KR20130009026A - Optical member and display device having the same - Google Patents

Abstract

PURPOSE: An optical member and a display device including the same are provided to protect wavelength conversion particles by a first and a second guide member. CONSTITUTION: A display device includes a light guide member(200), a light source(400) and a display panel. The light guide member includes a first guide portion(210), a second guide portion(220) and multiple wavelength conversion portions(250). The first guide portion is arranged beneath a display panel. The second guide portion is arranged on the first guide portion. Multiple wavelength conversion portions are interposed between the first and the second guide portion.

Description

Optical member and display including the same {OPTICAL MEMBER AND DISPLAY DEVICE HAVING THE SAME}

Embodiments relate to an optical member and a display device including the same.

Recently, a flat panel display such as a liquid crystal display (LCD), a plasma display panel (PDP), or an organic light emitting diode (OLED) has been developed in place of the conventional CRT.

The liquid crystal display device includes a thin film transistor substrate, a color filter substrate, and a liquid crystal display panel in which liquid crystal is injected between both substrates. Since the liquid crystal display panel is a non-light emitting device, a backlight unit for supplying light to the bottom surface of the thin film transistor substrate is positioned. Light transmitted from the backlight unit is adjusted according to the arrangement of liquid crystals.

The backlight unit is divided into edge type and direct type according to the position of the light source. The edge type is a structure in which a light source is provided on a side surface of the light guide plate.

The direct type is a structure that is mainly developed with the size of a liquid crystal display device being enlarged. One or more light sources are arranged on the lower surface of the liquid crystal display panel to supply light to the liquid crystal display panel.

The direct-type backlight unit has advantages in that it can utilize a larger number of light sources than the edge-type backlight unit and can secure a high luminance, but has a disadvantage that the thickness becomes thicker than the edge type in order to ensure uniformity of brightness have.

In order to overcome this problem, a quantum dot bar in which a plurality of quantum dots dispersed in a red wavelength or a green wavelength is dispersed is provided in front of a blue LED emitting blue light constituting a backlight unit, Thus, light mixed with blue light, red light and green light by a plurality of quantum dots dispersed in the quantum dot bar is incident on the light guide plate to provide white light.

At this time, when white light is provided to the light guide plate using the quantum dot bar, high color reproduction can be realized.

The backlight unit may include an FPCB (Flexible Printed Circuits Board) for transmitting and supplying LEDs and signals to one side of a blue LED emitting blue light, and an adhesive member may be further provided on the lower surface of the FPCB.

As such, when a light emitted from a blue LED is leaked, a display device for displaying an image in various forms using white light provided to the light guide plate through the quantum dot bar is widely used.

A display device to which such a quantum dot is applied is disclosed in Korean Patent Laid-Open Publication No. 10-2011-0068110.

Embodiments provide an optical member and a display device that can be easily manufactured with improved color reproducibility and reliability.

In one embodiment, a display device includes a light guide member; A light source disposed on a side of the light guide member; And a display panel disposed on the light guide member, wherein the light guide member comprises: a first guide part disposed below the display panel; A second guide part disposed on the first guide part; And the first guide part; And a plurality of wavelength converters interposed between the second guide parts.

In one embodiment, a display device includes: a display panel; A wavelength conversion guide member disposed under the display panel; And a light source for injecting light into the side surface of the wavelength conversion guide member, wherein the wavelength conversion guide member includes a plurality of wavelength conversion units for converting wavelengths of light incident through the side surface; A first guide part disposed under the wavelength conversion parts and configured to guide light incident through the side surface to the wavelength conversion parts; And a second guide part disposed on the wavelength converters and configured to guide light incident through the side surface to the wavelength converters.

In one embodiment, an optical member includes: a first guide part; A second guide part disposed on the first guide part; A plurality of wavelength converters interposed between the first guide part and the second guide part; And a plurality of optical path changing units disposed adjacent to the wavelength converters, respectively.

The optical member and the display device according to the exemplary embodiment sandwich the wavelength conversion parts by using the first guide part and the second guide part. Accordingly, the wavelength converting particles included in the wavelength converting parts may be effectively protected from chemical shock such as external moisture and / or oxygen by the first guide part and the second guide part.

Accordingly, the optical member and the display device according to the embodiment can have improved reliability and durability.

In addition, the wavelength conversion parts may be disposed corresponding to the optical path changing parts formed on the first guide part and / or the second guide part. Accordingly, the light incident on the first guide portion and the second guide portion is guided by total reflection. When the guided light is incident on the light path changing parts, the light path may be changed to an angle larger than the total reflection critical angle.

