KR20130133994A - Optical member, light emitting device and display device - Google Patents

Abstract

An optical member, a light emitting device, and a display device are disclosed. The optical member comprises: a host layer; optical conversion particles arranged inside the host layer; and barrier particles arranged inside the host layer. The barrier particles include silicone-based resin.

Description

OPTICAL MEMBER, LIGHT EMITTING DEVICE AND DISPLAY DEVICE}

Embodiments relate to an optical member, a light emitting device including the same, 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.

In addition, a light emitting device that generates white light using a blue LED and a quantum dot is widely used. In particular, such a light emitting device is also used in automobile headlights or indoor lighting.

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, a light emitting device, and a display device having improved reliability, color reproducibility, and luminance.

In one embodiment, the optical member includes a host layer; A plurality of light conversion particles disposed in the host layer; And a plurality of barrier particles disposed in the host layer, wherein the barrier particles include a silicone-based resin.

In one embodiment, a light emitting device includes: a light source; And a light conversion member to which light from the light source is incident, wherein the light conversion member host layer; A plurality of light conversion particles disposed in the host layer; And a plurality of barrier particles disposed in the host layer, wherein the barrier particles include a silicone-based resin.

A display device according to an embodiment includes a light source; A light conversion member on which light from the light source is incident; And a display panel to which light from the light conversion member is incident, wherein the light conversion member host layer; A plurality of light conversion particles disposed in the host layer; And a plurality of barrier particles disposed in the host layer, wherein the barrier particles include a silicone-based resin.

Barrier particles comprising a silicone-based resin according to the embodiment. The carrier particles may include a silicone-based resin such as polysilsesquioxane. Accordingly, the barrier particles may impart improved barrier properties to the host layer.

Therefore, the light conversion particles may be effectively protected from external oxygen and / or moisture by the barrier particles. Thus, it can have improved reliability and durability according to the embodiment.

In addition, the barrier particles may change the path of incident light in various directions. That is, the barrier particles may perform a light path changing function. Accordingly, the barrier particles may increase the path of light in the host layer.

Therefore, by the barrier particles, the light conversion particles can effectively convert the incident light. Therefore, the optical member, the light emitting device, and the display device according to the embodiment may have improved luminance and color reproducibility.

1 is an exploded perspective view of a liquid crystal display according to a first embodiment.
2 is a perspective view showing a light conversion member.
FIG. 3 is a cross-sectional view showing a section cut along AA 'in FIG. 2. FIG.
4 is an exploded perspective view showing a liquid crystal display according to a second embodiment.
5 is a perspective view showing a light conversion member according to the second embodiment.
FIG. 6 is a cross-sectional view taken along the line BB ′ of FIG. 5.
7 is a cross-sectional view illustrating a cross section of the light guide plate, the light emitting diode, and the light conversion member according to the second embodiment.
8 is an exploded perspective view showing a liquid crystal display according to a third embodiment.
9 is a perspective view showing a light conversion member according to the third embodiment.
FIG. 10 is a cross-sectional view illustrating a cross section taken along CC ′ in FIG. 9.
11 is a cross-sectional view illustrating a light guide plate, a light emitting diode, and a light conversion member according to a third 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 a perspective view showing a light conversion member. FIG. 3 is a cross-sectional view taken along the line A-A 'of FIG. 2.

1 to 3, 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 light guide plate 200, a reflective sheet 300, a plurality of light emitting diodes 400, a printed circuit board 401, and a plurality of optical sheets 500. do.

The bottom cover 100 has a top opened shape. The bottom cover 100 accommodates the light guide plate 200, the light emitting diodes 400, the printed circuit board 401, the reflective sheet 300, and the optical sheets 500.

