Light Guide Plate

Abstract

The present invention relates to a light guide plate, and more specifically, to a light guide plate that can maintain a constant uniformity of light regardless of size even when cut to fit product specifications after manufacturing, thereby offering excellent versatility, and can increase light utilization efficiency by emitting light with high brightness.

Description

Technology Field

[0001] The present invention relates to a light guide plate, and more specifically, to a free-pattern light guide plate that can maintain a constant uniformity of light regardless of size even when cut to fit product specifications after manufacturing, thereby offering excellent versatility, and can increase light utilization efficiency by emitting light with high brightness. Background Technology

[0002] Light guide plates are components used to transmit emitted light with minimal loss and are generally widely used in the backlights of displays such as LCDs.

[0003] As backlights are being replaced from surface light sources like CCFLs to LEDs, the importance of the light guide plate is growing in order to emit light with high brightness relative to the number of LEDs in order to lower manufacturing costs.

[0004] Generally, light guide plates have patterns such as dots and prisms formed on their surfaces to increase brightness and diffusely reflect light to emit light uniformly.

[0005] However, conventional light guide plates require optimal optical design depending on the size of the product, and consequently, the pattern design of the dot or prism must be changed according to the size of the product, which has a problem of poor versatility.

[0006] In addition, conventional light guide plates could not emit light with high uniformity upwards, and there was a problem of reduced brightness due to light loss. The problem to be solved

[0007] The purpose of the present invention, devised to solve the aforementioned problems, is to provide a light guide plate having a free pattern that can maintain consistent light uniformity regardless of size even when cut to fit product specifications after manufacturing, thereby offering excellent versatility, and can increase light utilization efficiency by emitting light with high brightness. means of solving the problem

[0008] To achieve the above objectives, the light guide plate according to the present invention is a light guide plate having a pattern formed in relief and intaglio on a base light guide plate; the pattern comprises a first unit pattern arranged in a vertical direction and a horizontal direction; a second unit pattern arranged in an inclined direction inside the connection of the first unit pattern; and a triangular non-pattern area in the space between the first unit pattern and the second unit pattern combined; wherein four first unit patterns are combined to form a square small cluster, the small cluster is formed by four second unit patterns interlocking in an X shape, and the four small clusters are combined to form a unit cluster; and the cross-section of the pattern is configured in a semicircular or arc shape.

[0009] The cross-section of the above pattern is characterized by being composed of an asymmetric shape in which the tangent angles at both ends of the pattern have different angles.

[0010] The above pattern is characterized by having tangent angles at both ends such that one end has a 45-degree angle and the other end has a 5-degree angle.

[0011] A small light-gathering area (A) is formed at the center of the small cluster; a unit light-gathering area (B) is formed at the center of the unit cluster; and the small light-gathering area (A) and the unit light-gathering area (B) are formed in the shape of a lens such that their height decreases toward the center of the area.

[0012] The above small light-gathering area (A) is characterized by having an X-shaped lenticular or prism formed where each adjacent vertex of the second unit pattern is connected; and the above unit light-gathering area (B) is characterized by having a lenticular or prism formed in a shape where each adjacent vertex of the first and second unit patterns is connected, forming eight diameter lines passing through the center of a virtual circle.

[0013] The area of ​​the non-pattern region among the above unit clusters is characterized by being formed in the range of 5 to 15% of the area of ​​the above unit clusters.

[0014] The above unit pattern is characterized by having a width of 0.3 to 1 mm and a height of 0.024 to 1 mm, and the ratio of the width to the height is formed in the range of 1:1 to 1:0.8. Effects of the invention

[0015] As seen above, the light guide plate according to the present invention has four small cluster regions formed within a unit cluster region, and since light uniformity can be primarily increased by the small light-gathering region (A) of each small cluster region and secondarily increased by the unit light-gathering region (B) of the unit cluster region, an excellent effect of maximizing light uniformity occurs.

