KR20140078131A - Illuminance Device using Complex Optical sheet - Google Patents

Abstract

The present invention relates to a lighting device using a double optical sheet. The lighting device comprises: a light source; a reflective sheet to waveguide light irradiated from the light source to a light facing part from a light entry part; a first optical sheet which is located at a light exit part facing to the reflective sheet, and includes a first base layer and a first pattern layer formed on the upper part of the first base layer; and a second optical sheet which is formed on the first pattern layer of the first optical sheet, and includes a second base layer and a second pattern layer formed on the upper part of the second base layer. According to the present invention, the lighting device includes the double optical sheet having the pattern layers formed on the light exit part, thereby improving light condensing power, maintaining uniformity of an optical speed, solving visible displeasure and an amblyopia problem due to glare of lighting, and minimizing a reduce of optical speed efficiency.

Description

TECHNICAL FIELD [0001] The present invention relates to an illuminating device using a double optical sheet,

The present invention relates to a lighting apparatus, and more particularly, to a lighting apparatus which includes a double optical sheet having a pattern layer formed on a light emitting portion side to maintain the uniformity of the luminous flux while improving the light collecting power to improve the glare phenomenon, And a lighting apparatus using the dual optical sheet minimized.

In general, due to popularization of LED devices, LEDs are increasingly used as a light source for a TV, a monitor, a mobile display, a tablet PC, and the like (hereinafter referred to as 'display').

These LEDs have advantages such as high brightness, long life, high color reproducibility and power consumption compared to conventional CCFL (Cold Cathode Fluorescent Lamp) lighting, and they are gradually becoming the light source of the backlight unit of the display system, And the use thereof is expanding.

In particular, LED has been spotlighted as a new light source with low energy efficiency due to recent breakthroughs. In recent years, the application fields of LEDs have been increasing not only in office side lighting but also in general public areas and outdoor space billboards.

However, since the LED is generally a point light source, it is difficult to maintain the uniformity even if the display of the backlight unit is large or small. In accordance with the demand for thinning of the display, miniaturization of the LED package, The thinning of the light guide plate and the design and manufacture of an efficient light emission pattern are important techniques.

On the other hand, in 1987, the CIE technical committee reviewed the influence of consumer's eyes on the sparkle of light, the unpleasant glare, in the clause 3-31 (CIE Technical committee 3-31) and stipulated specific provisions.

This discomfort glare has been proven to have a significant impact on consumers with whitish blue eyes, such as Europe, North America, South America, and Australia.

Therefore, the CIE technical committee defined the following formula (1) as a practical glare evaluation system based on general parameters for uncomfortable glare of illumination.

L _b : luminance of the background (general background luminance)

L _s : Luminance of glare source (cd / m ² )

ω: Solid angle subtended by glare source of the light source in the observer's line of sight

P: Guth position index of each light source

Size of solid angle = ω = A _P / R ²

A _P : Area of light emitting part

R: Distance from the observer to the center of the luminaire emission area

Glare rating UGR Imperceptible 10 Perceptible 16 Just Acceptable 19 Unacceptable 22 Just Uncomfortable 25 Uncomfortable 28 Just Intolerable 31

The Glare class for the UGR value calculated using the above equation (1) is shown, and when the UGR value is 19 or less, the user does not have an uncomfortable glare.

For the above-mentioned CIE standard values, the lighting industry, the display industry, and the research field according to the use of the LED have a great interest in the implementation method in the LED lighting system that satisfies the proper UGR value without decreasing the luminous flux efficiency.

Therefore, it is very important to design and manufacture a light guide plate for an efficient light emission pattern for maintaining the uniformity while satisfying the proper UGR value without reducing the luminous flux efficiency when the LED is used as the light source of the backlight unit or when it is used as illumination Research.

In general, since the LED shows the shape of a point light source when viewed from a surface light source, a diffusing plate and a light guide plate are used to diffuse the light again into a planar light source showing uniform light. However, So that a pattern layer having a circular pattern or a polygonal pattern is formed on the base layer of the optical film or a bead is formed to give a light converging and diffusing function.