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

The reflective sheet 300 is disposed below the light guide plate 200. In more detail, the reflective sheet 300 is disposed between the light guide plate 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 plate 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 plate 200. The light emitting diodes 400 generate light and enter the light guide plate 200 through a side surface of the light guide plate 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 optical sheets 500 are disposed on the light guide plate 200. The optical sheets 500 change or enhance the characteristics of light emitted from the upper surface of the light guide plate 200 and supply the light to the liquid crystal panel 20. [

The optical sheets 500 may be a light conversion sheet 501, a diffusion sheet 502, a first prism sheet 503, and a second prism sheet 504.

The light conversion sheet 501 is disposed on the light guide plate 200. In more detail, the light conversion sheet 501 may be interposed between the light guide plate 200 and the diffusion sheet 502. The light conversion sheet 501 may convert the wavelength of the incident light and exit upward.

For example, when the light emitting diodes 400 are blue light emitting diodes, the light conversion sheet 501 may convert blue light emitted upward from the light guide plate 200 into green light and red light. That is, the light conversion sheet 501 converts a part of the blue light into green light having a wavelength band of about 520 nm to about 560 nm, and another part of the blue light having a wavelength band of about 630 nm to about 660 nm. Can be converted to red light.

In addition, when the light emitting diodes 400 are UV light emitting diodes, the light conversion sheet 501 may convert ultraviolet light emitted from the upper surface of the light guide plate 200 into blue light, green light, and red light. That is, the light conversion sheet 501 converts a part of the ultraviolet light into blue light having a wavelength band between about 430 nm and about 470 nm, and another part of the ultraviolet light has a wavelength band between about 520 nm and about 560 nm. Green light, and another portion of the ultraviolet light to red light having a wavelength band between about 630 nm and about 660 nm.

Accordingly, the light that is not converted and passes through the light conversion sheet 501 and the light converted by the light conversion sheet 501 may form white light. That is, the blue light, the green light, and the red light may be combined, and the white light may be incident on the liquid crystal panel 20.

The light conversion sheet 501 corresponds to a light conversion member for converting the wavelength of incident light. That is, the light conversion sheet 501 is an optical member that changes the characteristics of incident light.

As shown in FIGS. 2 and 3, the light conversion sheet 501 includes a lower substrate 510, an upper substrate 520, and a light conversion layer 530.

The lower substrate 510 is disposed under the light conversion layer 530. The lower substrate 510 is transparent and flexible. The lower substrate 510 may be in close contact with the bottom surface of the light conversion layer 530.

Examples of the material used for the lower substrate 510 include transparent polymers such as polyethylene terephthalate (PET) and the like.

The upper substrate 520 is disposed on the light conversion layer 530. The upper substrate 520 is transparent and flexible. The upper substrate 520 may be in close contact with the top surface of the light conversion layer 530.

Examples of materials used for the upper substrate 520 include transparent polymers such as polyethylene terephthalate.

The lower substrate 510 and the upper substrate 520 sandwich the light conversion layer 530. The lower substrate 510 and the upper substrate 520 support the light conversion layer 530. The lower substrate 510 and the upper substrate 520 protect the light conversion layer 530 from an external physical shock.

In addition, the lower substrate 510 and the upper substrate 520 have low oxygen permeability and moisture permeability. Accordingly, the lower substrate 510 and the upper substrate 520 may protect the light conversion layer 530 from external chemical impact such as moisture and / or oxygen.

The light conversion layer 530 is interposed between the lower substrate 510 and the upper substrate 520. The light conversion layer 530 may be in close contact with the upper surface of the lower substrate 510, and may be in close contact with the lower surface of the upper substrate 520. The light conversion layer 530 includes a plurality of light conversion particles 531, a plurality of barrier particles 533, and a host layer 532.

The light conversion particles 531 are disposed between the lower substrate 510 and the upper substrate 520. In more detail, the light conversion particles 531 are uniformly dispersed in the host layer 532, and the host layer 532 is disposed between the lower substrate 510 and the upper substrate 520.