[0016] In addition, an excellent effect is achieved in which light can be emitted with high brightness through uniform light diffusion and waveguide of the small light-gathering area (A) and the unit light-gathering area (B). Brief explanation of the drawing

[0017] FIG. 1 is a schematic plan view illustrating the pattern of a light guide plate according to a preferred embodiment of the present invention, and FIG. 2 is a detailed enlarged view of a unit cluster for the pattern of FIG. 1. FIG. 3 illustrates the cross-sectional shape of a pattern according to a preferred embodiment of the present invention. Figures 4 and 5 are graphs comparing light extraction efficiency according to the specifications of a pattern according to a preferred embodiment of the present invention. FIG. 6 illustrates the shape and cross-section of the first and second unit patterns according to a preferred embodiment of the present invention, and FIG. 7 is a detailed configuration diagram of the unit pattern. FIG. 8 illustrates the light path of a unit light-gathering area (B) according to a preferred embodiment of the present invention. FIG. 9 is a detailed enlarged view of a unit cluster showing that a small light-gathering area (A) and a unit light-gathering area (B) are formed in the shape of a lens according to another embodiment of the present invention. FIG. 10 is a detailed enlarged view of a unit cluster in which a lenticular or prism is formed in a small light-gathering area (A) and a unit light-gathering area (B) according to another embodiment of the present invention. Specific details for implementing the invention

[0018] Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

[0019] FIG. 1 is a schematic plan view illustrating the pattern of a light guide plate according to a preferred embodiment of the present invention, and FIG. 2 is a detailed enlarged view of a unit cluster for the pattern of FIG. 1.

[0020] Referring to FIGS. 1 and 2, a light guide plate according to the present invention has a pattern formed in relief or intaglio on a base substrate, wherein rectangular unit patterns are continuously arranged and triangular non-pattern areas are formed in intaglio between the unit patterns by the combination of the unit patterns.

[0021] The above unit pattern may be configured to include a first unit pattern (11) arranged in a vertical direction and a horizontal direction, and a second unit pattern (15) arranged in an inclined direction inside the first unit pattern.

[0022] Four of the first unit patterns (11) are combined to form a square small cluster, and the small cluster is formed by four second unit patterns (13) interlocking in an X shape.

[0023] And the above small cluster includes four non-patterned areas (15) of a triangular shape.

[0024] Here, the non-pattern area (15) may be configured as a lens shape composed of a curve rather than a triangle.

[0025] When configured in a lens shape, it is possible to implement a pattern that is more compact than a triangle.

[0026] The width and height of the unit pattern and the shape and size of the non-pattern area (15) have an important effect on the uniformity and brightness of the incident light, so an optimized design is required.

[0027] In order to uniformly transmit light emitted from the bottom to the top, if the width is larger or lower than the height, a light spot problem in which light is concentrated in a local area may occur. Therefore, it is desirable to form the width of the unit pattern to be 0.3 to 1 mm and the height to be 0.025 to 1 mm, and to design the ratio of the width to the height of the pattern to be 1:1 to 1:0.8.

[0028] Then, the four small clusters are combined to form a unit cluster. The unit cluster includes 16 non-patterned areas (15) in the shape of triangles. Each non-patterned area (15) affects the uniformity and brightness of the incident light. If the area of ​​the non-patterned area (15) is excessively large, uniformity of brightness cannot be secured, and if it is excessively small, the overall brightness may decrease due to loss of brightness, so an optimal design is required.

[0029] FIG. 3 illustrates the cross-sectional shape of a pattern according to a preferred embodiment of the present invention.

[0030] The cross-section of the pattern in Fig. 2 can be configured in a semicircular or arc shape.

[0031] As described above, when configured in a semicircular or arc shape, a dead zone occurs on each main surface when configured in an angle, whereas in the case of a semicircular or arc shape, light can be evenly dispersed upward without a dead zone.

[0032] The pattern of FIG. 3 has a cross-section of the pattern that is asymmetric. In particular, it can be configured as an asymmetric shape in which the tangent angles at both ends of the pattern are different, and preferably, one end can be formed to have a 45-degree angle and the other end to have a 5-degree angle.

[0033] Here, if one end is greater than 45 degrees, the width of the pattern must be widened for an asymmetric configuration, and if the other end is greater than 5 degrees, the light dispersion effect due to the asymmetric structure is reduced, so it is desirable to form the tangent angle of one end at 45 degrees and the tangent angle of the other end at 5 degrees.

[0034] When an asymmetric structure as described above is formed, the light dispersion effect is doubled, and the brightness can be significantly improved compared to a light guide plate structure that is semicircular or arc-shaped.

[0035] Figures 4 and 5 are graphs comparing light extraction efficiency according to the specifications of a pattern according to a preferred embodiment of the present invention.

[0036] Referring to Figures 4 and 5, the cross-section of the pattern is arc-shaped and asymmetric, with one end of the pattern having a 45-degree angle and the other end having a 5-degree angle, and the height of the pattern unit is designed to be 55 µm, and the effect was verified through optical simulation for four cases (CASE 1 to 4) depending on the size of the unit cluster and the size of the non-pattern area.

