WO2020162678A1

WO2020162678A1 - Optical film for mini led or micro led backlight unit

Info

Publication number: WO2020162678A1
Application number: PCT/KR2020/001575
Authority: WO
Inventors: 김진환; 조성식; 김영만; 강동환
Original assignee: 주식회사 엘엠에스
Priority date: 2019-02-07
Filing date: 2020-02-03
Publication date: 2020-08-13
Also published as: KR102185708B1; KR20200097122A

Abstract

An optical film that transmits light emitted from a mini light emitting diode (LED) or a micro LED, according to various embodiments of the present invention, may comprise: a first base film; and a reflective pattern layer disposed on one side of the first base film. Here, the reflective pattern layer may comprise a plurality of holes arranged to correspond to the position of the mini LED or the position of the micro LED so as to transmit light emitted from the mini LED or the micro LED.

Description

Optical film for mini LED or micro LED backlight unit

The present invention relates to an optical film for a mini LED or micro LED backlight unit, and more particularly, to an optical film that transmits mini LED light or micro LED light and reflects the transmitted light to minimize luminance loss.

With the progress of research on light emitting diodes (LEDs), the light energy conversion efficiency of LEDs increases, and LEDs are rapidly replacing conventional light emitting devices.

LEDs currently being developed have advantages such as miniaturization, weight reduction, and low power consumption. Accordingly, LEDs are actively used as light sources of various image display devices.

The size of the LED chip is gradually becoming smaller. Examples of tiny LED chips are mini LEDs and micro LEDs. In general, a chip size of a mini LED may be defined as 100 μm to 200 μm, and a chip size of a micro LED may be defined as 5 μm to 100 μm. In the case of mini LED or micro LED, since each LED chip becomes a pixel or light source individually, restrictions on the size and shape of the display are resolved, and a clearer picture quality can be realized than when using a conventional light source.

In addition to miniaturization of the LED chip size, research on optical films to complement the LED optical characteristics is also active.

The present invention provides an optical film that minimizes luminance loss by reflecting light emitted from a mini LED or micro LED.

The present invention provides an optical film capable of adjusting light distribution through local dimming of a mini LED or a micro LED.

An optical film that transmits light emitted from a mini LED or micro LED according to various embodiments of the present disclosure may include a first base film and a reflective pattern layer disposed on one side of the first base film. Here, the reflective pattern layer may include a plurality of holes disposed to correspond to the location of the mini LED or the location of the micro LED so as to transmit the light emitted from the mini LED or the micro LED.

According to various embodiments of the present disclosure, the optical film may minimize luminance loss by reflecting light emitted from a mini LED or a micro LED.

According to various embodiments of the present disclosure, the optical film may enable adjustment of light distribution through local dimming of a mini LED or a micro LED.

1 is an exploded view of a liquid crystal display according to an exemplary embodiment of the present invention.

2 shows a direct-type LED light source according to an embodiment of the present invention.

3 is a cross-sectional view of an optical film according to an embodiment of the present invention.

4 illustrates a reflective pattern layer according to an embodiment of the present invention.

5 illustrates an arrangement of a plurality of holes in a reflective pattern layer according to an exemplary embodiment of the present invention.

6 illustrates an arrangement of a plurality of holes in a reflective pattern layer according to another embodiment of the present invention.

7 is a cross-sectional view of an optical film according to another embodiment of the present invention.

8 is a cross-sectional view of an optical film according to still another embodiment of the present invention.

9 shows a color space of the International Lighting Commission according to an embodiment of the present invention.

10 shows a spectral spectrum measurement result according to an embodiment of the present invention.

11 is a cross-sectional view of an optical film according to another embodiment of the present invention.

12 is a perspective view of an optical film according to another embodiment of the present invention.

13 is a cross-sectional view of an optical film according to still another embodiment of the present invention.

14 is a cross-sectional view of an optical film according to another embodiment of the present invention.

15 shows a result of measuring resolution of an optical film according to an embodiment of the present invention.

16 illustrates an arrangement of an optical film and a mini LED or micro LED according to an embodiment of the present invention.

17 illustrates an arrangement of an optical film and a mini LED or micro LED according to another embodiment of the present invention.