In this case, since the wavelength converters are disposed adjacent to the optical path changing parts, the light whose path is changed may be incident on the wavelength converting parts. Accordingly, the light whose wavelength is converted by the wavelength converters may be emitted upward.

Since the wavelength converters are disposed adjacent to the optical path changing parts, the wavelength of the light emitted from the upper surface of the light guide member may be effectively converted. Accordingly, the display device according to the embodiment may have an improved color reproduction rate.

In addition, most of the light emitted from the upper surface of the light guide member is light incident on the light path changing units and whose path is changed. Accordingly, even if the wavelength converters are disposed only at positions adjacent to the optical path changing units, the display device according to the exemplary embodiment may have a high color reproduction rate. Accordingly, the amount of wavelength converting particles used to manufacture the display device according to the embodiment can be reduced.

1 is an exploded perspective view showing a liquid crystal display device according to a first embodiment.
2 is an exploded perspective view showing the light guide member.
3 is a cross-sectional view illustrating a light emitting diode, a light guide member, and a reflective sheet.
4 is a view illustrating a process in which light is guided by the light guide member.
5 is a sectional view showing the light guide member according to the second embodiment.
6 is a cross-sectional view showing a cross section of the light guide member according to the third embodiment.
7 is a cross-sectional view showing a cross section of the light guide member according to the fourth embodiment.
8 is a cross-sectional view showing a cross section of the light guide member according to the fifth embodiment.

In the description of the embodiments, it is described that each substrate, frame, sheet, layer or pattern is formed "on" or "under" each substrate, frame, sheet, In this case, "on" and "under " all include being formed either directly or indirectly through another element. In addition, the upper or lower reference of each component is described with reference to the drawings. The size of each component in the drawings may be exaggerated for the sake of explanation and does not mean the size actually applied.

1 is an exploded perspective view showing a liquid crystal display device according to a first embodiment. 2 is an exploded perspective view showing the light guide member. 3 is a cross-sectional view illustrating a light emitting diode, a light guide member, and a reflective sheet. 4 is a view illustrating a process in which light is guided by the light guide member.

1 to 4, the liquid crystal display according to the embodiment includes a backlight unit 10 and a liquid crystal panel 20.

The backlight unit 10 emits light to the liquid crystal panel 20. The backlight unit 10 may irradiate uniform light onto the bottom surface of the liquid crystal panel 20 using a surface light source.

The backlight unit 10 is disposed under the liquid crystal panel 20. The backlight unit 10 includes a bottom cover 100, a reflective sheet 300, a light source, for example, a plurality of light emitting diodes 400, a printed circuit board 401, a light guide member 200, and a plurality of light emitting diodes. Optical sheets 500.

The bottom cover 100 has a shape in which an upper portion thereof is opened. The bottom cover 100 accommodates the light guide member 200, the light emitting diodes 400, the printed circuit board 401, the reflective sheet 300, and the optical sheets 500.

The reflective sheet 300 is disposed below the light guide member 200. In more detail, the reflective sheet 300 is disposed between the light guide member 200 and the bottom surface of the bottom cover 100. The reflective sheet 300 reflects the light emitted from the lower surface of the light guide member 200 upward.

The light emitting diodes 400 are light sources for generating light. The light emitting diodes 400 are disposed on one side of the light guide member 200. The light emitting diodes 400 generate light and enter the light guide member 200 through a side surface of the light guide member 200.

The light emitting diodes 400 may be blue light emitting diodes generating blue light or UV light emitting diodes generating ultraviolet light. That is, the light emitting diodes 400 may generate blue light having a wavelength band between about 430 nm and about 470 nm or ultraviolet rays having a wavelength band between about 300 nm and about 400 nm.

The light emitting diodes 400 are mounted on the printed circuit board 401. The light emitting diodes 400 are disposed under the printed circuit board 401. The light emitting diodes 400 are driven by receiving a driving signal through the printed circuit board 401.

The printed circuit board 401 is electrically connected to the light emitting diodes 400. The printed circuit board 401 may mount the light emitting diodes 400. The printed circuit board 401 is disposed inside the bottom cover 100.

The light guide member 200 is disposed in the bottom cover 100. The light guide member 200 is disposed on the reflective sheet 300. The light guide member 200 emits light incident from the light emitting diodes 400 upward through total reflection, refraction, and scattering.

