KR20160136258A - Linear light source and back light unit including the same - Google Patents

Abstract

The present invention relates to a linear light source and to a backlight unit including the same. The present invention includes an optical distributor having a light guiding unit and an optical extracting unit, and a light source formed on one side and both sides of the optical distributor. The present invention can optimize power efficiency by using one or two light sources.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a linear light source and a backlight unit including the linear light source,

The present invention relates to a linear light source and a backlight unit including the linear light source.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LCD backlight unit (BLU) for use in a conventional smart phone, which comprises a LED lamp array as a light source, a light guide plate for distributing light emitted from the LED lamp to a width corresponding to a screen, (Diffusing sheet, prism sheet, and protective sheet) which homogenized while changing the outgoing angle of the emitted light to vertical one was combined to constitute one BLU.

Here, the light guide plate serves to guide the light from the light source evenly to all directions, and the reflective sheet reflects the light exiting to the lower surface of the light guide plate and returns the light to the light guide plate, The sheet serves to scatter light and to uniformize the brightness of light. The prism sheet functions to improve light by refracting light by vertically, horizontally, and rightwardly, thereby improving brightness. The protective sheet is provided in a groove between prisms of a prism sheet It protects against foreign substances such as dust and acts to prevent scratches and the like.

However, in the conventional BLU, the diffusion sheet and the prism sheet are used in conjunction with each other in order to equalize the brightness and improve the light efficiency, and the diffusion sheet is provided separately from the prism sheet. As a result, there is a limit in reducing the thickness and weight of the BLU, increasing the number of assembling processes, increasing the defect rate, and increasing the raw material cost and the production cost as a whole.

In this regard, Korean Patent Publication No. 2012-0070880 discloses a backlight unit.

In the conventional mobile BLU, the LEDs are arranged in a row in a dense arrangement as possible, so that light is incident on the light guide plate. Such a structure is a light source close to a one-dimensional linear light source, so it is easy to produce a uniform brightness distribution over a large area. However, a large amount of LED light sources must be used for this purpose, so that a large amount of manufacturing cost is required for LED, substrate for mounting LED, wiring and the like.

The present application is intended to provide a backlight unit including a linear light source and the linear light source.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

According to a first aspect of the present invention, there is provided an optical distributor comprising: an optical distributor including a waveguide portion and a light extracting portion formed with a fine pattern; And a light source formed on one side or both sides of the optical splitter, wherein the light extracting unit is attached to the waveguide unit, and the interval of the fine patterns formed in the light extracting unit is dense according to the distance from the light source A linear light source.

The second aspect of the present application provides a backlight unit for a mobile, comprising a linear light source according to the first aspect of the present application, wherein the linear light source is disposed on a side surface of the light guide plate.

According to an embodiment of the present invention, light emitted from a light source disposed on one side or both sides of the optical distributor and traveling without loss by total internal reflection along the waveguide is transmitted through a fine pattern formed on a light extracting portion attached to a side surface of the waveguide portion, By emitting the light in the vertical direction to the outside of the optical distributor, light can be uniformly incident on the light guide plate of the BLU. In addition, by reducing the number of uses of the light source, it is possible to reduce the material cost, labor cost, and the like of the light source and the subassemblies. In addition, by using only one or two light sources, it is possible to optimize the power efficiency, and as the mounting space becomes smaller, the degree of freedom in designing the mechanism of the mobile device can be increased. In addition, since the fine pattern formed on the light extracting unit has a size of several micrometers, problems such as a hot spot or a cold spot which deteriorates the BLU image quality in the light source used in the past can be solved.

1 is a schematic diagram showing a linear light source according to an embodiment of the present invention.
2 is a schematic diagram illustrating the operation of a linear light source according to one embodiment of the present application.
3 is a schematic diagram showing a backlight unit for mobile according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is " on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as " including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise. The terms " about ", " substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure. The word " step (or step) " or " step " used to the extent that it is used throughout the specification does not mean " step for.

Throughout this specification, the term " combination (s) thereof " included in the expression of the machine form means a mixture or combination of one or more elements selected from the group consisting of the constituents described in the expression of the form of a marker, Quot; means at least one selected from the group consisting of the above-mentioned elements.

Throughout this specification, the description of "A and / or B" means "A or B, or A and B".

Hereinafter, embodiments and examples of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to these embodiments and examples and drawings.

According to a first aspect of the present invention, there is provided an optical distributor comprising: an optical distributor including a waveguide portion and a light extracting portion formed with a fine pattern; And a light source formed on one side or both sides of the optical splitter, wherein the light extracting unit is attached to the waveguide unit, and the interval of the fine patterns formed in the light extracting unit is dense according to the distance from the light source A linear light source.

In this regard, FIG. 1 is a schematic diagram showing a linear light source 400 according to an embodiment of the present invention.

The linear light source 400 includes an optical divider including a waveguide portion 200 and a light extracting portion 300 in which a fine pattern 310 is formed and a light source 100, The light extracting unit 300 having the fine pattern 310 may be attached to the waveguide unit 200.