18 illustrates an arrangement of an optical film and a mini LED or micro LED according to another embodiment of the present invention.

19 shows an arrangement of an optical film and a mini LED or micro LED according to another embodiment of the present invention.

Hereinafter, the operating principle of a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, when it is determined that a detailed description of a related known function or configuration may obscure the subject matter of the present disclosure in describing an embodiment of the present invention, a detailed description thereof will be omitted. In addition, terms used in the following are terms defined in consideration of functions in the present invention, which may vary according to the intention or custom of users or operators. Therefore, the definition of the terms used should be interpreted based on the contents throughout the specification and functions corresponding thereto.

The backlight unit is a light source of a liquid crystal display (LCD). A liquid crystal display device is a device that cannot emit light by itself. Accordingly, the backlight unit including the light source irradiates light from the rear surface of the liquid crystal display toward the liquid crystal panel. Through this, an identifiable image can be implemented.

The backlight unit uses a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp, and a light emitting diode (LED) as a light source.

The backlight unit is divided into an edge type and a direct type according to the arrangement structure of the light source. The direct type can be divided and driven compared to the edge type, so that an image can be implemented more delicately than the edge type.

Hereinafter, an optical film included in the direct-type LED backlight unit will be described in detail.

Referring to FIG. 1, a liquid crystal display device (or a liquid crystal display (LCD) device) 1 includes a backlight unit 10 and a liquid crystal panel 20. In general, the backlight unit 10 may be provided at the rear of the liquid crystal panel 20 to irradiate light onto the liquid crystal panel 20. The backlight unit 10 includes a light source 11, a reflective sheet 12, a color conversion sheet 13, a diffusion lens sheet 14, a

diffusion sheet

15, 18, a

prism sheet

16, 17, and a reflective polarization sheet. (19) may be included. Here, the backlight unit 10 may not include at least one of the elements 11 to 19 included in the backlight unit 10 or may be formed by adding other elements other than the elements 11 to 19. In addition, the backlight unit 10 may be formed in various combinations including at least one of the components 11 to 19 included in the backlight unit 10.

The light source 11 provides light. For example, the light source 11 may include a plurality of LED chips that emit light. As an example, referring to FIG. 2, the LED chips 11'-1 may be arranged in a tiled manner to form a direct type 11'.

Depending on the size of the LED chip, LEDs are large LED (chip size: 1,000 µm or more), medium LED (chip size: 300-500 µm), and small LED (chip size: 200-300 μm), mini LEDs (chip size 100-200 μm), micro LEDs (chip size: 100 μm or less). Here, the LED may include a material such as InGaN or GaN.

As the chip size of the LEDs of the backlight unit decreases, the number of LEDs can be easily adjusted, so that the luminance characteristics and color uniformity of the liquid crystal display 1 can be improved and slimmed. In addition, as the chip size of the LED decreases, power consumption can be reduced, thereby reducing battery consumption of portable devices and extending the life of the battery.

Compared to conventional direct-type LEDs, when using mini LEDs or micro LEDs, the size of the LEDs is reduced, so local dimming is possible. Local dimming can improve picture quality and increase power efficiency. Here, the local dimming is a technology that controls the brightness of an LED used as a backlight based on a configuration or characteristic of a screen, and is a technology that can dramatically improve a contrast ratio and reduce power consumption. As an example of local dimming, the brightness of a mini LED or micro LED corresponding to a dark screen is relatively dark to express a dark color, and the brightness of a mini LED or micro LED corresponding to a bright screen is relatively bright to produce a vivid color. I can express it.

The reflective sheet 12 reflects light. The reflective sheet 12 transmits light in the divergence direction of light emitted from the light source 11, and reflects the reflected light due to interfacial reflection or the like from the top in the divergence direction of the light. Through this, loss of light can be minimized. The reflective sheet 12 may perform light recycling.

The color conversion sheet 13 converts the color of light emitted from the light source 11. For example, the light of the mini LED or micro LED is blue light (450 nm). In this case, blue light needs to be converted to white light. The color conversion sheet 13 may transmit blue light and simultaneously convert blue light into white light.

The diffusion lens sheet 14 diffuses light. The diffusion lens sheet 14 includes a plurality of light diffusion lenses on one surface. As an example, the light diffusion lens may be formed in a pyramid shape to facilitate light diffusion.

