KR101653752B1 - Structure of light guide plate with a tube manifold - Google Patents

Abstract

The present invention relates to a structure of a light guide plate for back light. This light guide plate structure includes a planar light guide plate main body having a uniform thickness and a wedge-shaped light receiver portion formed on the light source side of the main body. In particular, the light-receiving portion includes a light guide hole formed in parallel to the light incidence surface and extending in the direction of the optical axis from the incident surface toward the back surface in the direction of the optical axis, and a hollow guide tube having an outer surface closely fitted on the inner surface of the guide hole. And a tube manifold which is integrally formed with the plurality of guide holes and which has an upper end and a lower end folded toward the rear body side and is pressed and coupled to the upper surface and the lower surface of the light receiving portion, respectively. According to the light guide plate structure of the present invention, loss due to light spreading can be reduced and luminance characteristics can be improved. On the other hand, the tube manifold can be pressed and attached to the light receiving unit.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a light guide plate having a tube manifold,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light guide plate, and more specifically, to a structure of a light guide plate applied to a surface light source device for backlighting such as a liquid crystal display.

Background Art [0002] In recent years, in accordance with a demand for thinning of mobile devices, a surface light source device applied to a device is also required to be gradually thinned. On the other hand, even if the thickness of the planar light guide plate can be reduced for thinning the surface light source device, there is a limit in reducing the height of the light source made of the LED. Therefore, in the case of using a thin flat light guide plate, the height of the light source becomes larger than the thickness of the incident surface of the light guide plate, so that the light source arranged opposite to the incident surface of the light guide plate becomes higher than the upper surface of the light guide plate.

When the light source is higher than the light guide plate, all of the light supplied from the light source does not enter the incident surface of the light guide plate, and a part of the light leaks to the outside. In order to solve such a problem, a wedge-shaped light receiving portion called "edge" having a larger thickness than the main body of the light guide plate is provided on one side of the planar light guide plate main body to enlarge the incident surface, As shown in Fig.

FIG. 1 illustrates a planar light source device using the light guide plate having such a structure. Referring to FIG. 1, the surface light source device 1 uses a light guide plate 2 having a light receiving portion 4 having a larger thickness than the light guide plate main body 3. Here, the light guide plate 2 is composed of a planar light guide plate main body 3 having a uniform thickness and a wedge-shaped light receiving portion 4 formed on one side of the main body 3. A reflection pattern is formed on the back surface of the light guide plate main body 3, and a lenticular lens 6 is formed on the surface. The light receiving portion 4 includes an incident surface on the front surface and an inclined surface 5 formed toward the upper surface of the light guide plate main body 3 at the upper end of the incident surface.

On the other hand, the thickness of the front surface of the light receiving portion 4 is equal to or larger than the height of the light source L. The light supplied from the light source L can be efficiently transmitted to the light receiving section 4 by making the cross-sectional thickness of the light receiving section 4 larger than the height of the light source L in the surface light source device 1. The light transmitted to the light receiving portion 4 is guided to the light guide plate main body 3, spreads over the entire surface, is reflected by the reflection pattern, and is output to the outside through the surface emitting surface of the light guide plate main body 3. At this time, the light output from the exit surface has a large directivity characteristic in the lenticular lens 6.

According to the surface light source device having such a structure, it is possible to improve the light utilization efficiency and reduce the thickness of the surface light source device. However, according to this structure, the light advancing in the direction inclined with respect to the optical axis of the light source L in the light receiving portion 4 becomes wider in the lateral direction as it is expanded and reflected on the inclined surface 5, . As a result, light emitted from the inclined plane 5 leaks to the side surface of the light guide plate 2 (see arrow a), while light is incident in the lateral direction of the lenticular lens 6 and light leaks from the lenticular lens 6 (Refer to (b)), problems such as a decrease in light utilization efficiency due to loss of light amount and a decrease in luminance uniformity are caused.