As a technique for maintaining the uniformity of the LED light source, there is a technique for a light collecting plate and an illumination system using the same, which is disclosed in Korean Patent Application Publication No. 10-2012-0067769.

The above-described technique includes at least one light source, a diffusion plate for diffusing the light emitted from the light source, and a light condensing plate for condensing the light diffused through the diffusion plate to emit light, And a microlens array formed on both sides or one surface of the light collecting plate so as to be convex to adjust the emission path of the light.

However, the above-mentioned conventional technique uses a light collecting plate formed with a diffusion plate and a microlens array, so that the light collecting power and the shielding power (a phenomenon in which the light source inside the lighting apparatus is visible and the screen uniformity is lowered) The diffusion plate and the light condensing plate are sagged downward due to the heat or the load of the LED, so that the light collecting power and the shielding power are further lowered and the durability of the lighting equipment itself is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a dual optical sheet in which a pattern layer is formed on the side of a light emitting portion to improve uniformity of luminous flux while improving light collecting power to improve a glare phenomenon, And an illumination device using the dual optical sheet.

A first base layer disposed in a light emitting portion facing the reflection sheet, the first base layer, and the second base layer; and a light- A first optical sheet made of a first patterned layer formed on the first base layer and a second patterned layer formed on the first patterned layer of the first optical sheet and having a second base layer and a second base layer formed on the second base layer, And a second optical sheet made of a patterned layer. The present invention is directed to a lighting device using a dual optical sheet.

It is preferable that the light source is an LED, and it is more preferable to provide a light source of a photometric type disposed on both sides of the rear portion of the light emitting portion.

" 형태로 형성되어 출광부 쪽으로 광의 효율적인 반사가 이루어지도록 하는 것이다.Here, the reflective sheet is disposed between the light sources toward the rear side of the light source,

So that the light can be efficiently reflected toward the light emitting portion.

It is preferable that the first pattern layer of the first optical sheet is formed of a circular cell pattern or a hexagonal cell pattern or a circular cell merge pattern or a hexagonal cell merge pattern in which some of the cells are partially merged, Are preferably formed to be 1 to 5 占 퐉 higher than the circular cell patterns or the hexagonal cell patterns.

It is preferable that the cell merging pattern is formed by merging two to five circular cell patterns or two to five hexagonal cell patterns and the density of the cell merging pattern is about 100 It is preferable that 1 to 50 cell merging patterns are formed.

Here, it is preferable that the second pattern layer of the second optical sheet is formed as a circular cell pattern or a hexagonal cell pattern.

The refractive index of the first pattern layer and the second pattern layer is preferably 1.46 to 1.48.

It is preferable that the first base layer is a PET film having a thickness of 150 to 300 占 퐉 and the second base layer of the second optical sheet is formed of any one of polystyrene, PMMA, and PC, The thickness is preferably 1.0 to 1.8 mm.

According to the above-mentioned object, the present invention provides a lighting apparatus comprising a double optical sheet having a pattern layer formed on a light-emitting portion side to maintain the uniformity of the light flux while improving the light-converging power, It solves the problems of visual discomfort and low vision, and has the effect of minimizing the reduction of luminous flux efficiency.

Further, by forming a double optical sheet composed of the first optical sheet and the second optical sheet, an air space portion is formed therebetween to further enhance the light converging effect due to the difference in refractive index between the air and the first pattern layer, and the uncomfortable glare Reduction in numerical value).

1 is a schematic view of a main part of a lighting device using a dual optical sheet according to the present invention;
2 is a schematic view of a first optical sheet and a second optical sheet having a first pattern layer provided with a circular cell merging pattern according to an embodiment of the present invention;
FIG. 3 is a photograph showing a first pattern layer having a circular cell merge pattern of FIG. 2; FIG.
FIG. 4 is a diagram illustrating an appearance of an LED lighting device manufactured according to an embodiment of the present invention; FIG.
5 is a diagram showing a light distribution diagram for an LED illumination device manufactured according to an embodiment of the present invention;
FIG. 6 is a side view of a second optical sheet manufactured according to an embodiment of the present invention; FIG.
Fig. 7 is a diagram showing a light condensing simulation by a cross-sectional shape of a second optical sheet and a pattern of a second pattern layer manufactured according to an embodiment of the present invention; Fig.