The light conversion particles 531 convert wavelengths of light emitted from the light emitting diodes 400. The light conversion particles 531 receive light emitted from the light emitting diodes 400 to convert wavelengths. For example, the light conversion particles 531 may convert blue light emitted from the light emitting diodes 400 into green light and red light. That is, some of the light conversion particles 531 convert the blue light into green light having a wavelength band between about 520 nm and about 560 nm, and another part of the light conversion particles 531 converts the blue light about 630. It can be converted into red light having a wavelength band between nm and about 660 nm.

Alternatively, the light conversion particles 531 may convert ultraviolet light emitted from the light emitting diodes 400 into blue light, green light, and red light. That is, some of the light conversion particles 531 convert the ultraviolet light into blue light having a wavelength band between about 430 nm and about 470 nm, and another part of the light conversion particles 531 converts the ultraviolet light to about 520. It can be converted into green light having a wavelength band between nm and about 560 nm. In addition, another part of the light conversion particles 531 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 for generating blue light, light conversion particles 531 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, light conversion particles 531 converting ultraviolet rays into blue light, green light, and red light may be used.

The light conversion particles 531 may be a plurality of quantum dots (QDs). The quantum dot may include core nanocrystals and shell nanocrystals surrounding the core nanocrystals. 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.

The barrier particles 533 are disposed in the host layer 532. The barrier particles 533 may be uniformly dispersed in the host layer 532. Alternatively, the barrier particles 533 may be disposed on the outer portion of the host layer 532. In more detail, the barrier particles 533 may be disposed only at an outer portion of the host layer 532.

The barrier particles 533 may have a diameter of about 0.5 μm to about 10 μm. In more detail, the barrier particles 533 may have a diameter of about 1 μm to about 3 μm.

The barrier particles 533 may be included in the host layer 532 at a ratio of about 0.1 wt% to about 10 wt%. In more detail, the barrier particles 533 may be included in the host layer 532 at a rate of about 0.5 wt% to about 3 wt%.

The barrier particles 533 may include a silicone resin. In more detail, the barrier particles 533 may be made of a silicone-based resin. The silicone resin may be selected from siloxane resin or silsesquioxane resin.

In more detail, the siloxane resin may be polysiloxane such as polydimethylsiloxane (PDMS) or the like.

In addition, the silsesquioxane resin may be polysilsesquioxane such as polymethylsilsesquioxane (PMSQ).

In more detail, the silicone resin may be represented by the following Chemical Formula 1.

Formula 1

Wherein R1, R2 and R3 are selected from hydrogen, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted heteroaryl group, halogen, amine group or carboxyl group Can be. The alkyl group may have 1 to 30 carbons. In more detail, the alkyl group may be substituted by halogen or the like. The alkyl group may be selected from methyl group, ethyl group or isopropyl group. In more detail, the alkyl group may be a methyl group. In addition, x may be 1 to 1000. In addition, y may be from 1 to 1000.

In addition, the silicone-based resin may be a polysilsesquioxane in which Formula 1 is repeated. In this case, x and y may be 1 to 5. More specifically, x and y is 1, the silicone resin may have a structure in which the formula (1) is repeated.

In addition, R3 may be represented by the following formula (2).

(2)

Wherein n is 1 to 10 and R4 is hydrogen, substituted or unsubstituted alkyl group, substituted or unsubstituted alkene group, substituted or unsubstituted aryl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted hetero It may be selected from an aryl group, a halogen, an amine group or a carboxyl group. The alkyl group may have 1 to 30 carbons. The alkene group may have 1 to 30 carbons. In more detail, the alkene group may be an ethylene group. In addition, R4 may be fluorine (F) or chlorine (Cl).

In Formula 2, when n = 3 or n = 7, R 4 may be an alkyl group. When n = 1, R 4 may be chlorine. In addition, when n = 2 or n = 6, R4 may be an ethylene group. When n = 7, R 4 may be an aldehyde group.

The polysilsesquioxane may be formed by polymerizing a siloxane-based monomer or oligomer. More specifically, in an organic solvent such as toluene, the polysilsesquioxane can be formed by polymerizing a siloxane oligomer under a titanium catalyst.

