KR20130044032A - Optical member and display device having the same - Google Patents

Abstract

PURPOSE: An optical member and a display device having the same are provided to improve the efficiency of the light emitted from wavelength conversion particles and a light source. CONSTITUTION: A lower substrate(510) is arranged under a wavelength conversion layer(530). An upper substrate(520) is arranged on the wavelength conversion layer. First wave length conversion particles(532) change the wavelength of the light emitted from light emitting diodes. Conductive nanowires(534) are arranged between the first wave length conversion particles. The diameters of the conductive wires are 30 to 12 nm.

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.

Among display devices, there is a device that requires a backlight unit capable of generating light in order to display an image. The backlight unit is a device for supplying light to a display panel including a liquid crystal or the like and includes a light emitting device and means for effectively transmitting the light output from the light emitting device to the liquid crystal side.

As a light source of such a display device, a light emitting diode (LED) or the like may be applied. In addition, in order to effectively transmit the light output from the light source to the display panel side, a light guide plate, an optical sheet, or the like may be stacked and used.

In this case, an optical member or the like that changes the wavelength of light generated from the light source and injects white light into the light guide plate or the display panel may be applied to the display device. In particular, in order to change the wavelength of light, quantum dots or the like can be used.

Quantum dots have a particle size of 10 nm or less and have unique electro-optic properties depending on their size. For example, when the approximate size is 55 to 65 Å, it can emit red, 40 to 50 Å to green, and 20 to 35 Å to blue. Yellow has medium size of red and green quantum dots. As the spectrum of light changes from red to blue, the size of the quantum dots varies from 65 Å to 20 Å, which may be slightly different.

In order to form the optical member including the quantum dots, quantum dots emitting RGB or RYGB, which are three primary colors of light, may be formed by spin coating or printing a transparent substrate such as glass. In this case, when the quantum dot emitting yellow (Y) is further included, white light closer to natural light may be obtained. The matrix (medium) in which the quantum dots are dispersed can apply an inorganic substance or a polymer having excellent transmittance with respect to light in the visible light region and the ultraviolet region (including Far UV) or in the visible light region. For example, it may be inorganic silica, polymethylmethacrylate (PMMA), polydimethylsiloxane (PDMS), poly lactic acid (PLA), silicon polymer or YAG.

A display device to which such quantum dots are applied is disclosed in Korean Patent Laid-Open Publication No. 10-2011-0012246.

Embodiments provide an optical member having an improved performance and a display device including the same.

Optical member according to the embodiment is a host; A plurality of wavelength converting particles disposed in the host; And a plurality of conductive wires disposed in the host.

A display device according to an embodiment includes a light source; A light conversion member to which light emitted from the light source is incident; And a display panel on which light emitted from the light conversion member is incident, wherein the light conversion member comprises a host; A plurality of wavelength converting particles disposed in the host; And a plurality of conductive wires disposed in the host.

The optical member according to the embodiment includes the conductive nanowires. The diameter of the conductive wires may be about 30 nm to about 120 nm. Accordingly, surface plasmon resonance may occur on the surfaces of the conductive wires.

Accordingly, the efficiency of the light emitted from the light source and the light emitted from the wavelength conversion particles can be improved.

In addition, some of the electrons formed by the light incident on the wavelength conversion particles are temporarily received in the conductive wires, and then supplied to the wavelength conversion particles. As such, by the supplied electrons, the wavelength conversion particles emit light again.

Accordingly, the optical member and the display device according to the embodiment can maximize the optoelectronic effect and improve the light efficiency. In addition, the light excited by the incident light goes down to the ground state through several steps. In particular, the conductive wires have an extended shape and may have a length of about 10 μm to about 70 μm. Accordingly, the conductive wires can efficiently receive electrons from the wavelength converting particles and effectively transfer the electrons to other wavelength converting particles.

The optical member and the display device according to the embodiment may improve color reproduction rate and increase color reproduction persistence. Accordingly, the rate of change of color coordinates can be reduced. Therefore, the optical member and the display device according to the embodiment may improve the wavelength conversion efficiency and have improved optical characteristics.