In one embodiment of the present invention, the light source 100 may be located on one side or both sides of the optical distributor. As the light source 100, a point light source such as a light emitting diode (LED) may be used. In addition, a plurality of point light sources may be used, or a point light source and a means for converting the point light source into linear fluorescent light may be used together.

In one embodiment of the present invention, the waveguide unit 200 guides light incident from the light source 100 to cause surface light emission. The waveguide unit 200 may be a plastic-based one such as acryl, which is one of transparent materials capable of transmitting light But is not limited thereto. For example, the waveguide part 200 may be formed of a material selected from the group consisting of polymethylmethacrylate (PMMA), polycarbonate (PC), polyacrylate (PA), polyurethane, But are not limited to, those selected from the group consisting of combinations of < RTI ID = 0.0 > For example, when the PMMA series excellent in weatherability and coloring property is used as the waveguide part 200, it is not easily broken or deformed due to its high mechanical strength, is light and has high chemical resistance and low in absorbency against light in the visible light range, And gloss can be excellent.

In one embodiment of the present invention, the light extractor 300 having the fine pattern 310 may be formed of a transparent material capable of transmitting light. For example, the light extractor 300 may be formed of a polycarbonate series, a polysulfone series, a polyacrylate series, a polystyrene series, a polyvinylchloride series, a polyvinyl A polyvinyl alcohol series, a polynorbornene series, a polyester series, a polyurethane, a polyethyleneterephtalate, a polyethylene naphthalate, and combinations thereof. , But the present invention is not limited thereto.

In one embodiment of the present application, the fine pattern 310 includes a shape selected from the group consisting of a plurality of truncated cone shapes, pyramid shapes, prism shapes, lenticular shapes, and combinations thereof, But may not be limited thereto.

In one embodiment of the present invention, the luminance and / or viewing angle distribution of light output to the outside from the optical distributor may be determined by the area or density of the fine pattern 310 formed in the light extracting unit 300, But may not be limited thereto.

The light incident on the waveguide unit 200 through the light source 100 is emitted to the outside of the optical distributor through the fine pattern 310 formed in the light extracting unit 300. In this case, , But may not be limited thereto. The waveguide part 200 may be separated from the light source 100 by using an optical distributor having a light extracting part 300 with the fine pattern 310 formed thereon in the waveguide part 200. In this case, The light incident to the inside of the fine pattern 310 may be emitted to the outside of the optical distributor, but the present invention is not limited thereto.

In one embodiment of the present invention, the light emitted to the outside of the optical distributor may be emitted in a direction perpendicular to the optical distributor, but may not be limited thereto.

In this regard, Figure 2 is a schematic diagram illustrating the operation of a linear light source according to one embodiment of the present application.

2, the linear light source 400 according to an embodiment of the present invention may be configured such that light is incident into the optical splitter through the light source 100 disposed on a side surface of the optical splitter, Since the incident light corresponds to the total reflection condition on both the upper and lower surfaces of the waveguide unit 200, the incident light propagates in the waveguide unit 200 without loss. The light that is introduced into the fine pattern 310 formed on the light extracting unit 300 attached to the waveguide unit 200 during the process is reflected by the fine pattern 310 formed in the light extracting unit 300 And may be emitted outside the optical splitter.

The intensity of light emitted from all the positions of the linear light source 400 can be made uniform by designing the area density of the fine pattern 310 formed in the light extracting unit 300, But may not be limited thereto.

In an embodiment of the present invention, the interval of the fine patterns 310 formed in the light extracting unit 300 may be dense according to the distance from the light source 100, but may not be limited thereto. For example, the distance between the fine patterns 310 may be increased in proportion to the distance from the light source 100, and the distance between the fine patterns 310 may be shorter than the distance from the light source 100 And the distance from the light source 100 increases. Accordingly, the intensity of light emitted from all the positions of the linear light source 400 may be uniform, but the present invention is not limited thereto.

The second aspect of the present application provides a backlight unit for a mobile, comprising a linear light source according to the first aspect of the present application, wherein the linear light source is disposed on a side surface of the light guide plate.

3 is a schematic diagram showing a backlight unit for mobile according to an embodiment of the present invention.

3, the backlight unit according to an embodiment of the present invention includes a light guide plate 500 having a fine pattern 510 formed thereon, a diffusion sheet 600 disposed on the upper portion of the light guide plate 500, And a linear light source 400 disposed on a side surface of the light guide plate 500. The light guide plate 500 includes a light source 400,

In one embodiment of the present invention, the light guide plate 500 serves to guide light supplied from a light source to the liquid crystal display panel side, and the light guide plate 500 is made of acrylic, which is one of transparent materials capable of transmitting light, But it may not be limited thereto. For example, the light guide plate 500 may be formed of a material selected from the group consisting of polymethylmethacrylate (PMMA) series, polycarbonate (PC), polyacrylate (PA), polyurethane, But are not limited to, those selected from the group consisting of combinations. For example, when a light guide plate of PMMA series excellent in weatherability and colorability is used, it has high mechanical strength, is not easily broken or deformed, is light, has high chemical resistance, and has low transparency and gloss due to low light absorbency in visible light range . For example, when an olefin-based transparent resin having a specific gravity of about 1 is used, the light weight of the mobile backlight unit according to the present invention can be realized.