In addition, the light guide member 200 converts the wavelength of the light emitted from the light emitting diodes 400. The wavelength-converted light and the unconverted light are emitted upward through the upper surface of the light guide member 200. That is, the light guide member 200 is a wavelength conversion guide member for guiding light emitted to the light emitting diodes and simultaneously converting wavelengths.

For example, when the light emitting diodes 400 are blue light emitting diodes, the light guide member 200 may convert blue light emitted upward from the light guide member 200 into green light and red light. have. That is, the light guide member 200 converts a part of the blue light into green light having a wavelength band between about 520 nm and about 560 nm, and converts another part of the blue light into a wavelength band between about 630 nm and about 660 nm. Branches can be converted to red light.

In addition, when the light emitting diodes 400 are UV light emitting diodes, the light guide member 200 may convert ultraviolet light emitted from the upper surface of the light guide member 200 into blue light, green light, and red light. have. That is, the light guide member 200 converts a part of the ultraviolet light into blue light having a wavelength band between about 430 nm and about 470 nm, and converts another part of the ultraviolet light into a wavelength band between about 520 nm and about 560 nm. The branches can be converted to green light and another portion of the ultraviolet light can be converted to red light having a wavelength band between about 630 nm and about 660 nm.

Accordingly, the light that is not converted and is emitted to the upper surface of the light guide member 200 and the light converted by the light guide member 200 may form white light. That is, blue light, green light, and red light may be combined to allow white light to enter the liquid crystal panel 20.

2 to 4, the light guide member 200 includes a first guide part 210, a second guide part 220, a plurality of first optical path changing parts 230, and a plurality of agents. It includes two optical path changers 240 and a plurality of wavelength converters 250.

The first guide part 210 is disposed under the liquid crystal panel 20. In addition, the first guide part 210 is disposed on the reflective sheet 300. The first guide portion 210 has a plate shape. The first guide part 210 is transparent. Examples of the material used as the first guide part 210 include acrylic resins formed by methyl acrylate, ethyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, and the like. For example, a polymer such as polymethylmethaacrylate (PMMA) or polycarbonate (PC) may be used as the first guide part 210. In addition, glass may be used as the first guide part 210. More specifically, the glass used as the first guide portion 210 may include silicon oxide, titanium oxide, aluminum hydroxide, magnesium oxide or zinc oxide. The first guide portion 210 may have a thickness of about 0.25 mm to about 0.75 mm.

The second guide part 220 is disposed on the first guide part 210. The second guide part 220 faces the first guide part 210. The second guide part 220 may be spaced apart from the first guide part 210 at a predetermined interval. The second guide part 220 may sandwich the wavelength converters 250 together with the first guide part 210. In addition, the second guide part 220 is disposed under the liquid crystal panel. The second guide part 220 is disposed under the optical sheets.

The second guide part 220 has a plate shape. The second guide part 220 is transparent. Examples of the material used as the second guide part 220 may be the same as the material used as the first guide part 210. The second guide part 220 may have a thickness of about 0.25 mm to about 0.75 mm. The first guide part 210 and the second guide part 220 may have thicknesses corresponding to each other. That is, the thickness of the first guide portion 210 and the thickness of the second guide portion 220 may be substantially the same.

The first optical path changing units 230 correspond to the wavelength converters 250, respectively. In more detail, the first optical path changing units 230 are adjacent to the wavelength converters 250, respectively. The first optical path changing units 230 may be in direct contact with the wavelength converters 250, respectively. The first optical path changing units 230 may be disposed directly below the wavelength converters 250.

In addition, the first optical path changing parts 230 may be formed on an upper surface of the first guide part 210. The first optical path changing parts 230 may be formed at a portion of the upper surface of the first guide part 210 to which the wavelength converters 250 contact.

The first optical path changing parts 230 may include an uneven pattern. In more detail, the first optical path changing units 230 may include a scattering pattern.

The first optical path changing units 230 may be spaced apart from each other. In this case, the distance D between the first optical path changing parts 230 may become smaller as the distance from the light emitting diode 400 increases.

The second optical path changing units 240 correspond to the wavelength converters 250, respectively. In more detail, the second optical path changing units 240 are adjacent to the wavelength converters 250, respectively. The second optical path changing units 240 may be in direct contact with the wavelength converters 250, respectively. The second optical path changing units 240 may be disposed directly on the wavelength converters 250.

