering, to obtain higher luminance quality than a screen using scattering.

Therefore, when the light guide plate 100 manufactured according to the method of manufacturing the light guide plate of the present invention is used, the backlight unit does not deteriorate the optical characteristics even if the number of the optical sheets stacked on the upper side of the light guide plate 100 is reduced, The manufacturing cost can be reduced and a wide viewing angle can be exhibited.

The following table shows the luminance through the backlight unit using such a light guide plate by changing the angle b of the horizontal byte 110 and the angle c of the vertical byte 120.

Here, the unit of luminance is knit (nit = cd / m < 2 >) and Center refers to the front surface of the backlight unit. When center is 90 °, Area A + refers to 80 °, Area A refers to 50 °, and Area B refers to 40 °.

Figure 112015085984240-pat00001

Figure 112015085984240-pat00002

Figure 112015085984240-pat00003

Figure 112015085984240-pat00004

Referring to Table 1, when the angle b of the horizontal byte 110 is 60 degrees and the angle c of the vertical byte 120 is 120 degrees, or when the angle b of the horizontal byte 110 ) Is 120 °, and the angle b of the vertical byte 120 is 60 °, it can be seen that the luminance is highest in Center, Area A +, Area A, and Area B.

Therefore, when the mold 200 is embossed with the horizontal and vertical battens 110 and 120 to manufacture the light guide plate 100, the angle b of the horizontal byte and the angle c of the vertical byte are 60 °, 120 ° or 120 ° and 60 °, it was found that the molded light guide plate 100 had excellent luminance characteristics and a wide viewing angle.

Table 2 shows the luminance characteristics of the backlight unit using the light guide plate of the present invention in the entire viewing angle range. Here, Ref. Refers to a backlight unit using a conventional light guide plate having a semicircular protrusion, and WS refers to a backlight unit using the light guide plate of the present invention.

Figure 112015085984240-pat00005

Figure 112015085984240-pat00006

Referring to Table 2, when the front face of the backlight unit is set to 0 DEG, the luminance of the backlight unit of the present invention is 25% and 21% at the right and left viewing angles of 30 DEG in comparison with the conventional backlight units at the respective viewing angles of left and right It can be confirmed that the luminance is improved and the luminance is improved by 20 to 40% at an angle of 30 degrees or more.

The angle b of the horizontal byte and the angle c of the vertical byte correspond to the angle h of the horizontal pattern 101 of the light guide plate 100 and the angle f of the vertical pattern 102 Respectively. Therefore, when the angle? E of the horizontal pattern 101 of the light guide plate 100 and the angle f of the vertical pattern 102 are 60 °, 120 °, 120 °, and 60 °, Is excellent in luminance characteristics and has a wide viewing angle.

As described above, according to the method of manufacturing the light guide plate of the present invention and the light guide plate manufactured by the method, by forming the composite pattern in which the crossbelt 110 having the prism shape and the crossbelt 120 are combined in the cross shape, The light loss can be reduced by the light condensing effect and the total reflection and refraction of the light can be used without the diffusion sheet to obtain a higher luminance quality than the screen using scattering.

Accordingly, it is possible to reduce the number of optical sheets stacked on the upper side of the light guide plate, to make the backlight unit slim, to reduce the manufacturing cost, and to have a wide viewing angle.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention will be.

100: light guide plate
101: Horizontal pattern
102: Vertical pattern
110: horizontal byte
120: Vertical byte
130: composite pattern
200: Mold
210: horizontal pattern
220: Vertical pattern

Claims (8)

A method for manufacturing a light guide plate for pattern formation,
A method for manufacturing a light guide plate, comprising the steps of:
Forming a cross-shaped engraved pattern by further embossing the longitudinal bytes so that the crossbot is superimposed on the embossed position in the mold;
Forming a light guide plate using the mold having the engraved pattern formed thereon to form a relief pattern corresponding to the engraved pattern on a lower surface of the light guide plate;
Lt; / RTI >
Wherein the horizontal byte and the vertical byte have a prism shape,
Wherein the vertical bytes are oriented so as to be superposed on the center of the position where the horizontal bytes are embossed,
Wherein a cross section passing through the center in the longitudinal direction of the horizontal byte and the vertical byte has a trapezoidal shape and a cross section passing through the center of the width direction has a triangular shape. delete delete The method according to claim 1,
Wherein the angle b of the horizontal byte and the angle c of the vertical byte are 60 °, 120 °, 120 °, and 60 °, respectively. delete delete delete delete
KR1020150125113A 2015-09-03 2015-09-03 Method for manufacturing light guide plate with pattern and light guide plate manufactured using thereof KR101620021B1 (en)

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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007311330A (en) 2006-05-22 2007-11-29 Taesan Lcd Co Ltd Manufacturing method of light guide plate of backlight

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007311330A (en) 2006-05-22 2007-11-29 Taesan Lcd Co Ltd Manufacturing method of light guide plate of backlight

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