The

diffusion sheets

15 and 18 may uniformly disperse incident light. The

diffusion sheets

15 and 18 are curable resins (for example, at least one of urethane acrylate, epoxy acrylate, ester acrylate, ester acrylate, and radical-generating monomers) to which light diffusing agent beads are added. It can be used alone or as a mixture) to cause light diffusion by the optical dispersion beads. Further, in the

diffusion sheets

15 and 18, a protrusion pattern (or protrusion) having a uniform or non-uniform size (for example, a sphere) may be disposed to facilitate light diffusion.

The

prism sheets

16 and 17 may condense incident light using an optical pattern formed on the surface and emit light to the liquid crystal panel 20. The

prism sheets

16 and 17 may be formed as an optical pattern layer in which an optical pattern in the form of a triangular array having a generally inclined surface of 45° is formed on the translucent base film to improve luminance in the front direction.

The reflective polarization sheet 19 is provided on the

prism sheets

16 and 17 and serves to recycle the light by transmitting one polarized light and reflecting the other polarized light downward to the light collected from the

prism sheets

16 and 17. .

The liquid crystal panel 20 modulates the light irradiated from the light source 11 in a predetermined pattern according to an electric signal. The modulated light passes through a color filter and a polarization filter disposed in front of the liquid crystal panel 20 to constitute a screen.

The configuration of the liquid crystal display device 1 according to an embodiment of the present invention has been described above. Hereinafter, various embodiments of the present application will assume a case of using a mini LED or micro LED as the light source 11 of the backlight unit, but including a light source 11 in which LEDs of uniform or various sizes are arranged directly. Various embodiments of the present disclosure may be applied to the backlight unit without limitation.

Hereinafter, an optical film according to various embodiments of the present disclosure will be described in detail.

Hereinafter, the optical film is defined as the diffusion lens sheet 14 of FIG. 1, or the diffusion lens sheet 14 and reflection sheet 12, color conversion sheet 13, diffusion lens sheet 14, and diffusion of FIG. It may be defined as a combination of at least one of the

sheets

15 and 18, the

prism sheets

16 and 17, and the reflective polarizing sheet 19.

Referring to FIG. 3, the optical film 30 may include a first base film 31 and a reflective pattern layer 32. The optical film 30 may transmit light emitted from a mini LED (light emitting diode) or a micro LED.

The first base film 31 may support the reflective pattern layer 32. For example, the first base film 31 may be made of a material such as PET, PC, or PP.

The reflective pattern layer 32 may transmit light in a divergence direction of light emitted from a light source, and reflect light reflected from an upper portion thereof due to interfacial reflection in the divergence direction of the light. Through this, loss of light can be minimized and reduction in luminance can be minimized. The reflective pattern layer 32 may perform light recycling.

The reflective pattern layer 32 may include a plurality of holes (holes or mini-holes) 32-1, 32-2, and 32-3. As an example, FIG. 4 shows a case where the reflective pattern layer 32 is viewed from the direction A. In the reflection pattern layer 32 of FIG. 4, a plurality of holes including a plurality of holes 32-1, 32-2 and 32-3 may be regularly arranged. Here, the plurality of holes may have various polygonal shapes such as a square as well as a circle.

Here, the plurality of holes 32-1, 32-2 and 32-3 may be arranged (or formed) to correspond to the position of the mini LED or the position of the micro LED. An embodiment of the location of the plurality of holes 32-1, 32-2, and 32-3, the location of the mini LED, and the arrangement between the locations of the micro LED will be described in detail below with reference to FIGS. 5 and 6.

5, a light source 53, an optical film 50, and an optical sheet 54 are disposed in parallel.

The light source 53 may include a plurality of mini LEDs or a plurality of micro LEDs 53-1.

The optical film 50 may include a first base film 51 and a reflective pattern layer 52.

For example, the first hole 52-1 and the mini LED or the micro LED 53-1 disposed in the first base film 51 may be arranged to be aligned with each other based on the axis B. Through this, at least a portion of the light emitted from the mini LED or micro LED 53-1 may pass through the optical film 50 through the first hole 52-1 disposed in the first base film 51. . In addition, at least some of the rest of the light passing through the optical film 50 may be reflected on the reflection pattern of the reflection pattern layer 52.