In addition, the second optical path changing parts 240 may be formed on the bottom surface of the second guide part 220. The second optical path changing parts 240 may be formed at a portion of the bottom surface of the second guide part 220 to which the wavelength converters 250 contact.

The second optical path changing parts 240 may include an uneven pattern. In more detail, the second optical path changing units 240 may include a scattering pattern.

The second optical path changing units 240 may be spaced apart from each other. In this case, the distance between the second optical path changing units 240 may become smaller as the distance from the light emitting diode 400 increases.

The wavelength converters 250 are interposed between the first guide part 210 and the second guide part 220. That is, the wavelength conversion parts 250 are sandwiched by the first guide part 210 and the second guide part 220. The wavelength converters 250 are disposed corresponding to the first optical path changing units 230, respectively. In more detail, the wavelength converters 250 are disposed adjacent to the first optical path changing units 230, respectively. The wavelength converters 250 may be in direct contact with the first optical path changing units 230, respectively. In addition, the wavelength converters 250 are disposed corresponding to the second optical path changing units 240, respectively. In more detail, the wavelength converters 250 are disposed adjacent to the second optical path changing units 240, respectively. The wavelength converters 250 may be in direct contact with the second optical path changers 240, respectively.

The distance D between the wavelength converters 250 may become smaller as the distance D is farther from the light emitting diode 400. The wavelength converters 250 form a wavelength conversion pattern 203 between the first guide part 210 and the second guide part 220.

The wavelength converters 250 may have a dot shape when viewed from the top side. Unlike this, the wavelength converters 250 may have a line shape when viewed from the top side.

The wavelength converters 250 may convert the wavelength of incident light. The wavelength converters 250 may convert the wavelength of the incident light into a longer wavelength. As shown in FIGS. 3 and 4, the wavelength converter 220 includes a host 251 and a plurality of wavelength converting particles 252.

The host 251 is disposed between the first guide part 210 and the second guide part 220. The host 251 may be in close contact with the first guide part 210 and the second guide part 220. In more detail, the host 251 may be in close contact with the first optical path changing unit 230 and the second optical path changing unit 240. That is, the host 251 may correspond to the first optical path changing unit 230 and the second optical path changing unit 240, respectively.

The host 251 surrounds the wavelength conversion particles 252. That is, the host 251 uniformly distributes the wavelength conversion particles 252 therein. The host 251 may be made of a polymer. The host 251 is transparent. That is, the host 251 may be formed of a transparent polymer.

Examples of the material used as the host 251 may be a silicone resin or an epoxy resin.

The refractive index of the host 251 may be different from the refractive index of the first guide portion 210 and the refractive index of the second guide portion 220. In more detail, the refractive index of the host 251 may be greater than that of the first guide portion 210 and the second guide portion 220. For example, the refractive index of the first guide portion 210 and the second guide portion 220 may be about 1.45 to about 1.54, and the refractive index of the host 251 may be about 1.55 to about 1.64.

The wavelength converting particles 252 are disposed in the host 251. In more detail, the wavelength conversion particles 252 may be uniformly dispersed in the host 251.

The wavelength conversion particles 252 convert the wavelength of light emitted from the light emitting diodes 400. The wavelength converting particles 252 receive light emitted from the light emitting diodes 400 to convert wavelengths. For example, the wavelength conversion particles 252 may convert blue light emitted from the light emitting diodes 400 into green light and red light. That is, some of the wavelength converting particles 252 convert the blue light into green light having a wavelength band between about 520 nm and about 560 nm, and another part of the wavelength converting particles 252 converts the blue light. May be converted into red light having a wavelength band between about 630 nm and about 660 nm.

Alternatively, the wavelength conversion particles 252 may convert ultraviolet light emitted from the light emitting diodes 400 into blue light, green light, and red light. That is, some of the wavelength converting particles 252 convert the ultraviolet light into blue light having a wavelength band of about 430 nm to about 470 nm, and another of the wavelength converting particles 252 converts the ultraviolet light to about Green light having a wavelength band between 520 nm and about 560 nm. In addition, another portion of the wavelength conversion particles 252 may convert the ultraviolet light into red light having a wavelength band between about 630 nm and about 660 nm.

That is, when the light emitting diodes 400 are blue light emitting diodes generating blue light, wavelength converting particles 252 for converting blue light into green light and red light may be used. Alternatively, when the light emitting diodes 400 are UV light emitting diodes that generate ultraviolet rays, wavelength converting particles 252 for converting ultraviolet rays into blue light, green light, and red light may be used.