Thus, there has been an attempt to prevent light leakage by forming a plurality of directivity patterns 7 on the surface of the inclined surface 5 of the light receiving portion 4. [ However, the light reflected by the pattern 7 is more likely to diffuse in the left and right directions than in the case of only the inclined surface 5, and thus the spread of light becomes greater, This makes it easier to leak (see arrow ⓒ). Further, in the case where the light guide plate main body 3 has an optical pattern such as the lenticular lens 6, the light easily leaks from the pattern. As a result, problems such as a decrease in light utilization efficiency and a decrease in luminance uniformity due to a loss of light amount still or more seriously occur.

On the other hand, referring to FIG. 2, there has been an attempt to form a light diffusion pattern on the incident surface of the light receiving section 4 to broaden the light in the lateral direction. In other words, it is possible to prevent the side edge portion of the light guide plate 2 from becoming relatively dark by diffusing the light incident thereon using the light diffusion pattern 8 widely in the left and right and lateral directions.

But in this case:

The light supplied from the light source L is reflected and dispersed to the left and right in front of the incident surface. In this process, a considerable amount of light loss occurs.

By forcibly diffusing a certain amount of light from before entering the light receiving portion 4, the overall brightness and brightness of the light guide plate 2 are seriously deteriorated;

And it is difficult for this method to be actually applied. Therefore, in reality, when the incidence side is long left and right,

A method of disposing a plurality of light sources L apart from each other;

.

<Prior Art Literature>

Published Patent No. 10-2010-0041911

Published patent application No. 10-2011-0083490

Published patent application No. 10-2011-0101050

Published Japanese Patent Application No. 10-2013-0105371

The present invention has been proposed to solve the problems of the above-mentioned prior arts. It is an object of the present invention to provide an improved light guide plate structure that can prevent light leakage and luminance uniformity deterioration in a light guide plate applied to a surface light source device for back light. The present inventor has designed the light guide plate so that the light supplied from the light source has directivity in the direction of the optical axis when the light enters the incident surface of the light receiving portion in the beginning and structurally reinforces the light guide plate by applying a tube manifold thereto, The present invention has been completed.

The light guide structure of the present invention comprises:

And a wedge-shaped light receiving unit formed on the light source side of the main body and having a thickness larger than that of the main body, wherein the light receiving unit is formed with a light incident surface on the front surface and an inclined surface formed on an upper surface of the light incident surface, Based on a conventional light guide structure including a rear slope;

Characteristically, the light receiving portion comprises:

A plurality of cave-type light emitting diodes (LEDs) are arranged parallel to each other in the direction of the optical axis from the incident plane to the back surface slope in order to provide the optical axis directionality of the light supplied from the light source, ) Type optical guide hole;

A plurality of hollow guide tubes each having an outer surface closely fitted to the inner surface of the guide hole are integrally formed to correspond to the plurality of guide holes, and upper and lower ends are bent toward the rear body, A tube manifold coupled to the manifold;

.

Here, the guide hole may include:

Arranged in two or more columns in the upper and lower rows;

At this time, the guide holes of each column are arranged alternately with each other;

Corresponding to the inclined surface, the guide holes of the lower row are longer than the guide holes of the upper row.

Preferably, the tube has a closed end shape, and the closed end of the guide hole and the tube is closed obliquely in a direction corresponding to the inclined surface. Further, preferably, the upper end of the manifold is formed by bending at an angle such that an end thereof contacts the inclined surface.

According to the light guide plate structure of the present invention, the light supplied from the light source is guided in the direction of the optical axis through the mounting tube of the guide hole formed in parallel to the optical axis direction, so that diffusion and spreading of light in the left and right direction are suppressed, It is effective. In addition, there is an effect that the light efficiency is increased over the entire light output surface, and the luminance uniformity is thereby prevented from deteriorating.

Further, the tube functions to support the shape of the guide hole. In the present invention, a manifold having a plurality of tubes integrally formed therein is applied to the tube, At this time, since the upper and lower ends of the manifold are fitted to the thickness of the light receiving portion, there is an effect that the fastening is easy and firm.