[0037] CASE 1 CASE 2 CASE 3 CASE 4 Unit cluster area 51.84 ㎟(7.2x7.2) 38.1924 ㎟(6.18x6.18) 6.8324 ㎟(5.18x5.18) 26.8324 ㎟(5.18x5.18) Non-patterned area 23.088 mm²(1.85x1.56x1 / 2x16) 6.656 mm²(1.3x0.64x1 / 2x16) .4336 mm²(0.78x0.39x1 / 2x16) 1.792 mm²(0.7x0.32x1 / 2x16) Non-pattern area ratio 44. 5% 17.4% 9% 6.7 %

[0038] As a result, CASE 3 was confirmed to have the best light efficiency, and CASE 3 has a unit cluster area of ​​26.83 mm² 2 Set to (5.08 x 5.08), and the area of ​​the non-patterned region is 2.4336mm 2 It was confirmed that the light efficiency was highest when designed as (0.78 x 0.39 x 1 / 2 x 16).

[0039] Ultimately, it was confirmed that the pattern of the light guide plate according to the present invention significantly affects the uniformity and brightness of light depending on the shape of the pattern, the area of ​​the unit cluster, and the area of ​​the non-patterned region within the unit cluster.

[0040] As the area of ​​the non-pattern area within the unit cluster area decreases, the light efficiency increases. The light efficiency was highest when the non-pattern area was about 1 / 10 of the total unit cluster area (CASE 3, 9%), but when the area ratio decreased to 6.7% (CASE 4), the light efficiency actually decreased. Therefore, it is desirable to design the non-pattern area to be 5 to 15% of the area of ​​the unit cluster area.

[0041] And the above non-pattern area (15) is formed in a triangular shape, and since the four non-pattern areas (15) formed in the small cluster are designed as a continuous pattern type in which two pairs are formed facing each other in vertical and horizontal directions, it can be freely cut and used regardless of the size of the light guide plate, thus producing an excellent effect of great versatility.

[0042] In addition, because the virtual connecting lines of the four pairs of non-patterned areas (15) inside are formed in a rhombus shape by the second unit patterns in the diagonal direction of the unit cluster, the light guide plate can maintain uniform brightness even when cut in the diagonal direction as well as in the vertical and horizontal directions.

[0043] FIG. 6 is a detailed enlarged view of a unit cluster according to another embodiment of the present invention, and FIG. 7 is a detailed configuration diagram of the unit pattern of FIG. 6.

[0044] Referring to FIGS. 6 and 7, the first unit pattern (11) is formed such that the connecting portions (112) at both ends of the body portion (111) both have a 45-degree angle, and the second unit pattern (13) is formed such that the angle of the connecting portion connected to the first unit pattern (11) is 45 degrees, but the angle of the connecting portion connected to the second unit pattern (13) is 90 degrees. Four first unit patterns (11) are connected to form a square small cluster, and four second unit patterns (13) are connected in an X-shape at the center of the small cluster to form a small light-gathering area (A).

[0045] The above small light-gathering area (A) is joined by the connecting part (132) of the second unit pattern, and since the connecting part (132) of the second unit pattern has an angle of 90 degrees, four second unit patterns (20) are joined to form a small light-gathering area (A) in the shape of a concave lens.

[0046] The center of the above small light-gathering area (A) has a slanted or curved shape so that its height is reduced.

[0047] Therefore, light incident from the bottom is diffused through the small light-gathering region (A) like a concave lens and uniformly guided to the upper part of the small cluster region to emit light.

[0048] The above unit light-gathering area (B) is an area formed by combining the joints of four first unit patterns (11) and four second unit patterns (13), and since the joints of each unit pattern have a 45-degree angle and are joined together, connecting the perimeters of the joints forms a circle.

[0049] The above unit light-gathering area (B) is formed in the shape of a concave lens that has a slope and a lower height as it approaches the center of the circle, and as a result, light incident from below can be effectively diffused as shown in FIG. 8, thereby increasing the uniformity of the light.

[0050] That is, one unit cluster includes four small light-gathering regions (A) and one unit light-gathering region (B), and since the four small light-gathering regions (A) uniformly emit light over each small cluster region and at the same time the one unit light-gathering region (B) uniformly guides and emits light over the unit cluster region, it has an excellent effect of maximizing light emission efficiency.

[0051] The above embodiment relates to a case where both ends of each unit pattern are combined with other unit patterns in a puzzle-like manner to form a small light-gathering area (A) and a unit light-gathering area (B), but the small light-gathering area (A) and the unit light-gathering area (B) may also be formed by processing them into a concave lens shape as shown in FIG. 9 after forming the pattern as shown in FIG. 1.