The present invention provides a double optical sheet having a pattern layer formed on the light-exiting portion side when the LED is used as a light source of a backlight unit of a display or when an LED is used as a light source in a lighting fixture, To a lighting apparatus using a dual optical sheet which maintains uniformity, solves problems of visual discomfort and visual deterioration caused by illumination glare, and minimizes reduction of luminous flux efficiency.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of a main part of a lighting apparatus using a dual optical sheet according to the present invention; FIG.

As shown in the drawing, the illumination device using the dual optical sheet according to the present invention includes a light source 100, a reflection sheet 200 for guiding the light emitted from the light source 100 to the light- A first optical sheet 300 located at a light emitting portion facing the first optical sheet 200 and including a first base layer 310 and a first pattern layer 320 formed on the first base layer 310, The first optical sheet 300 is formed on the first pattern layer 320 of the first optical sheet 300 and includes a second base layer 410 and a second pattern layer 420 formed on the second base layer 410, The optical sheet 400 is formed largely, and the optical sheet is double formed on the light emitting portion side to improve the uniformity of the light flux.

First, the light source 100 according to the present invention will be described.

The light source 100 according to the present invention preferably uses an LED, and is disposed on the rear side of the light emitting unit so that light is guided toward the light emitting unit.

Specifically, the LED light source 100 is disposed behind the light emitting unit, particularly on both sides of the rear side of the light emitting unit, and realizes a metering type backlight unit or a lighting device. The metering type backlight unit or the lighting device is advantageous in that the light source 100 is positioned on the side surface with respect to the light emitting unit and is less glare than the direct light type and a hot spot that is visually recognized directly from the LED light source is less visible .

The reflection sheet 200 guides the light emitted from the light source 100 from the light-incident portion to the light-receiving portion. The reflection sheet 200 is formed at a predetermined distance from the light source 100, So that spawning can take place.

Here, the LGP (Light Guide Pannel) may be applied to the reflective sheet and the reflective sheet may be formed on the LGP backplane in the case of the LED side illumination method.

" 형태로 형성되는 것이 바람직하다.The reflective sheet 200 is positioned between the light sources 100 toward the rear of the light source 100,

Quot; < / RTI >

The light source 100 is positioned on both sides of the reflective sheet 200 having the shape as described above so that the light of the incident light source 100 is reflected toward the center of the light emitting unit 100 on both sides of the reflective sheet 200 having a relatively large radius of curvature, And the light of the incident light source 100 is reflected toward the front side at the center side having a small radius of curvature so that the light source 100 can have a direct type effect even though it is a side light measuring type.

The first optical sheet 300 is located at a light emitting portion facing the reflective sheet 200 and includes a first base layer 310 and a first pattern 310 formed on the first base layer 310, Layer 320 as shown in FIG.

Here, the first pattern layer 320 may be a circular cell pattern, a hexagonal cell pattern, or a smoothed hexagonal cell pattern in which the rim of the hexagonal shape is smoothed. That is, circular, hexagonal, or smoothed hexagonal patterns are arranged in the upper layer of the first base layer 310, the height of the cell is about 10 to 40 μm, and the width of the cell is about 20 to 80 μm. Here, the beam angle can be adjusted by applying various patterns such as changing the height of the cell and the width of the cell.

The circular cell pattern or the hexagonal cell pattern is formed by a laminating and curing process with a master mold made by an imprinting process or an exposure patterning process by a mask in which a cell pattern is formed.

In addition, the first pattern layer 320 may be a pattern in which a part of the circular cell pattern or the hexagonal cell pattern is combined to form a circular cell pattern or hexagonal cell pattern independent of the circular cell merging pattern or the hexagonal cell merging pattern .