The catalyst may be bis (cyclopentadienyl) titanium dichloride (Cp 2 TiCl 2).

Further, the siloxane oligomer may be (R1) ₃ -SiO- [R1-HSiO] _m -Si- (R1) ₃ . In more detail, the siloxane-based oligomer may be Me ₃ -SiO- [R1-HSiO] _m -Si-Me ₃ . Here, m may be 1 to 100. In more detail, the siloxane oligomer may be polymethyhydrosiloxane (PMHS). The polymethylhydrosiloxane may have a molecular weight of about 2000. In addition, the polymethylhydrosiloxane may have a viscosity of 30cts.

The polymerization reaction may be performed at room temperature. In addition, the polymerization reaction may be performed for about 48 hours to about 72 hours.

The polysilsesquioxane thus formed may be substituted with various substituents by a hydrosilylation process.

In more detail, to the polysilsesquioxane formed by the polymerization reaction, a substituted or unsubstituted alkene is added under a platinum catalyst so that a substitution reaction can occur. Here, the alkenes may have 2 to 10 carbons. The polysilsesquioxane formed by the polymerization reaction may have a structure in which R 3 in Formula 1 is H. At this time, CH ₂ = CH (CH ₂ ) _n -R 4 is added to the polysilsesquioxane as described above, and a substitution reaction may occur under a platinum catalyst. Accordingly, the hydrogen of the R3 position may be substituted with a structure as shown in formula (2).

In addition, a crosslinking reaction may occur simultaneously with such a substitution reaction. That is, polysilsesquioxane formed by the polymerization reaction may be crosslinked with each other by the alkene.

The substitution reaction and / or the crosslinking reaction may proceed at about 80 ° C. In addition, the substitution reaction and / or the crosslinking reaction may proceed for about 30 minutes to about 24 hours.

Thereafter, the barrier particles 533 including the silicone resin may be formed through a purification process and a solvent removal process.

The host layer 532 surrounds the light conversion particles 531 and the barrier particles 533. That is, the host layer 532 uniformly disperses the light conversion particles 531 therein. The host layer 532 may be comprised of a polymer. The host layer 532 is transparent. That is, the host layer 532 may be formed of a transparent polymer.

The host layer 532 is disposed between the lower substrate 510 and the upper substrate 520. The host layer 532 may be in close contact with an upper surface of the lower substrate 510 and a lower surface of the upper substrate 520.

The light conversion layer 530 may be formed by the following process. First, the barrier particles 533 and the light conversion particles 531 are uniformly mixed with a resin for forming the host layer 532.

Thereafter, the resin in which the barrier particles 533 and the light conversion particles 531 are uniformly dispersed is uniformly coated on the lower substrate 510 or the upper substrate 520, and cured to form the light conversion. Layer 530 may be formed.

In addition, the light conversion sheet 501 may further include a first inorganic protective film and a second inorganic protective film.

The first inorganic protective layer is disposed under the light conversion layer 530. In more detail, the first inorganic protective layer may be disposed under the lower substrate 510. In more detail, the first inorganic protective layer may be coated on the bottom surface of the lower substrate 510.

The first inorganic protective layer may protect the light conversion layer 530 together with the lower substrate 510. That is, the first inorganic protective layer may protect the light conversion layer 530 from external physical impact. In addition, the first inorganic protective layer may prevent oxygen and / or moisture from penetrating into the light conversion layer 530.

In addition, the first inorganic protective layer may have a lower refractive index than the lower substrate 510. For example, the refractive index of the first inorganic protective layer may be about 1.3 to 1.6.

Accordingly, the first inorganic passivation layer may perform an optical buffer function between the lower substrate 510 and the capping unit 560, thereby reducing reflection on the lower surface of the lower substrate 510.

Examples of the material used as the first inorganic protective film include silicon oxide or silicon nitride.