[0052] In addition, as shown in FIG. 10, after forming a pattern as in FIG. 1, a prism or lenticular can be formed on the small light-gathering area (A) and the unit light-gathering area (B) to enable uniform light emission of high brightness.

[0053] More specifically, when a pattern is formed as in FIG. 1, the small light-gathering area (A) forms a prism or lenticular on the line connecting the four adjacent vertices of the second unit pattern (13) in a diagonal direction. And the unit light-gathering area (B) also forms a prism or lenticular on the line passing through the center of the circle among the eight adjacent vertices of the first unit pattern (11) and the second unit pattern (13).

[0054] Accordingly, a small light-gathering region (A) and a unit light-gathering region (B) are formed, such as in Fig. 10, where a prism or lenticular is formed.

[0055] That is, the plan view of the small light-gathering region (A) and the unit light-gathering region (B) formed with the lenticular or prism is formed identically to the plan view, although the cross-sectional view is different as in the embodiment of FIG. 4. Below, we will examine the method for manufacturing a light guide plate according to the present invention as described above.

[0056] The light guide plate according to the present invention can be manufactured by a roll pattern transfer method, injection molding, and die casting method.

[0057] When manufactured by a roll pattern transfer method, first, a roll is prepared by attaching a stamper having a pattern according to the present invention formed in relief and intaglio to the outer edge of the roller, or by directly forming a pattern on the outer edge of the upper roller.

[0058] A base light guide plate made of a synthetic resin such as PMMA is extruded onto the roll prepared as described above to form a pattern on the surface of the light guide plate.

[0059] In addition, when manufactured by an injection molding method, a light guide plate with a pattern formed thereon can be manufactured by preparing a stamper mold having a pattern formed thereon in intaglio, injecting a synthetic resin into the stamper mold, and then injecting.

[0060] In the case of manufacturing by a die-casting method, a light guide plate with a pattern formed thereon can be manufactured by preparing a stamper mold in which a pattern according to the present invention is formed in relief and intaglio, injecting a liquid synthetic resin into the stamper, and then compressing it.

[0061] Although the detailed description of the present invention described above has been explained with reference to preferred embodiments of the present invention, the scope of protection of the present invention is not limited to the above embodiments, and those skilled in the art will understand that various modifications and changes can be made to the present invention within the scope of the spirit and technical scope of the present invention without departing from the spirit and technical scope of the present invention. Explanation of the symbols

[0062] 11: 1st Unit Pattern 13: 2nd Unit Pattern 15: Non-pattern area A: Small light-concentrating area B: Unit light-concentrating area

Claims

Claim 1 A light guide plate having a pattern formed in relief and intaglio on a base light guide plate; wherein the pattern comprises a first unit pattern arranged in a vertical direction and a horizontal direction; a second unit pattern arranged in an inclined direction inside the connection of the first unit pattern; and a triangular non-pattern area in the space between the first unit pattern and the second unit pattern; wherein four first unit patterns are combined to form a square small cluster, the small cluster is formed by four second unit patterns interlocking in an X shape, and the four small clusters are combined to form a unit cluster; wherein the cross-section of the pattern is configured in a semicircular or arc shape, but is configured in an asymmetrical shape where both ends of the pattern have different angles; and wherein one end of the pattern is formed to have a 45-degree angle and the other end to have a 5-degree angle. Claim 2 delete Claim 3 delete Claim 4 A light guide plate according to claim 1, wherein a small light-gathering area (A) is formed at the center of the small cluster; a unit light-gathering area (B) is formed at the center of the unit cluster; and the small light-gathering area (A) and the unit light-gathering area (B) are formed in a lens shape such that their height decreases toward the center of the area. Claim 5 A light guide plate according to claim 4, wherein the small light-gathering area (A) is formed with an X-shaped lenticular or prism in which adjacent vertices of the second unit pattern are connected; and the unit light-gathering area (B) is formed with a lenticular or prism in which adjacent vertices of the first and second unit patterns are connected to form eight diameter lines passing through the center of a virtual circle. Claim 6 A light guide plate according to claim 1, characterized in that the area of ​​the non-pattern region among the unit clusters is formed in the range of 5 to 15% of the unit cluster area. Claim 7 A light guide plate according to claim 1, characterized in that the width of the first and second unit patterns is formed to be 0.3 to 1 mm and the height to be 0.024 to 1 mm, and the ratio of the width to the height is formed to be in the range of 1:1 to 1:0.8.

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