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 according to the first embodiment.
FIG. 3 is a cross-sectional view taken along the line AA ′ of FIG. 2.
4 and 5 illustrate a process of manufacturing the light conversion member according to the first embodiment.
6 is an exploded perspective view illustrating a liquid crystal display according to a second embodiment.
7 is a perspective view showing a light conversion member according to the second embodiment.
FIG. 8 is a cross-sectional view taken along the line BB ′ of FIG. 7.
9 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.
10 to 12 are views illustrating a process of forming the light conversion member according to the second embodiment.
13 is an exploded perspective view showing a liquid crystal display according to a third embodiment.
14 is a perspective view showing a light conversion member according to the third embodiment.
FIG. 15 is a cross-sectional view illustrating a cross section taken along CC ′ in FIG. 14.
16 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 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 according to the first embodiment. FIG. 3 is a cross-sectional view taken along the line A-A 'of FIG. 2. 4 and 5 illustrate a process of manufacturing the light conversion member according to the first embodiment.

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 light source, for example, a plurality of light emitting diodes 400, a printed circuit board 401, and a plurality of optical sheets. Field 500.

The bottom cover 100 has a shape in which an upper portion thereof is opened. 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 improve characteristics of light emitted from the upper surface of the light guide plate 200 to supply the light to the liquid crystal panel 20.

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

The light conversion member 501 may be disposed on an optical path between the light source 300 and the liquid crystal panel 20. For example, the light conversion member 501 may be disposed on the light guide plate 200. In more detail, the light conversion member 501 may be interposed between the diffusion sheet 502 and the light conversion member 501. The light conversion member 501 can convert the wavelength of the incident light and emit the light upward.

For example, when the light emitting diodes 400 are blue light emitting diodes, the light conversion member 501 may convert blue light emitted upward from the light guide plate 200 into green light and red light. That is, the photo-conversion member 501 converts part of the blue light into green light having a wavelength range of about 520 nm to about 560 nm, and converts the other part of the blue light to a light having a wavelength range of about 630 nm to about 660 nm It can be converted into red light.

Accordingly, light passing through the light conversion member 501 without conversion and light converted by the light conversion member 501 can 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.

That is, the photo-conversion member 501 is an optical member that converts the characteristics of the incident light. The photo-conversion member 501 has a sheet shape. That is, the photo-conversion member 501 may be an optical sheet.

As illustrated in FIGS. 2 and 3, the light conversion member 501 includes a lower substrate 510, an upper substrate 520, a wavelength conversion layer 530, and a sealing unit 540.

The lower substrate 510 is disposed under the wavelength conversion layer 530. The lower substrate 510 is transparent and flexible. The lower substrate 510 may be in close contact with the lower surface of the wavelength 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 wavelength conversion layer 530. The upper substrate 520 is transparent and flexible. The upper substrate 520 may be in close contact with the upper surface of the wavelength conversion layer 530.

Examples of the material used as the upper substrate 520 may include a transparent polymer such as polyethylene terephthalate.

The lower substrate 510 and the upper substrate 520 sandwich the wavelength conversion layer 530. The lower substrate 510 and the upper substrate 520 support the wavelength conversion layer 530. The lower substrate 510 and the upper substrate 520 protect the wavelength conversion layer 530 from external physical impacts. The lower substrate 510 and the upper substrate 520 may be in direct contact with the wavelength conversion layer 530.

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 can protect the wavelength conversion layer 530 from external chemical impacts such as moisture and / or oxygen.

The wavelength conversion layer 530 is interposed between the lower substrate 510 and the upper substrate 520. The wavelength 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 wavelength conversion layer 530 includes a host 531, a plurality of first wavelength converting particles 532, a plurality of second wavelength converting particles 533, a plurality of conductive nanowires 534, and a plurality of powders. Acidic enhancing particles 535.

The host 531 surrounds the first wavelength converting particles 532, the second wavelength converting particles 533, the conductive nanowires 534, and the dispersibility enhancing particles 535. That is, the host 531 uniforms the first wavelength converting particles 532, the second wavelength converting particles 533, the conductive nanowires 534, and the dispersibility enhancing particles 535. Disperse inside. The host 531 may be made of a polymer such as a silicone resin. The host 531 is transparent. That is, the host 531 may be formed of a transparent polymer.