The second inorganic protective film is disposed on the light conversion layer 530. In more detail, the second inorganic protective layer may be disposed on the upper substrate 520. In more detail, the second inorganic protective layer may be coated on the upper surface of the upper substrate 520.

The second inorganic passivation layer may protect the light conversion layer 530 together with the upper substrate 520. That is, the second inorganic protective film may protect the light conversion layer 530 from external physical impact. In addition, the second inorganic protective film may prevent oxygen and / or moisture from penetrating into the light conversion layer 530.

The second inorganic protective layer may have a lower refractive index than the upper substrate 520. For example, the refractive index of the second inorganic protective layer may be about 1.3 to 1.6.

Accordingly, the second inorganic passivation layer may perform an optical buffering function between the upper substrate 520 and the capping unit 560 to reduce reflection on the upper surface of the upper substrate 520.

Examples of the material used as the second inorganic protective film include silicon oxide or silicon nitride.

The first inorganic protective layer and the second inorganic protective layer not only perform an optical function such as an anti-reflection function, but also seal the light conversion layer 530 to protect from external physical and chemical shocks.

Referring back to FIG. 1, the diffusion sheet 502 is disposed on the light conversion sheet 501. The diffusion sheet 502 improves the uniformity of light passing therethrough. The diffusion sheet 502 may include a plurality of beads.

The first prism sheet 503 is disposed on the diffusion sheet 502. The second prism sheet 504 is disposed on the first prism sheet 503. The first prism sheet 503 and the second prism sheet 504 increase the straightness of light passing therethrough.

The liquid crystal panel 20 is disposed on the optical sheets 500. Further, 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 for displaying an image 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 polarizing filters.

Although not shown in detail in the drawings, the TFT substrate 21 and the color filter substrate 22 will be described in detail. The TFT substrate 21 defines pixels by intersecting a plurality of gate lines and data lines, A thin film transistor (TFT) is provided for each region and is connected in a one-to-one correspondence with the pixel electrodes mounted on the respective pixels. The color filter substrate 22 includes color filters of R, G and B colors corresponding to the respective pixels, a black matrix for covering the gate lines, the data lines, the thin film transistors, etc., .

And a driving PCB 25 for supplying a driving signal to the gate line and the data line is provided at an edge of the liquid crystal display panel 210.

The drive 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 TCP (Tape Carrier Package).

As described above, the light conversion sheet 501 includes the barrier particles 533. In particular, the barrier particle 533 may include a silicone-based resin such as polysilsesquioxane. Accordingly, the barrier particles 533 may impart improved barrier properties to the host layer 532.

Therefore, the light conversion particles 531 may be effectively protected from external oxygen and / or moisture by the barrier particles 533. Thus, it can have improved reliability and durability according to the embodiment.

In addition, the barrier particles 533 may change the path of incident light in various directions. That is, the barrier particles 533 may perform an optical path changing function. Accordingly, the barrier particles 533 may increase the path of light in the host layer 532.

Therefore, the light conversion particles 531 may effectively convert incident light by the barrier particles 533. Therefore, the liquid crystal display according to the embodiment may have improved luminance and color reproducibility.

4 is an exploded perspective view showing a liquid crystal display according to a second embodiment. 5 is a perspective view showing a light conversion member according to the second embodiment. FIG. 6 is a cross-sectional view taken along the line BB ′ in FIG. 5. 7 is a cross-sectional view illustrating a cross section of the light guide plate, the light emitting diode, and the light conversion 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.

4 to 7, the liquid crystal display according to the present exemplary embodiment includes the light conversion member 600 instead of the light conversion sheet 501. The light conversion member 600 is interposed between the light emitting diodes 400 and the light guide plate 200.

The light conversion member 600 may have a shape extending in one direction. In more detail, the light conversion member 600 may have a shape extending along one side surface of the light guide plate 200. In more detail, the light conversion member 600 may have a shape extending along the incident surface of the light guide plate 200.