The wavelength conversion particles 252 may be a quantum dot (QD). The quantum dot may include a core nanocrystal and a shell nanocrystal surrounding the core nanocrystal. In addition, the quantum dot may include an organic ligand bound to the shell nanocrystal. In addition, the quantum dot may include an organic coating layer surrounding the shell nanocrystals.

The shell nanocrystals may be formed of two or more layers. The shell nanocrystals are formed on the surface of the core nanocrystals. The quantum dot may convert the wavelength of the light incident on the core core crystal into a long wavelength through the shell nanocrystals forming the shell layer and increase the light efficiency.

The quantum dot may include at least one of a group II compound semiconductor, a group III compound semiconductor, a group V compound semiconductor, and a group VI compound semiconductor. More specifically, the core nanocrystals may include Cdse, InGaP, CdTe, CdS, ZnSe, ZnTe, ZnS, HgTe or HgS. The shell nanocrystals may include CuZnS, CdSe, CdTe, CdS, ZnSe, ZnTe, ZnS, HgTe or HgS. The diameter of the quantum dot may be 1 nm to 10 nm.

The wavelength of light emitted from the quantum dots can be controlled by the size of the quantum dots or the molar ratio of the molecular cluster compound and the nanoparticle precursor in the synthesis process. The organic ligand may include pyridine, mercapto alcohol, thiol, phosphine, phosphine oxide, and the like. The organic ligands serve to stabilize unstable quantum dots after synthesis. After synthesis, a dangling bond is formed on the outer periphery, and the quantum dots may become unstable due to the dangling bonds. However, one end of the organic ligand is in an unbonded state, and one end of the unbound organic ligand bonds with the dangling bond, thereby stabilizing the quantum dot.

Particularly, when the quantum dot has a size smaller than the Bohr radius of an exciton formed by electrons and holes excited by light, electricity or the like, a quantum confinement effect is generated to have a staggering energy level and an energy gap The size of the image is changed. Further, the charge is confined within the quantum dots, so that it has a high luminous efficiency.

Unlike general fluorescent dyes, the quantum dots vary in fluorescence wavelength depending on the particle size. That is, as the size of the particle becomes smaller, it emits light having a shorter wavelength, and the particle size can be adjusted to produce fluorescence in a visible light region of a desired wavelength. In addition, since the extinction coefficient is 100 to 1000 times higher than that of a general dye, and the quantum yield is also high, it produces very high fluorescence.

The quantum dot can be synthesized by a chemical wet process. Here, the chemical wet method is a method of growing particles by adding a precursor material to an organic solvent, and the quantum dots can be synthesized by a chemical wet method.

In addition, a sealing part 260 may be interposed between the first guide part 210 and the second guide part 220. The sealing part 260 may be disposed outside the first guide part 210 and the second guide part 220. The sealing unit 260 may surround the wavelength converters 250. The sealing part 260 may have a closed loop shape. The sealing part 260 may be attached to an upper surface of the first guide part 210 and a lower surface of the second guide part 220. The sealing part 260 may seal a space between the first guide part 210 and the second guide part 220.

In addition, the reflector 270 may be disposed on the side of the first guide part 210 and the side of the second guide part 220. The reflector 270 may be disposed on the remaining sides except for the side where the light emitting diode 400 is disposed.

The reflector 270 leaks light that leaks to the side of the first guide part 210 and the side of the second guide part 220 into the first guide part 210 and the second guide part 220. Can be reflected again.

The optical sheets 500 are disposed on the light guide member 200. The optical sheets 500 change or improve characteristics of light emitted from the upper surface 202 of the light guide member 200 to supply the light to the liquid crystal panel 20.

The optical sheets 500 may be a diffusion sheet 501, a first prism sheet 502, and a second prism sheet 503.

The diffusion sheet 502 is disposed on the light guide member 200. The diffusion sheet 502 improves the uniformity of light passing therethrough. The diffusion sheet 501 may include a plurality of beads.

The first prism sheet 502 is disposed on the diffusion sheet 501. The second prism sheet 503 is disposed on the first prism sheet 502. The first prism sheet 502 and the second prism sheet 503 increase the straightness of the light passing through.

The liquid crystal panel 20 is disposed on the optical sheets 500. In addition, the liquid crystal panel 20 is disposed on the panel guide 23. The liquid crystal panel 20 may be guided by the panel guide 23.