The optical sheet 54 may be at least one of various sheets included in FIG. 1. The optical sheet 54 may transmit or reflect the light transmitted from the optical film 50 again (55).

6, a light source 63, an optical film 60, and an optical sheet 64 are disposed in parallel.

The light source 63 may include a plurality of mini LEDs or a plurality of micro LEDs 63-1.

The optical film 60 may include a first base film 61 and a reflective pattern layer 62.

The plurality of holes formed in the reflective pattern layer 62 may be formed to insert a mini LED or a micro LED.

For example, the first hole 62-1 and the mini LED or micro LED 63-1 disposed in the first base film 61 may be arranged to be aligned with each other based on the axis C. In this case, the first hole 62-1 disposed in the first base film 61 may be formed so that the mini LED or the micro LED 63-1 is inserted along the axis C. For example, the diameter of the first hole 62-1 may be formed to be larger than the diameter of the mini LED or micro LED 53-1 by a predetermined length so that the mini LED or micro LED 63-1 is inserted. have.

According to the above-described example, at least a part of light emitted from the mini LED or micro LED 63-1 is transmitted through the optical film 60 through the first hole 62-1 disposed in the first base film 61. can do. In addition, at least some of the rest of the light transmitted through the optical film 60 may be reflected on the reflective pattern of the reflective pattern layer 62.

5 and 6, when the amount of light emitted from the mini LEDs or micro LEDs 53-1 and 63-1 is the same, the mini LED or micro LED 63-1 of the embodiment of FIG. 6 described above is a first hole Since it was inserted into (62-1), the light transmittance of the optical film 50 in the embodiment of FIG. 5 may be greater than the light transmittance of the optical film 60 in the embodiment of FIG. 6.

The optical sheet 64 may be at least one of various sheets included in FIG. 1. The optical sheet 64 may transmit or reflect the light transmitted through the optical film 50 (65).

Hereinafter, an optical film according to various embodiments of the present disclosure will be described in detail. Hereinafter, a configuration overlapping with the above-described optical film will be omitted for convenience of description.

Referring to FIG. 7, the optical film 70 may include a first base film 71, a first reflective pattern layer 72, and a second reflective pattern layer 73. Here, the first base film 71, the first reflective pattern layer 72, and the second reflective pattern layer 73 may be disposed parallel to each other.

For example, a plurality of holes included in the first reflective pattern layer 72 and a plurality of holes included in the second reflective pattern layer 73 may be disposed to correspond to each other. For example, the center of the first hole 72-1 of the first reflection pattern layer 72 and the center of the first hole 73-1 of the second reflection pattern layer 73 are aligned with respect to the axis D. Can be placed.

Referring to FIG. 8, the optical film 80 may include a first base film 81, a second base film 82, a reflective pattern layer 83, and a color conversion layer 84.

The first base film 81 and the second base film 82 may be disposed in parallel to protect the color conversion layer 84.

The color conversion layer 84 converts colors. The color conversion layer 84 may convert blue light emitted from the mini LED or micro LED into white light.

The color conversion layer 84 may be disposed between the first base film 81 and the second base film 82.

The color conversion layer 84 may include a red phosphor, a green phosphor, and inorganic particles. Here, the red phosphor or green phosphor is a material that forms red or green light by absorbing light emitted from a mini LED or micro LED. For example, a red phosphor is a KSF (K ₂ SiF ₆ :Mn4+) phosphor, and a green phosphor is a β-sialon phosphor. In addition, the inorganic particles are for inducing uniform scattering of light. Examples of inorganic particles include TiO2 and SiO2 having a diameter of several hundred nanometers.

For example, the color conversion layer 84 may be formed by stirring a red phosphor, a green phosphor, and an inorganic particle in a resin (silicone, acrylic, etc.). In this case, the color conversion layer 84 may be attached to the first base film 81 and the second base film 82.

For example, the color conversion layer 84 may include red phosphor, green phosphor, and inorganic particles according to a predefined weight ratio. Here, the predefined weight ratio is a weight ratio between the weight of the red phosphor, the weight of the green phosphor, and the inorganic particles determined based on the color coordinate values for white light.