The light conversion member 600 receives the light emitted from the light emitting diodes 400 and converts the wavelength. For example, the light conversion member 600 may convert blue light emitted from the light emitting diodes 400 into green light and red light. That is, the light conversion member 600 converts a part of the blue light into green light having a wavelength band between about 520 nm and about 560 nm, and another part of the blue light has a wavelength band between about 630 nm and about 660 nm. Can be converted to red light.

In addition, the light conversion member 600 may convert ultraviolet light emitted from the light emitting diodes 400 into blue light, green light, and red light. That is, the light conversion member 600 converts a part of the ultraviolet light into blue light having a wavelength band between about 430 nm and about 470 nm, and another part of the ultraviolet light has a wavelength band between about 520 nm and about 560 nm. Green light, and another portion of the ultraviolet light to red light having a wavelength band between about 630 nm and about 660 nm.

Accordingly, the light passing through the light conversion member 600 and the light converted by the light conversion member 600 may form white light. That is, the blue light, the green light, and the red light may be combined, and the white light may be incident on the light guide plate 200.

As shown in FIGS. 5 to 7, the light conversion member 600 includes a lower substrate 610, an upper substrate 620, and a light conversion layer 630.

As illustrated in FIGS. 5 and 6, the lower substrate 610 is disposed under the light conversion layer 630. The lower substrate 610 may be transparent and flexible. The lower substrate 610 may be in close contact with the bottom surface of the light conversion layer 630.

In addition, as shown in FIG. 7, the lower substrate 610 faces the light emitting diodes 400. That is, the lower substrate 610 is disposed between the light emitting diodes 400 and the light conversion layer 630.

As shown in FIGS. 5 and 6, the upper substrate 620 is disposed on the light conversion layer 630. The upper substrate 620 may be transparent and flexible. The upper substrate 620 may be in close contact with the top surface of the light conversion layer 630.

In addition, as illustrated in FIG. 7, the upper substrate 620 faces the light guide plate 200. That is, the upper substrate 620 is disposed between the light guide plate 200 and the light conversion layer 630.

The light conversion layer 630 is interposed between the lower substrate 610 and the upper substrate 620. The light conversion layer 630 is sandwiched by the lower substrate 610 and the upper substrate 620. The light conversion layer 630 may have substantially the same features as the light conversion layer in the above embodiment. In particular, the light conversion layer 630 includes a plurality of light conversion particles 631 and a plurality of barrier particles 633. The barrier particles 633 may be substantially the same as the barrier particles in the foregoing embodiment.

In the liquid crystal display according to the present embodiment, the light conversion layer 630 has a relatively small size. Therefore, in manufacturing the liquid crystal display according to the present embodiment, a small amount of light conversion particles 631 may be used.

Therefore, the liquid crystal display according to the present embodiment can be manufactured easily and at low cost by reducing the use of the light conversion particles 631.

8 is an exploded perspective view showing a liquid crystal display according to a third embodiment. 9 is a perspective view showing a light conversion member according to the third embodiment. FIG. 10 is a cross-sectional view taken along the line CC ′ in FIG. 9. 11 is a cross-sectional view illustrating a light guide plate, a light emitting diode, and a light conversion member according to a 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.

8 to 11, the liquid crystal display according to the present exemplary embodiment includes a plurality of light conversion members 700. The light conversion members 700 correspond to the light emitting diodes 400, respectively.

In addition, the light conversion members 700 are disposed between the light emitting diodes 400 and the light guide plate 200. That is, each light conversion member 600 is disposed between the corresponding light emitting diode and the light guide plate 200.

In addition, the light conversion members 700 convert the wavelength of light emitted from the corresponding light emitting diode. In this case, the light conversion members 700 convert the light emitted from the light emitting diodes into light of a first wavelength such as green light and second light of the second wavelength such as red light. It can be divided into light conversion members.