In the circular cell merging pattern and the hexagonal cell merging pattern, a master mold having a cell merging pattern formed using a mask having a circular or hexagonal cell merging pattern is formed, an imprint resin layer is formed on the base mold, The first pattern layer 320 having the cell merging pattern is formed.

This is because the final cell merging pattern is formed with a positive angle, so that the pattern of the master mold must be formed at an obtuse angle, so that the light receiving part (excluding the cell merge pattern and the cell pattern) And a pattern mask in which a cell merging pattern and a cell pattern portion are opaque on a transparent substrate is used in response to the negative photoresist.

Here, in the cell merging pattern mask, the cell merging pattern is formed by connecting the line width portions of the existing circular or hexagonal cell patterns with the line width portions of the neighboring cell patterns and by patterning them so that two cells of the cell pattern are connected Respectively.

In the hexagonal cell merging pattern mask, the amount of the radiation transmitted through the cell merging pattern region is less than that of the independent cell pattern region, (More photoresist layer is removed) than the independent cell pattern region.

Therefore, the cell merging pattern of the pattern layer having the final cell merging pattern is formed higher than the independent cell pattern.

Specifically, the circular cell merging pattern or the hexagonal cell merging pattern forms a relief pattern having a height of 1 to 5 占 퐉 higher than that of the independent circular cell pattern or the hexagonal cell pattern.

In addition, the cell merging pattern is formed by merging two or more circular cell patterns or hexagonal cell patterns. At least two or more independent hexagonal cell patterns must be merged. If more than five cells are merged, The adhesion area with the sheet 400 is increased to reduce the luminance and the density of the pattern. Therefore, it is preferable that five or less hexagonal cells are formed by merging.

The density of the cell merging pattern is preferably 1 to 50 cell merging patterns for 100 circular cell patterns or 100 hexagonal cell patterns. This is because the density of the merged cells is less than 15%, that is, 100%, when the density of the merged cells is less than 0 to 12% When about 15 hexagonal cell merging patterns are formed with respect to six hexagonal cell patterns, it is preferable to maintain the adhesive force and to reduce the loss of the luminance value.

The cell merging pattern is formed by forming the air space between the first optical sheet 300 and the second optical sheet 400 to increase the light collecting power and to increase the light collecting power of the second optical sheet 400 by the close contact between the first optical sheet 300 and the second optical sheet 400 Thereby preventing occurrence of stains. As the H / D of the first pattern layer 320 becomes smaller (the height H of the pattern and the diameter D), the mirror surface of the second base layer 420 and the pattern of the first pattern layer 320 The property to be brought into close contact becomes strong. Then, a cell merging pattern is formed with a minimum quantity to prevent wet out.

The first pattern layer 320 may be made of a transparent material such as a UV curable epoxy acrylate, a urethane acrylate, a polyester acrylate, and a substituent having a controlled refractive index. SU-6, SU- 7, and these materials generally have a refractive index of 1.46 to 1.48.

The first base layer 310 is preferably formed of a PET film. Specifically, the first base layer 310 may have a thickness of 150 to 300 탆.

The second optical sheet 400 is formed on the first pattern layer 320 of the first optical sheet 300 and includes the second base layer 410 and the second base layer 410, And a second pattern layer 420 on the upper layer. That is, a circular cell pattern or a hexagonal cell pattern of the first pattern layer 320 of the first optical sheet 300 is adhered to the second base layer 410, and the first pattern layer 320 is bonded to the cell In the case where the merging pattern is formed, since the cell merging pattern has a high height, this portion and the second base layer 410 are bonded.

Particularly, when the cell merging pattern is adhered to the second base layer 410, the contact area with the second base layer 410 is minimized, and the contact area between the first optical sheet 300 and the second optical sheet 400 The air space portion of the gap is formed to improve the light collection efficiency of the light without reducing the light efficiency. This will be described in detail later.