The liquid crystal panel 20 displays an image by adjusting the intensity of light passing through the liquid crystal panel 20. That is, the liquid crystal panel 20 is a display panel that displays an image by using light emitted from the backlight unit 10. The liquid crystal panel 20 includes a TFT substrate 21, a color filter substrate 22, and a liquid crystal layer interposed between the two substrates. In addition, the liquid crystal panel 20 includes polarization filters.

Although not shown in detail in the drawings, the TFT substrate 21 and the color filter substrate 22 will be described in detail. In the TFT substrate 21, a plurality of gate lines and data lines cross each other to define pixels, and respective intersections are performed. A thin flim transistor (TFT) is provided in each region and is connected in one-to-one correspondence with the pixel electrode mounted in each pixel. The color filter substrate 22 includes a color filter of R, G, and B colors corresponding to each pixel, a black matrix bordering each of them, covering a gate line, a data line, a thin film transistor, and the like, and a common electrode covering all of them. Include.

At the edge of the liquid crystal panel 20, a driving PCB 25 is provided to supply driving signals to the gate line and the data line.

The driving PCB 25 is electrically connected to the liquid crystal panel 20 by a chip on film (COF) 24. Here, the COF 24 may be changed to a tape carrier package (TCP).

As shown in FIG. 4, the light emitted from the light emitting diode 400 is incident on the side surface of the light guide member 200. In more detail, the light (L1, L2) emitted from the light emitting diode 400 may be incident through the side of the first guide portion 210 and the side of the second second guide portion 220.

Thereafter, the light path incident to the light L1 incident through the side surface of the first guide part 210 may be changed by the first light path changing part 230. The light whose light path is changed as described above may be converted by the wavelength conversion particles 252 and emitted upward.

In addition, an optical path of the light L2 incident through the side surface of the second guide part 220 may be changed by the second optical path changing part. As such, the light whose light path is changed may be wavelength-converted by the wavelength conversion particles 252, reflected by the reflective sheet 300, and emitted upward.

That is, the light incident on the first guide part 210 and the second guide part 220 is guided by total reflection. When the guided light is incident on the first optical path changing parts 230 and the second optical path changing parts 240, the optical path may be changed to an angle larger than the total reflection critical angle.

In this case, since the wavelength converters 250 are disposed adjacent to the first optical path changing parts 230 and the second optical path changing parts 240, the light whose path is changed is converted into the wavelength converting parts 250. May be incident on. Accordingly, the light whose wavelength is converted by the wavelength converters 250 may be emitted upward.

Since the wavelength converters 250 are disposed adjacent to the first optical path changing parts 230 and the second optical path changing parts 240, the first optical path changing parts 230 and the second optical paths are arranged. Light whose path is changed by the path changing units 240 may be easily incident on the wavelength converters 250. Accordingly, the wavelength of the light emitted from the upper surface of the light guide member 200 can be effectively converted. Accordingly, the liquid crystal display according to the embodiment may have an improved color reproduction rate.

Accordingly, most of the light emitted from the upper surface of the light guide member 200 is incident on the first light path changing parts 230 and the second light path changing parts 240 to change the path. Although the wavelength converters 250 are disposed only at positions adjacent to the first optical path changing units 230 and the second optical path changing units 240, the liquid crystal display according to the exemplary embodiment may have a high color reproduction rate. Can be. Accordingly, the amount of wavelength converting particles 252 used to manufacture the liquid crystal display according to the embodiment can be reduced.

Therefore, the liquid crystal display device according to the embodiment can be easily manufactured. That is, the liquid crystal display according to the embodiment may have an improved color reproducibility even when a small amount of wavelength conversion particles 252 are used. Therefore, the liquid crystal display according to the embodiment can be manufactured at low cost.

In addition, the distance D between the wavelength converters 250 may become smaller as the distance from the light emitting diodes 400 increases. Accordingly, a phenomenon in which the luminance of the portion close to the light emitting diode 400 is relatively high is prevented, and the LCD according to the embodiment may have improved luminance uniformity.

In addition, the wavelength conversion particles 252 are disposed in the light guide member 200. Accordingly, the light guide member 200 has not only a light guide function but also a wavelength conversion function of light.

Therefore, the liquid crystal display according to the embodiment may have a simple and slim structure. That is, the liquid crystal display according to the embodiment can effectively convert the wavelength of the light emitted from the light emitting diodes 400 without using an additional member such as a light conversion sheet.