The host 531 is disposed between the lower substrate 510 and the upper substrate 520. The host 531 may be in close contact with an upper surface of the lower substrate 510 and a lower surface of the upper substrate 520.

The first wavelength converting particles 532 are disposed between the lower substrate 510 and the upper substrate 520. In more detail, the first wavelength conversion particles 532 may be uniformly dispersed in the host 531, and the host 531 may be disposed between the lower substrate 510 and the upper substrate 520. . The first wavelength conversion particles 532 may be dispersed in the host 531 at a concentration of about 0.5 wt% to about 5 wt%.

The first wavelength converting particles 532 convert the wavelength of light emitted from the light emitting diodes 400. The first wavelength converting particles 532 receive light emitted from the light emitting diodes 400 to convert wavelengths. For example, the first wavelength conversion particles 532 may convert blue light emitted from the light emitting diodes 400 into red light. That is, the first wavelength conversion particles 532 may convert the blue light into red light having a wavelength band between about 630 nm and about 660 nm. Alternatively, the first wavelength conversion particles 532 may convert light emitted from the light emitting diode into green light. That is, the first wavelength conversion particles 532 may convert light emitted from the light emitting diode into green light having a wavelength band of about 500 nm to about 600 nm.

The first wavelength converting particles 532 include a compound semiconductor. In more detail, the first wavelength conversion particles 532 may be nanoparticles including a compound semiconductor. In more detail, the first wavelength conversion particles 532 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 15 nm. In more detail, the diameter of the quantum dot may be about 8 nm to about 11 nm.

The wavelength of the light emitted from the quantum dot can be adjusted according to the size of the quantum dot. 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 more detail, the first wavelength converting particles 532 may be a quantum dot for converting blue light into red light.

The second wavelength converting particles 533 are disposed in the host 531. In more detail, the second wavelength conversion particles 533 may be uniformly dispersed in the host 531.

The second wavelength conversion particles 533 may have a larger diameter than the first wavelength conversion particles 532. In more detail, the diameters of the second wavelength conversion particles 533 may be about 0.5 μm to about 10 μm.

The second wavelength conversion particles 533 convert the wavelength of the light emitted from the light emitting diodes 400. The second wavelength converting particles 533 receive light emitted from the light emitting diodes 400 to convert wavelengths. For example, the second wavelength conversion particles 533 may convert blue light emitted from the light emitting diodes 400 into green light. That is, the second wavelength conversion particles 533 may convert the blue light into green light having a wavelength band between about 500 nm and about 600 nm. Alternatively, the second wavelength converting particles 533 may convert light from the light emitting diode into red light.

That is, when the first wavelength conversion particles 532 convert incident light into red light, the second wavelength conversion particles 533 may convert incident light into green light. On the contrary, when the first wavelength converting particles 532 convert incident light into green light, the second wavelength converting particles 533 may convert incident light into red light.

Phosphor may be used as the second wavelength conversion particles 533. As the second wavelength conversion particles 533, a green phosphor may be used. More specifically, examples of the green phosphor include manganese doped zinc silicon oxide based phosphors (eg, Zn 2 SiO 4: Mn), europium doped strontium gallium sulfide based phosphors (eg, SrGa 2 S 4: Eu) or europium doped. Barium silicon oxide chloride type fluorescent substance (for example, Ba5Si2O7Cl4: Eu) etc. are mentioned.

The second wavelength conversion particles 533 may be a red phosphor. For example, examples of the red phosphor include praseodymium or aluminum-doped strontium titanium oxide-based phosphors (eg, SrTiO 3: Pr, Al) or praseodymium-doped calcium titanium oxide-based phosphors (eg, CaTiO 3: Pr) Etc. can be mentioned.

Alternatively, both of the first wavelength converting particles 532 and the second wavelength converting particles 533 may be quantum dots.

Alternatively, both the first wavelength converting particles 532 and the second wavelength converting particles 533 may be phosphors.

The conductive nanowires 534 is disposed in the host 531. In more detail, the conductive nanowires 534 are uniformly disposed in the host 531. Accordingly, the conductive nanowires 534 are disposed between the first wavelength converting particles 532. In more detail, the conductive nanowires 534 may be adjacent to the first wavelength conversion particles 532.