Referring to FIG. 9, the color coordinate values for white light described above may be defined based on the Commission Internationale de l'Eclairage (CIE) color space 90. In this case, the color coordinate value for white light may be defined as an X coordinate value, a Y coordinate value, and a Z coordinate value defined in the color space 90.

For example, the X coordinate value and the Y coordinate value may be defined in 0.27 to 0.33, and the Z coordinate value may be defined as a dependent variable based on the defined X coordinate and Y coordinate.

For example, the weight ratio of the red phosphor is defined within 10% to 80%, the weight ratio of the green phosphor is defined within 10% to 80%, and the weight ratio of inorganic particles may be defined within 1% to 10%. have. In this case, it goes without saying that the total sum of the weight ratio of the red phosphor, the weight ratio of the green phosphor, and the weight ratio of the inorganic particles may be defined as 100% or less. In addition, when the weight ratio is not defined in %, the total sum of the weight ratio may be defined as 100 or less as well as more than 100.

Here, an example in which the weight ratio of the red phosphor is larger than the weight ratio of the green phosphor and the weight ratio of the green phosphor is set to be larger than the weight ratio of the inorganic particles will be described with reference to FIG. 10 below.

In the example of FIG. 10, the ratio of the weight of the red phosphor, the weight of the green phosphor, and the weight of the inorganic particles included in the color conversion layer is set to 66:44:5. Here, the blue light emitted from the mini LED or the micro LED is converted into white light while passing through the color conversion layer (or optical film). In addition, the light may be uniformly scattered to provide appearance characteristics without mura (101).

Referring to FIG. 11, the optical film 110 includes a first base film 111, a second base film 112, a color conversion layer 113, a reflection pattern layer 114, and a diffusion lens layer 115. can do.

The diffusion lens layer 115 may include a plurality of triangular pyramid-shaped lenses 115-1 to 115-5. Here, the plurality of lenses 115-1 to 115-5 may be referred to as a pyramid shape.

For example, the lenses 115-1 to 115-5 in the shape of a triangular pyramid may be regularly arranged (see FIG. 12). Here, the plurality of triangular pyramid-shaped lenses 115-1 to 115-5 may have the same size and the same shape, or different sizes but similar shapes. In addition, the diffusion lens layer 115 may be defined as including the first base film 111.

For example, the triangular pyramid shape may be defined based on the vertex angle θ (115-1-1). Here, the vertex angle θ (115-1-1) may be defined as an angle between two facing surfaces among four surfaces disposed on the triangular pyramid-shaped lens 115-1. For example, the apex angle can be defined within 40° to 150°.

For example, the height (115-1-3) of the bottom surface of the triangular pyramid-shaped lens 115-1 and the height (115-1-2) of the triangular pyramid-shaped lens 115-1 are based on the apex angle θ. Can be defined according to For example, when the vertex angle θ is 90°, the height of the bottom surface of the triangular pyramid-shaped lens 115-1 (115-1-3) and the height of the triangular pyramid-shaped lens 115-1 (115-1- The ratio of 2) can be defined as 2:1. In this case, the height (115-1-3) of the bottom surface of the triangular pyramid-shaped lens 115-1 may be defined as 20 μm, and the height (115-1-2) of the triangular pyramid-shaped lens 115-1 may be defined as 10 μm. have.

In various embodiments of the present disclosure described above, four surfaces (or lenses) disposed on a triangular pyramid-shaped lens of the optical film 110 may be formed identically (jointly). However, it is not limited thereto. For example, of the four faces arranged on the triangular pyramid-shaped lens of the optical film, facing faces may be congruent with each other, and the adjacent faces may be formed in different shapes.

In the above-described example, since the light of the mini LED or the micro LED is lightly separated (or light diffused) by the action of the diffusion lens layer 115, a hot spot due to the concentration of light may be reduced.

13, the optical film 130 includes a first base film 131, a second base film 132, a color conversion layer 133, a reflective pattern layer 134, a diffusion lens layer 135, and an inorganic film. It may include a particle layer 136.