1 is a perspective view showing a conventional light guide plate structure.
Fig. 2 is a view showing an example of the shape of the light receiving portion of Fig. 1;
3 is a perspective view illustrating a structure of a light guide plate according to an embodiment of the present invention.
4 is an enlarged partial sectional view of Fig.
Figure 5 is a plan view of Figure 3;
6 is a perspective view illustrating a structure of a light guide plate according to another embodiment of the present invention.
FIG. 7 is an enlarged partial sectional view of FIG. 6; FIG.
8 is a cross-sectional view of the tube manifold applied to Fig.

The features and effects of the present invention "backlight structure for backlight" (hereinafter referred to as "light guide structure") described or not described above will become more apparent from the following description of each embodiment with reference to the accompanying drawings. 3, the light guide plate structure of the present invention is indicated by reference numeral 10.

3 to 5, the light guide plate structure 10 of the present invention includes a planar light guide plate main body 11 having a uniform thickness, and a light guide plate 10 having a light guide plate 11, Shaped light receiving portion 12 formed to have a thickness larger than that of the main body 11 in order to allow the light to pass therethrough. The light receiving unit 12 includes a front light incidence surface 13 and a rear inclined surface 14 formed at an upper end of the incident surface 13 and inclined toward the upper surface of the light guide plate main body 11.

Naturally, the upper surface of the main body 11 is formed by the light emitted from the light source L and entering and diffusing into the main body 11 through the incident surface 13 of the light receiving portion 12, 15). At this time, a light pattern 16 is formed on the exit surface 15 in order to improve brightness and directivity of output light. More specifically, the light pattern 16 is a plurality of convex lenticular patterns extending in the direction of the optical axis X and arranged in parallel.

However, the shape of the main body 11, the light receiving portion 12, the light pattern 16, and the like in the light guide plate structure 10 of the present invention is a technique that is commonly applied to a general light guide plate structure, and is not unique to the present invention. According to the design, the light guide plate structure 10 is a conventional multi-layer structure method for molding the light receiving portion 12 and the optical pattern 16 using a UV resin on an engineering plastic material base film such as PC, PMMA, . In addition, a directional reflection pattern may be formed on the lower surface of the film, and a roll-stamping method such as a pressure forming method is generally applied for the pattern. However, the present invention is not limited to such molding and molding methods, and various other methods may be applied without limitation.

The light receiving portion 12 of the present invention is characterized in that the light receiving portion 12 of the present invention is arranged so as to extend from the incident plane 13 of the vertical planar shape toward the rear slope face 14 in order to provide an improved optical axis And a hollow cave-shaped light guide groove 17 formed in parallel and arranged in parallel to the optical axis X in the direction of the optical axis X and having a closed inner end 18, 17 is fitted with a light guide tube 19 fitted therein.

More specifically, the guide holes 17 are arranged in a horizontal line over the upper and lower two rows 17a and 17b. In order to make the intervals between the columns 17a and 17b close to each other, 17 are arranged to be alternated with each other as shown. In order to sufficiently utilize the width of the light receiving portion 12 in forming the guide hole 17, the guide hole 17 of the lower row 17b is formed in the guide hole 17a of the upper row 17a, (17).

In this structure, light supplied from the light source L to the incident surface 13 is guided by the guide hole 17 and travels in the direction of the optical axis X. At this time, considerable light amount rapidly advances into the hollow guide hole 17 (see arrows 1 and 2 in FIG. 5), and light entering the adjacent plane is also guided between the plurality of guide holes 17, (See arrow 3 in Fig. 5). Therefore, light leakage in the left and right directions as a whole can be prevented as a whole. As described below, the guide tube 19 is inserted into the guide hole 17, but the light effect is not changed.

Preferably, the guide hole 17 has its end 18 inclined in a direction corresponding to the inclined surface 14. This type of tip 18 is effective for allowing light from the light source L to enter the interior of the main body 11 naturally and quickly as in the case of the inclined surface 14 of the light receiving portion 12. [

The diameter of the light guide hole 17 in the longitudinal direction may not be constant or clogging may occur in a certain section depending on the physical properties of the light receiving part 12. In this case, in fact, refraction of incident light and advancing light becomes severe, and it becomes impossible to obtain a desired degree of directivity in the optical axis (X) direction. Therefore, measures for maintaining and supporting the shape of the guide hole 17 are required.