The conductive nano wires 534 may have an extended shape. An aspect ratio of the conductive nanowires 534 may be about 100 to about 500. The conductive nanowires 534 may have a diameter of about 30 nm to about 120 nm. In more detail, the diameter of the conductive nanowires 534 may be about 40 nm to about 60 nm. The conductive nanowires 534 may have a length of about 10 μm to about 70 μm. In more detail, the conductive nano wires 534 may have a length of about 40 μm to about 60 μm.

The conductive nanowires 534 is a conductor. The conductive nanowires 534 includes a metal. More specifically, examples of the material used for the conductive nanowires 534 include metals such as silver, gold, platinum, palladium, and the like.

The conductive nanowires 534 may be included in the host 531 at a rate of about 0.5 wt% to about 5 wt%.

The dispersibility enhancing particles 535 are disposed in the host 531. The dispersibility enhancing particles 535 may be uniformly dispersed in the host 531. The dispersibility enhancing particles 535 may be uniformly dispersed between the first wavelength converting particles 532 and the second wavelength converting particles 533.

The dispersibility enhancing particles 535 may be transparent. The dispersibility enhancing particles 535 may include an inorganic material. More specifically, examples of the material used as the dispersibility enhancing particles 535 include an oxide such as silicon oxide. For example, silica particles may be used as the dispersibility enhancing particles 535.

The dispersibility enhancing particles 535 may have a diameter of about 10 nm to about 10 μm. In addition, the dispersibility enhancing particles 535 may be included in the host 531 at a rate of about 0.5 wt% to about 5 wt%.

The dispersibility enhancing particles 535 may function to improve dispersibility of the first wavelength converting particles 532 and the second wavelength converting particles 533 in the host 531. . In addition, the dispersibility enhancing particles 535 may perform a scattering particle function of changing a path of incident light.

The light conversion member 501 may be formed by the following process.

Referring to FIG. 4, the plurality of second wavelength converting particles 533 and the plurality of conductive nanowires 534 are uniformly dispersed in a silicone resin, an epoxy resin, or an acrylic resin. In this case, the second wavelength conversion particles 533 may be dispersed by ultrasonic dispersion. That is, ultrasonic waves are applied to the second wavelength converting particles 533 so that the second wavelength converting particles 533 may be pulverized to have a small diameter.

In this case, since the second wavelength converting particles 533 include a phosphor, even if the second wavelength conversion particles 533 are vigorously dispersed, such as ultrasonic dispersion, their own performance is not deteriorated. That is, in a situation where the first wavelength converting particles 532 are not included, the second wavelength converting particles 533 may first be dispersed in a vigorous method.

Thereafter, the dispersibility enhancing particles 535 are added to the resin composition in which the second wavelength conversion particles 533 are dispersed. The dispersibility enhancing particles 535 may increase the viscosity of the resin composition. Accordingly, the dispersibility enhancing particles 535 may prevent the second wavelength converting particles 533 from aggregation again. That is, the dispersibility enhancing particles 535 may function to maintain dispersibility of the second wavelength converting particles 533 and the conductive nanowires 534.

The dispersibility enhancing particles 535 may be added to the resin composition at a rate of about 0.5 wt% to about 5 wt%.

Thereafter, the first wavelength conversion particles 532 are added to the resin composition. The first wavelength converting particles 532 may be dispersed in the resin composition by a less intense method than the second wavelength converting particles 533.

Thereafter, referring to FIG. 5, the resin composition is uniformly coated on the lower substrate 510. The resin composition may be coated on the upper surface of the lower substrate 510 by slit coating, spin coating or spray coating.

Thereafter, after the second wavelength conversion particles 533 are precipitated, the coated resin composition is cured by light and / or heat, and a wavelength conversion layer is formed.

Thereafter, the upper substrate 520 is laminated on the wavelength conversion layer 530, and a sealing part is formed. Accordingly, the light conversion member 501 may be formed.

The sealing part 540 is disposed on the side of the wavelength conversion layer 530. In more detail, the sealing part 540 covers the side surface of the wavelength conversion layer 530. In more detail, the sealing part 540 is also disposed on side surfaces of the lower substrate 510 and the upper substrate 520. In more detail, the sealing part 540 covers side surfaces of the lower substrate 510 and the upper substrate 520.