Here, the inorganic particle layer 136 may include inorganic particles. For example, the inorganic particle layer 136 may be formed by stirring an inorganic particle and a resin. In this case, the inorganic particle layer 136 may be attached to one surface of the first base film 131.

In the above example, the inorganic particle layer 136 may further include the above-described red phosphor and green phosphor. In addition, the position of the inorganic particle layer 136 may be disposed in exchange with the position of the color conversion layer 133. In addition, the inorganic particle layer 136 may be attached to one surface of the second base film 132.

Referring to FIG. 14, the optical film 140 may include a first base film 141, a reflective pattern layer 142, and a filling member 143.

Hereinafter, the contents of the color conversion layer described above will be equally applicable to the filling member 143. Accordingly, the contents of the above-described color conversion layer that are equally applicable to the filling member 143 will be omitted for convenience of description.

The filling member 143 may perform color conversion. Specifically, the charging member 143 may perform color conversion of light emitted from the mini LED or the micro LED. For example, blue light emitted from the mini LED or the micro LED may be converted into white light by passing through the charging member 143.

The filling member 143 may be accommodated in a plurality of holes according to various embodiments of the present disclosure described above. For example, the filling member 143 may be filled through an ink jet. In this case, the first base film 141 may be an inkjet sheet. As an example, the filling member may have the same properties as the color conversion layer described above, or may be patterned with at least one phosphor or quantum dot (QD).

Referring to Figure 15, in the case of a typical mobile phone (MP, mobile phone) is implemented in a pixel size of 40 μm to 80 μm to exhibit 300 PPI/DPI (pixel/dot per inch) to 600 PPI/DPI, whereas the above-described In the case of the optical film 140 of FIG. 14, a 20 μm pixel size can be implemented, and thus 1200 PPI/DPI to 1300 PPI/DPI can be exhibited, so that a higher resolution can be implemented.

In addition, in the case of the optical film 140 of FIG. 14, since a reflective pattern having a light reflecting function and a filling member having a color conversion function are patterned into one layer, a thinner and lighter optical film 140 is implemented. Can be.

Hereinafter, an arrangement of an optical film and a mini LED or micro LED according to various embodiments of the present disclosure described above will be described in detail with reference to FIGS. 16 to 19.

Referring to FIG. 16, a light source 163,

optical films

161 and 162, and optical sheets 164 may be disposed in parallel.

For example, a part of blue light emitted from the first LED 163-1 of the light source 163 may pass through the charging member 162-1 and the rest may be reflected to the reflective pattern layer 162. Here, some of the blue light emitted from the first LED 163-1 may be color converted into white light by passing through the charging member 162-1. The color-converted light may pass through the first base film 161 and the optical sheet 164 to implement a predetermined light distribution 165.

Referring to FIG. 17, a light source 174,

optical films

171, 172, 173, and optical sheets 175 may be disposed in parallel.

For example, some of the blue light emitted from the first LED 174-1 of the light source 174 may pass through the charging member 172-1 and the rest may be reflected to the reflective pattern layer 172. Here, some of the blue light emitted from the first LED 174-1 may be color-converted to white light by passing through the charging member 172-1. The color-converted light may pass through the first base film 171, the first diffusion lens layer 173, and the optical sheet 175 to achieve a predetermined brightness 176. Here, the color-converted light may be divided by the first diffusion lens layer 173 to be relatively more diffused than the predetermined light distribution 163 of FIG. 16.

Referring to FIG. 18, a light source 183,

optical films

181 and 182,

color conversion sheets

184, 185 and 186, and optical sheets 187 may be disposed in parallel.

For example, a part of blue light emitted from the first LED 183-1 of the light source 183 may pass through the first hole 182-1 and the rest may be reflected to the reflective pattern layer 182. Here, some of the blue light emitted from the first LED 183-1 may be color converted into white light by passing through the color conversion layer 185 of the

color conversion sheets

184, 185, 186. The color-converted light may pass through the optical sheet 187 to implement a predetermined light distribution 188.

Referring to FIG. 19, a light source 196,

color conversion sheets

193, 194, 195,

optical films

191, 192, and optical sheets 197 may be disposed in parallel.

Here, the plurality of LEDs 196-1, 196-2, and 196-3 of the light source 196 may perform local dimming.