In addition, the wavelength conversion particles 252 may directly convert the wavelength of light incident on the light guide member 200 from the light emitting diodes 400.

Thus, the liquid crystal display according to the embodiment may have an improved color reproducibility and luminance.

In addition, the liquid crystal display according to the exemplary embodiment sandwiches the wavelength converters 250 using the first guide portion 210 and the second guide portion 220. Accordingly, the wavelength conversion particles 252 may be effectively protected from chemical shock such as external moisture and / or oxygen by the first guide portion 210 and the second guide portion 220. .

Therefore, the liquid crystal display according to the embodiment may have improved reliability and durability.

5 is a sectional view showing the light guide member according to the second embodiment. In the description of the present embodiment, reference is made to the description of the foregoing embodiment. That is, the foregoing description of the liquid crystal display device may be essentially combined with the description of the present liquid crystal display device, except for the changed part.

Referring to FIG. 5, the wavelength converters 250 may directly contact the top surface of the first guide part 210 and may directly contact the bottom surface of the second guide part 220. In this case, an uneven pattern or scattering pattern may not be formed on the upper surface of the first guide part 210 and the lower surface of the second guide part 220.

In this case, the host 251 of the wavelength converters 250 may have a refractive index similar to that of the first guide part 210 and the second guide part 220. That is, the refractive index of the host 251 may correspond to the refractive index of the first guide portion 210 and the refractive index of the second guide portion 220.

Accordingly, the light incident on the first guide part 210 is totally reflected at the portion where the wavelength converters 250 are not disposed, and the part where the host 251 and the first guide portion 210 are in contact with each other. Incident to the wavelength converters 250. Accordingly, the path of the light incident on the first guide part 210 may be changed, and at the same time, the wavelength may be converted and emitted upward.

Similarly, the light incident on the second guide portion 220 is totally reflected at the portion where the wavelength converters 250 are not disposed, and at the portion where the host 251 and the second guide portion 220 contact each other. Incident on the wavelength converters 250. Accordingly, the path of the light incident on the second guide part 220 may be changed, and at the same time, the wavelength may be converted, reflected on the reflective sheet 300, and emitted upward.

The liquid crystal display according to the embodiment does not separately form an optical path conversion unit, and thus can be easily manufactured.

6 is a cross-sectional view showing a cross section of the light guide member according to the third embodiment. In the description of the present embodiment, reference is made to the description of the foregoing embodiments. That is, the foregoing description of the liquid crystal display devices may be essentially combined with the description of the present liquid crystal display device, except for the changed part.

Referring to FIG. 6, a filling layer 260 may be interposed between the first guide part 210 and the second guide part 220. The filling layer 260 may be entirely filled between the first guide part 210 and the second guide part 220. The filling layer 260 may surround the wavelength converters 250. The filling layer 260 may be entirely disposed around the wavelength converters 250.

The filling layer 260 may have a lower refractive index than the first guide portion 210 and the second guide portion 220. Accordingly, the light incident on the first guide part 210 may be totally reflected at the interface between the first guide part 210 and the filling layer 260. In addition, light incident on the second guide part 220 may be totally reflected as well.

In addition, the filling layer 260 is adhered to the first guide portion 210 and the second guide portion 220. In more detail, the filling layer 260 may be in close contact with the upper surface of the first guide portion 210 and the lower surface of the second guide portion 220.

The filling layer 260 may effectively seal the wavelength converters 250. Accordingly, the light guide member 200 according to the embodiment may have improved reliability and durability.

7 is a cross-sectional view showing a cross section of the light guide member according to the fourth embodiment. 8 is a cross-sectional view showing a cross section of the light guide member according to the fifth embodiment. In the description of the present embodiment, reference is made to the description of the foregoing embodiments. That is, the foregoing description of the liquid crystal display devices may be essentially combined with the description of the present liquid crystal display device, except for the changed part.

Referring to FIG. 7, the first guide part 210 and the second guide part 220 may be bonded to each other. In more detail, the first guide portion 210 and the second guide portion 220 may be in direct contact with each other. In addition, the first guide part 210 and the second guide part 220 may be bonded to each other with the wavelength converters 250 therebetween.

Accordingly, the wavelength converters 250 may have a structure pressed by the first guide part 210 and the second guide part 220.

In addition, referring to FIG. 8, the wavelength converters 250 may be disposed inside the grooves 211 formed in the first guide part 210, respectively. In this case, first optical path changing parts 230 may be formed on the inner surfaces of the grooves 211.