In one embodiment of the present invention, the light extracting unit 300 of the linear light source 400 may be disposed on the side surface of the light guide plate 500, but the present invention is not limited thereto. The light incident into the waveguide portion 200 of the linear light source 400 in the light source 100 of the linear light source 400 may be incident on the light extracting portion 300 of the linear light source 400 The light may be emitted to the outside of the optical distributor of the linear light source 400 through the fine pattern 310 formed on the light source 400. In one embodiment of the present invention, by arranging the light extracting unit 300 of the linear light source 400 on the side surface of the light guide plate 500, the light emitted to the outside of the light distributor is transmitted to the light extracting unit 300 The light may be emitted in a direction perpendicular to the optical distributor through the fine pattern 310 formed on the light guide plate 500 and incident into the light guide plate 500. However, the present invention is not limited thereto.

In one embodiment of the present invention, the linear light source 400 may be attached to the side surface of the light guide plate 500, but the present invention is not limited thereto. In an exemplary embodiment of the present invention, an air layer may exist between the linear light source 400 and the light guide plate 500. In order to achieve better light utilization efficiency, the air layer may be omitted, But may be, but not limited to, attaching a linear light source 400.

In one embodiment of the present invention, attaching the linear light source 400 to the side surface of the light guide plate 500 may be performed by a transparent adhesive, but the present invention is not limited thereto. In one embodiment of the present invention, the transparent adhesive may have the same or similar optical refractive index as the material of the linear light source or the light guide plate. For example, the transparent adhesive may include, but not limited to, a pressure sensitive adhesive, an optical transparent adhesive, a UV tape, an acrylic ultraviolet curing base, and combinations thereof.

In one embodiment of the present invention, the light guide plate 500 may include, but is not limited to, a light guide plate having a pattern formed therein. In one embodiment of the present invention, the pattern 510 formed on the light guide plate on which the pattern is formed includes a shape selected from the group consisting of truncated pyramids, pyramids, cylinders, and combinations thereof, But may not be limited thereto.

In one embodiment of the present invention, the mobile backlight unit includes light incident into the light guide plate 500 through the light extracting unit 300 of the linear light source 400, The total reflection condition is satisfied on both the upper and lower surfaces of the light guide plate 500, so that the light guide plate 500 advances inside the light guide plate 500 with almost no loss. The light incident on the pattern 510 formed on the light guide plate 500 on which the pattern 510 is formed may be emitted to the outside of the light guide plate 500 without reflection and emit light as it is.

In one embodiment of the present invention, the light emitted to the outside of the light guide plate 500 is scattered by the diffusion sheet 600, so that the brightness of light can be made uniform. In addition, light emitted to the back surface of the light guide plate 500 may be re-incident into the light guide plate 500 by the reflective sheet 700. As described above, the reflective sheet 700 reduces light loss by re-entering the outside of the mobile backlight unit according to one embodiment of the present invention and transmits the light to the upper surface of the light guide plate 500 The uniformity of the light can be improved.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

100: Light source
200: waveguide part
300: light extracting unit
310: fine pattern
400: linear light source
500: light guide plate
510: pattern
600: diffusion sheet
700: reflective sheet

Claims (8)

An optical splitter including a waveguide portion, and a light extracting portion formed with a fine pattern; And
A light source formed on one side or both sides of the optical distributor;
/ RTI >
The light extracting unit is attached to the waveguide unit,
The spacing of the fine patterns formed in the light extracting unit is dense according to the distance from the light source,
Wherein light incident on the waveguide section through the light source is emitted to the outside of the optical distributor through the light extracting section,
Wherein light emitted to the outside of the optical splitter is emitted in a direction perpendicular to the optical splitter,
Since the light incident on the waveguide portion corresponds to the total reflection condition on both the upper and lower surfaces of the waveguide portion, the light travels in the waveguide portion without loss,
Wherein the fine pattern is formed in a normal shape in the light extracting portion and attached to the waveguide portion in a reversed phase.
Linear light source.
The method according to claim 1,
Wherein the fine pattern comprises a shape selected from the group consisting of a plurality of truncated, pyramidal, prismatic, lenticular, and combinations thereof, and their inverse phases.
A linear light source according to claim 1 or 2,
Wherein the linear light source is disposed on a side surface of the light guide plate.
Backlight unit for mobile.
The method of claim 3,
And attaching the linear light source to the side surface of the light guide plate.
5. The method of claim 4,
Wherein attaching the linear light source to the side surface of the light guide plate is performed by a transparent adhesive.
The method of claim 3,
Wherein the light guide plate includes a light guide plate having a pattern formed thereon.
The method according to claim 6,
Wherein the pattern formed on the light guide plate in which the pattern is formed includes a shape selected from the group consisting of truncated cones, pyramids, cylinders, and combinations thereof, and reversed phases thereof.
The method of claim 3,
Wherein light is incident on the light guide plate through a light extracting unit of the linear light source.

Images