For example, blue light emitted from the plurality of LEDs 196-1, 196-2, and 196-3 of the light source 196 is converted into white light while passing through the

color conversion sheets

193, 194, and 195. Some of the converted white light may pass through the plurality of holes 192-1, 192-2 and 192-3, and the rest may be reflected to the reflective pattern layer 192. In this case, the light converted to white light may pass through the optical sheet 197 to implement predetermined light distributions 198-1, 198-2, and 198-3. Here, as the local dimming of the plurality of LEDs (196-1, 196-2, 196-3) is performed, the intensity of blue light emitted from the plurality of LEDs (196-1, 196-2, 196-3) is different. It is controlled so that the sizes of the predetermined light distributions 198-1, 198-2, and 198-3 may be different.

In addition, according to various embodiments of the present disclosure, when performing local dimming, a specific mini LED or micro LED may be controlled to be turned off in order to implement a complete black color. In this case, interference of light may occur in a region implementing a black color by at least one of the turned off mini LEDs or mini LEDs or micro LEDs arranged adjacent to the micro LEDs. However, the above-described reflective pattern layer 192 can block such interference.

According to various embodiments of the present invention described above, the optical film can minimize luminance loss by reflecting light emitted from a mini LED or micro LED, and adjust the light distribution through local dimming of the mini LED or micro LED. have.

As described above, embodiments of the present invention have been shown and described, but those skilled in the art will make various changes in form and details without departing from the spirit and scope of the present embodiment as defined by the appended claims and equivalents thereto. You will understand that you can.

Claims

In the optical film that transmits light emitted from a mini LED (light emitting diode) or micro LED,

A first base film; And

Including; a reflective pattern layer disposed on one side of the first base film,

The reflective pattern layer,

Containing, an optical film comprising; a plurality of holes disposed to correspond to the location of the mini LED or the location of the micro LED so as to transmit the light emitted from the mini LED or the micro LED.
According to claim 1,

The plurality of holes,

Formed so that the mini LED or the micro LED is inserted, the optical film.
According to claim 1,

The centers of the plurality of holes and the centers of the mini LED or the micro LED are arranged to be aligned by one axis, the optical film.
According to claim 1,

The plurality of holes,

An optical film in which a filling member for color conversion of the light emitted from the mini LED or the micro LED is accommodated.
According to claim 4,

The first base film is a sheet for an ink jet,

The filling member is an optical film that is filled through the ink jet.
According to claim 4,

The filling member,

An optical film comprising a red phosphor, a green phosphor, and inorganic particles that induce uniform scattering of the light according to a predefined weight ratio.
The method of claim 6,

The predefined weight ratio is,

The optical film, which is a ratio between the weight of the red phosphor, the weight of the green phosphor, and the weight of the inorganic particles determined based on a color coordinate value for white light.
The method of claim 7,

The color coordinate value for the white light,

Optical film, which is an X coordinate value, a Y coordinate value and a Z coordinate value defined in the Commission internationale de l'Eclairage (CIE) color space.
The method of claim 7,

The weight ratio of the red phosphor is greater than the weight ratio of the green phosphor, and the weight ratio of the green phosphor is greater than the weight ratio of the inorganic particles.
The method of claim 7,

The weight ratio of the red phosphor is defined within 10% to 80%, the weight ratio of the green phosphor is defined within 10% to 80%, and the weight ratio of the inorganic particles is defined from 1% to 10%, Optical film.
According to claim 1,

A second base film disposed parallel to the first base film; And

A color conversion layer disposed between the other side of the first base film and one side of the second base film; further comprising,

Here, the color conversion layer,

An optical film comprising a red phosphor, a green phosphor, and inorganic particles that induce uniform scattering of the light according to a predefined weight ratio,
The method of claim 11,

The optical film further comprising; a diffusion lens layer disposed on the other side of the second base film and including a plurality of triangular pyramid-shaped lenses.
The method of claim 11,

Inorganic particle layer comprising the inorganic particles; further comprising, an optical film.
The method of claim 11,

The optical film further comprising a; reflective pattern layer disposed on the other side of the first base film.
According to claim 1,

The mini LED or the micro LED,

Optical film, individually controlled light intensity and on-off.