Alternatively, the wavelength converters 250 may be disposed inside the grooves formed in the second guide part 220, respectively. In this case, second optical path changing parts 240 may be formed on inner surfaces of the grooves.

Similarly, in the present embodiment, the first guide portion 210 and the second guide portion 220 are bonded to each other. The first guide part 210 and the second guide part 220 may be bonded to each other by heat or the like.

As such, in the present embodiments, since the first guide part 210 and the second guide part 220 are bonded to each other, the wavelength conversion parts 250 may be effectively sealed. Therefore, the light guide member 200 and the display device including the same may have improved reliability and durability.

9 is a cross-sectional view showing one cross section of the light guide member according to the sixth embodiment. In the description of the present embodiment, reference is made to the description of the foregoing embodiments. That is, the foregoing description of the liquid crystal display devices may be essentially combined with the description of the present liquid crystal display device, except for the changed part.

Referring to FIG. 9, each of the first optical path changing units 230 includes a plurality of first scattering particles 231. The first scattering particles 231 are disposed corresponding to the wavelength converters 250. The first scattering particles 231 are disposed adjacent to the wavelength converters 250.

In addition, the second light path changing units 240 each include a plurality of second scattering particles 241. The second scattering particles 241 are disposed corresponding to the wavelength converters 250. That is, the second scattering particles 241 are disposed adjacent to the wavelength converters 250.

The first scattering particles 231 and the second scattering particles 241 are particles having a refractive index different from that of the first guide part 210 and the second guide part 220. Examples of the material used as the first scattering particles 231 and the second scattering particles 241 may include titanium oxide or aluminum oxide.

In addition, the features, structures, effects and the like described in the embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, and the like illustrated in each embodiment may be combined or modified with respect to other embodiments by those skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims (16)

A light guide member;
A light source disposed on a side of the light guide member; And
A display panel disposed on the light guide member;
The light guide member is
A first guide part disposed under the display panel;
A second guide part disposed on the first guide part; And
The first guide part; And a plurality of wavelength converters interposed between the second guide parts. The display device of claim 1, wherein the first guide portion or the second guide portion includes a plurality of light path changing portions respectively corresponding to the wavelength converters. The display device of claim 2, wherein the optical path changing parts are disposed on an upper surface of the first guide part or a lower surface of the second guide part. The display device of claim 2, wherein an interval between the wavelength converters is narrower as the distance between the wavelength converters increases. The method of claim 1, wherein the wavelength converter
A host in contact with the first guide part and the second guide part; And
And a plurality of wavelength converting particles disposed in the host. The display device of claim 5, wherein the refractive index of the host is equal to or larger than the refractive index of the first guide portion and the refractive index of the second guide portion. The display device of claim 1, wherein the light source enters light through a side surface of the first guide portion and a side surface of the second guide portion. The display device of claim 1, further comprising a filling layer interposed between the first guide part and the second guide part and having a lower refractive index than the first guide part and the second guide part. Display panel;
A wavelength conversion guide member disposed under the display panel; And
It includes a light source for injecting light to the side of the wavelength conversion guide member,
The wavelength conversion guide member
A plurality of wavelength converters for converting wavelengths of light incident through the side surface;
A first guide part disposed under the wavelength conversion parts and configured to guide light incident through the side surface to the wavelength conversion parts; And
And a second guide part disposed on the wavelength conversion parts and configured to guide light incident through the side surface to the wavelength conversion parts. The display device of claim 9, wherein the first guide portion and the second guide portion are bonded to each other. The method of claim 9, wherein a plurality of grooves are formed in the upper surface of the first guide portion,
The wavelength conversion units are disposed in the grooves, respectively. The method of claim 9, wherein a plurality of grooves are formed in the lower surface of the second guide portion,
The wavelength conversion units are disposed in the grooves, respectively. The display device of claim 9, further comprising a plurality of light path changing parts disposed corresponding to the wavelength converters, respectively. The display device of claim 13, wherein the light path changing parts include a scattering pattern or a plurality of scattering particles. The display device of claim 9, further comprising a reflective film disposed on side surfaces of the first guide part and the second guide part. A first guide part;
A second guide part disposed on the first guide part;
A plurality of wavelength converters interposed between the first guide part and the second guide part; And
And a plurality of light path changing parts disposed adjacent to the wavelength converters, respectively.

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