The light conversion members 700 may have a larger planar area than the light emitting diodes 400. Accordingly, almost all of the light emitted from each light emitting diode may be incident on the corresponding light conversion member 600.

9 to 11, the light conversion members 700 include a lower substrate 710, an upper substrate 720, and a light conversion layer 730.

Features of the lower substrate 710, the upper substrate 720, and the light conversion layer 730 may be substantially the same as those described in the above-described embodiments.

In the liquid crystal display according to the present embodiment, the light conversion layer 730 has a relatively small size. Therefore, in manufacturing the liquid crystal display according to the present embodiment, a small amount of light conversion particles 731 may be used.

Therefore, the liquid crystal display according to the present embodiment can be manufactured easily and at low cost by reducing the use of the light conversion particles 731.

In addition, the characteristics of each of the light conversion members 700 may be modified to suit the corresponding light emitting diodes. Accordingly, the liquid crystal display according to the embodiment may have improved luminance and uniform color reproduction.

In the above, the embodiments have been focused on the optical member and the display device in which the barrier particles are used, but the present invention is not limited thereto. That is, the light emitting diodes, the light conversion member, and the like in the present embodiment are used, so that the light emitting device used as lighting or automobile headlights can be implemented. That is, light is emitted from a light source such as a light emitting diode or the like, and light is converted from the light source by the light converting member according to the embodiment and emitted. Accordingly, the light emitting device for emitting the desired light can be implemented.

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 the embodiments 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 (12)

Host layer;
A plurality of light conversion particles disposed in the host layer; And
A plurality of barrier particles disposed in the host layer,
The barrier particles include a silicone resin. The optical member according to claim 1, wherein the silicone resin is selected from polysiloxanes. The optical member according to claim 1, wherein the silicone resin is selected from silsesquioxane resin. The optical member according to claim 1, wherein the silicone resin is selected from polysilsesquioxane resin. The optical member of claim 1, wherein the silicone resin is represented by Formula 1 below.
Formula 1

Wherein R1, R2 and R3 are selected from hydrogen, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted heteroaryl group, halogen, amine group or carboxyl group Wherein the alkyl group has 1 to 30 carbons, x is 1 to 1000 and y is 1 to 1000. 4. The optical member according to claim 3, wherein R1 and R2 are methyl groups. The optical member according to claim 1, wherein the silicone resin is polymethylsilsesquioxane. Light source; And
A light conversion member to which light from the light source is incident;
The light conversion member
Host layer;
A plurality of light conversion particles disposed in the host layer; And
A plurality of barrier particles disposed in the host layer,
The barrier particles include a silicon-based resin. The optical member of claim 8, wherein the silicone resin is represented by Formula 1 below.
Formula 1

Wherein R1, R2 and R3 are selected from hydrogen, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted heteroaryl group, halogen, amine group or carboxyl group Wherein the alkyl group has 1 to 30 carbons, x is 1 to 1000 and y is 1 to 1000. Light source;
A light conversion member on which light from the light source is incident; And
And a display panel on which light from the photo-conversion member is incident,
The light conversion member
Host layer;
A plurality of light conversion particles disposed in the host layer; And
A plurality of barrier particles disposed in the host layer,
The barrier particles include a silicone resin. The display device of claim 10, wherein the silicone resin is represented by Formula 1 below.
Formula 1

Wherein R1, R2 and R3 are selected from hydrogen, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted heteroaryl group, halogen, amine group or carboxyl group Wherein the alkyl group has 1 to 30 carbons, x is 1 to 1000 and y is 1 to 1000. The display device of claim 11, wherein R 3 is represented by Formula 2 below.
(2)

Wherein n is 1 to 10 and R4 is hydrogen, substituted or unsubstituted alkyl group, substituted or unsubstituted alkene group, substituted or unsubstituted aryl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted hetero An aryl group, a halogen, an amine group or a carboxyl group, wherein the alkyl group has 1 to 30 carbons and the alkene group has 1 to 30 carbons.

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