In the present invention, the light receiving unit 12 further includes a hollow hollow guide tube 19 mounted inside the guide hole 17 and having its outer surface closely contacted with the inner wall of the guide hole 17. The tube 19 supports the shape of the guide hole 17 so as to prevent the light from being changed due to the change in the shape of the hole 17. In addition, the interface 20 between the guide hole 17 and the light receiving portion 12 is provided so that, for example, the light entering the plane of the incident surface 13 functions to improve the directivity in the direction of arrow ③ in FIG.

Here, the guide tube 19 has a closed end 21, and preferably, the closed end 21 of the tube 19 is inclined in a direction corresponding to the inclined surface 14. This is effective for allowing the light of the light source L to enter the interior of the main body 11 naturally and quickly, similarly to the guide hole 17. However, if each of the tubes 19 is inserted into the guide hole 17 one by one, there is a problem such as ease of assembly, productivity, and continuity.

Therefore, in the present invention, a plurality of tubes 19 are provided to constitute the tube manifold 22 so as to integrally correspond to the plurality of guide holes 17. [ Specifically, the tube manifold 22 is provided with a plurality of hollow light guide tubes 19 to which the outer surface of the tube manifold 22 is closely fitted and attached to the inner surface of the guide hole 17, And the guide holes 17 are integrally formed. The upper end 23 and the lower end 24 of the manifold 22 are bent toward the rear body 11 and are pressed and coupled to the upper and lower surfaces of the light receiving portion 12, Can be firmly held.

6 to 8, the upper end 23 of the manifold 22 is formed by bending at an angle such that the end portion 25 of the manifold 22 contacts the inclined surface 14. As shown in FIG. As a result, the fastened state of the light receiving portion 12 of the manifold 22 can be more firmly maintained. The fastened state of the manifold 22 shown in Figs. 4 and 7 can be more preferably applied for the solid-state coupling of each layer structure and the manifold 22 when the applied light guide plate itself has a multilayer structure as described above There will be.

10. Light guide structure
11. Body
12. Photoreceptor
13. Incident surface
14. Slope
15. Outgoing surface
16. Light pattern
17. Guide hole
17a. Flush
17b. Lower
18. End
19. Guide tube
20. Interface
21. End
22. Manifold
23. Top
24. bottom
25. End
L. Light source
X. Optical axis

Claims (7)

And a wedge-shaped light receiving section 12 formed on the light source side of the main body 11 to have a thickness larger than that of the main body 11. The light receiving section 12 is formed of a light- A light guiding plate structure including a surface 13 and a rear sloped surface 14 inclined toward an upper surface of the light guiding plate 11 at an upper end of the incident surface 13,
The light receiving unit 12 includes:
(X) direction from the incident surface (13) to the back surface inclined surface (14) in order to provide an optical axis (X) directionality of the light supplied from the light source, A hollow cave-shaped light guide hole 17 in which each inner end 18 is closed; And
A plurality of hollow guide tubes 19 are integrally formed on the inner surface of the guide hole 17 so as to be integrally supported by the plurality of guide holes 17. The upper end 23 and the lower end 24 A tube manifold 22 bent toward the rear body 11 and compressed and coupled to upper and lower surfaces of the light receiving portion 12, respectively;
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The light guide plate structure having a tube manifold characterized by:
The method according to claim 1,
Wherein the guide holes are arranged in two rows or more in the longitudinal direction and the guide holes of the columns are arranged alternating with each other. .
3. The method of claim 2,
Wherein a guide hole (17) of the lower row (17b) is formed to be longer than a guide hole (17) of the heat ray (17b).
The method according to claim 1,
Wherein the guide hole (17) has an end (18) inclined in a direction corresponding to the inclined surface (14).
The method according to claim 1,
Wherein the tube (19) has a closed end (21).
6. The method of claim 5,
Wherein the clipped ends (18, 21) of the guide hole (17) and the tube (19) are obliquely finished in a direction corresponding to the inclined surface (14).
The method according to claim 1,
Wherein an upper end (23) of the manifold (22) is formed by bending an end portion (25) of the manifold (22) at an angle to contact the inclined surface (14).

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