Here, the second pattern layer 420 is formed in a circular cell pattern, a hexagonal cell pattern, or a smoothing hexagonal cell pattern in which the rim of the hexagonal shape is smoothed. That is, circular, hexagonal or smoothed hexagonal patterns are arranged on the second base layer 410.

The circular cell pattern or the hexagonal cell pattern is formed by a laminating and curing process with a master mold made by an imprinting process or an exposure patterning process by a mask in which a cell pattern is formed.

The second base layer 410 is formed of one of polystyrene, PMMA, and PC. The second base layer 410 is formed of a relatively hard material as compared with the first base layer 310, And more preferably 1.0 to 1.8 mm.

That is, the first base layer 310 is formed of PET material in consideration of circularity, workability, and the like. Since the second base layer 410 is formed of a material that is harder than the first base layer 310, The material of the second base layer 410, which is formed of a material such as inexpensive polystyrene, PMMA, and PC, and which is positioned on the outer side or the lower side of the lighting equipment, is made of a harder and more rigid material, 310) is prevented from crying, and the internal lighting equipment is held so as not to fall down, thereby protecting the product.

Here, a material having a refractive index of 1.46 to 1.48, which is similar to the refractive index of the first pattern layer 320, is used as the second pattern layer 420, and basically the same material is used.

2 is a schematic view of a first optical sheet 300 and a second optical sheet 400 having a first pattern layer 320 having a circular cell merging pattern 321 according to an embodiment of the present invention. The cell merging pattern 321 is formed to be higher with respect to the other independent cell patterns to minimize the area of adhesion with the second base layer 410 to minimize the reduction of the light flux and to form the air space portion, .

FIG. 3 is a photograph of the first pattern layer 320 having the circular cell merging pattern 321 of FIG. 2. The size of each circular cell pattern is 23 .mu.m, the height is 10 .mu.m, The height of the first base layer 310 is 11.8 占 퐉, and the thickness of the PET as the first base layer 310 is 188 占 퐉.

4 shows that the first optical sheet 300 of FIG. 2 and the second base layer 410 of the second optical sheet 400 have a polystyrene thickness of 1.5 mm and the second pattern layer 420 of the second optical sheet 400 The diameter of the circular cell pattern was 23 mu m, the height was 10 mu m, and the material of the pattern layer was SU-6). It was confirmed that the uniformity of the luminous flux was improved.

FIG. 5 is a graph showing the distribution of light distribution for an LED illumination device manufactured according to an embodiment of the present invention. In the case of a general diffusion plate, the diffusing angle is wider, and compared with the case of using only the second optical sheet, And the second optical sheet, it was confirmed that the light distribution distribution was narrowed.

The diffraction angle can be controlled by controlling the height or the diameter of the pattern of the pattern layers of the first base layer and the second base layer.

FIG. 6 is a side view of a second optical sheet manufactured according to an embodiment of the present invention, wherein a diameter of a pattern is 23 μm and a height is 10 μm.

7 is a diagram showing a light condensing simulation by the cross-sectional shape of the second optical sheet and the pattern of the second pattern layer manufactured according to the embodiment of the present invention. As shown in the figure, a simulation is performed in which light is incident on the side surface of the pattern and is reflected from the inside of the pattern through the refraction after the total reflection, and it is confirmed that the light-gathering power and the diffraction angle are excellent by the pattern of the lens shape.

Depending on the embodiment, the entire effective light emitting surface 480x480, flux 3236lm, color temperature 3600K, L65 ° luminance 2047Cd / mm ^2, oriented for each 72 °, the transverse direction (crosswise) to the UGR value is 16.3, a longitudinal direction (endwise ), The UGR value is 17.7 and the UGR value is 19 or less, indicating that the user does not have any uncomfortable glare.

By forming the double optical sheet composed of the first optical sheet and the second optical sheet as described above, the first base layer, the first pattern layer, and the second base layer of the second optical sheet, And the second pattern layer. Thus, an air space is formed between the first optical sheet and the second optical sheet to increase the condensing effect due to the difference in refractive index between the air and the first pattern layer, and the uncomfortable glare (UGR value ) And wet out (stain caused by adhesion between the second base layer and the first pattern layer) can be improved.

A material such as PET used as the first base layer of the first optical sheet has a refractive index of about 1.57 and a material such as polystyrene (PS) used as the second base layer of the second optical sheet has a refractive index of about 1.54, The refractive index of air is 1, and the refractive indices of the first pattern layer and the second pattern layer are 1.46 to 1.48.

As described above, the light reflected from the light source through the reflective sheet sequentially passes through the first base layer, the first pattern layer, the air space portion, the second base layer, and the second pattern layer on the light- The diffusing effect and the light converging effect due to the difference in refractive index between the first and second pattern layers, the first pattern layer and the first pattern layer and the air space portion, the air space portion and the second substrate layer, .

INDUSTRIAL APPLICABILITY The present invention is applicable to a backlight unit or a lighting device using an illumination device, in particular, an LED, and is likely to be used in a lighting device for raising the uniformity of luminous flux and the condensing effect.

100: light source 200: reflective sheet
300: first optical sheet 310: first substrate layer
320: first pattern layer 321: cell merging pattern
400: second optical sheet 410: second substrate layer
420: second pattern layer

Claims (16)

Light source;
A reflective sheet for guiding light emitted from the light source to the light-shielding portion from the light-incoming portion;
A first optical sheet positioned at a light emitting portion facing the reflective sheet, the first optical sheet being composed of a first base layer and a first pattern layer formed on the first base layer; And
And a second optical sheet formed on the first pattern layer of the first optical sheet and including a second base layer and a second pattern layer formed on the second base layer, Lighting device using optical sheet. The light source according to claim 1,
Wherein the light source is a light emitting diode (LED). The light source according to claim 1,
And the light emitting portion is located on both side surfaces of the rear portion of the light emitting portion. The reflective sheet according to claim 3,
Located between the light sources toward the rear side of the light source,

"≪ / RTI > wherein the first optical sheet is formed in the form of a sheet. The optical sheet according to claim 1, wherein the first pattern layer of the first optical sheet comprises:
Wherein the light guide plate is formed of a circular cell pattern or a hexagonal cell pattern. 6. The optical sheet according to claim 5, wherein the first pattern layer of the first optical sheet
Wherein a part of the circular cell pattern or the hexagonal cell pattern is combined to provide a circular cell merging pattern or a hexagonal cell merging pattern. The method of claim 6, wherein the circular cell merging pattern or the hexagonal cell merging pattern comprises:
Wherein the light source is formed to have a height of 1 to 5 占 퐉 higher than that of an independent circular cell pattern or a hexagonal cell pattern. 7. The method of claim 6,
Wherein two to five circular cell patterns or two to five hexagonal cell patterns are combined and formed. 7. The method according to claim 6, wherein the density of the cell-
Wherein 1 to 50 cell merging patterns are formed for 100 circular cell patterns or 100 hexagonal cell patterns. The method as claimed in claim 1, wherein the refractive index of the first pattern layer
1.46 to 1.48. ≪ RTI ID = 0.0 > 11. < / RTI > The method according to claim 1,
Wherein the second optical sheet is formed of a PET film. The optical sheet according to claim 11, wherein the thickness of the first base layer of the first optical sheet
150 to 300 占 퐉. The optical sheet according to claim 1, wherein the second pattern layer of the second optical sheet comprises:
Wherein the light guide plate is formed of a circular cell pattern or a hexagonal cell pattern. The optical sheet according to claim 1, wherein the second base layer of the second optical sheet
Polystyrene, PMMA, and PC. ≪ RTI ID = 0.0 > 21. < / RTI > The method according to claim 1, wherein the thickness of the second base layer
Wherein the thickness of the first optical sheet is 1.0 to 1.8 mm. The method as claimed in claim 1, wherein the refractive index of the second pattern layer
1.46 to 1.48. ≪ RTI ID = 0.0 > 11. < / RTI >

Images