In addition, the sealing part 540 may be attached to side surfaces of the wavelength conversion layer 530, the lower substrate 510, and the upper substrate 520. The sealing part 540 is in close contact with side surfaces of the wavelength conversion layer 530, the lower substrate 510, and the upper substrate 520.

Accordingly, the sealing part 540 may seal the side surface of the wavelength conversion layer 530. That is, the sealing part 540 is a protection part that protects the wavelength conversion layer 530 from external chemical shock.

In addition, the light conversion member 501 may further include a first inorganic protective film and a second inorganic protective film. The first inorganic protective layer may be coated on the lower surface of the lower substrate 510, and the second inorganic protective layer may be coated on the upper surface of the upper substrate 520. Examples of the material used for the first inorganic protective film and the second inorganic protective film include silicon oxide and the like.

The diffusion sheet 502 is disposed on the light conversion member 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. 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 described above, the light conversion member 501 includes the conductive nanowires 534. In this case, the diameters of the conductive nanowires 534 may be about 30 nm to about 120 nm. Accordingly, surface plasmon resonance may occur on the surfaces of the conductive nanowires 534.

Accordingly, the efficiency of the light emitted from the light source 400 and the light emitted from the wavelength conversion particles 532 and 533 may be improved.

In addition, in order to improve light efficiency due to surface plasmon resonance, a plurality of conductive nanoparticles may be included in the light conversion member 501. That is, when the conductive nanoparticles having a spherical shape or the like are included in the light conversion member 501, the optical properties of the light conversion member 501 may be improved.

The conductive nanoparticles may be uniformly dispersed in the host 531. In addition, the diameter of the conductive nanoparticles may be about 30nm to about 120nm.

Examples of the material used as the conductive nanoparticles may be the same as the metal used as the conductive nanowires 534.

In addition, some of the electrons formed by light incident on the first wavelength converting particles 532 are temporarily accommodated in the conductive nanowires 534 and then supplied to the first wavelength converting particles 534 again. . As such, by the supplied electrons, the wavelength conversion particles emit light again.

Accordingly, the optical member and the display device according to the embodiment can maximize the optoelectronic effect and improve the light efficiency. In addition, the light excited by the incident light goes down to the ground state through several steps. In particular, the conductive nanowires 534 may have an extended shape and have a length of about 10 μm to about 70 μm. Accordingly, the conductive nanowires 534 may efficiently receive electrons from the first wavelength converting particles 532 and effectively transfer the electrons to other first wavelength converting particles. Accordingly, the conductive nanowires 534 may reduce electrons lost without using wavelength conversion and maximize conversion efficiency of the first wavelength conversion particles 532.

The liquid crystal display according to the embodiment may improve color reproduction rate and increase color reproduction persistence. Accordingly, the rate of change of color coordinates can be reduced. Therefore, the liquid crystal display according to the embodiment may improve the wavelength conversion efficiency and have improved optical characteristics.

6 is an exploded perspective view illustrating a liquid crystal display according to a second embodiment. 7 is a perspective view showing a light conversion member according to the second embodiment. FIG. 8 is a cross-sectional view taken along the line BB ′ in FIG. 7. 9 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. 10 to 12 are views illustrating a process of forming 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.

6 to 9, 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.

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. 7 to 9, the light conversion member 600 includes a lower substrate 610, an upper substrate 620, a wavelength conversion layer 630, and a sealing unit 640.

As shown in FIG. 8, the lower substrate 610 is disposed under the wavelength 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 wavelength conversion layer 630.

The upper substrate 620 is disposed on the wavelength 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 wavelength conversion layer 630.

In addition, as shown in FIG. 9, 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 wavelength conversion layer 630. In addition, the upper substrate 620 faces the light guide plate 200. That is, the upper substrate 620 is interposed between the wavelength conversion layer 630 and the light guide plate 200.

The lower substrate 610 and the upper substrate 620 sandwich the wavelength conversion layer 630. In addition, the sealing part 640 covers the side surface of the wavelength conversion layer 630. The lower substrate 610 and the upper substrate 620 support the wavelength conversion layer 630. In addition, the lower substrate 610, the upper substrate 620, and the sealing part 640 protect the wavelength conversion layer 630 from external physical shocks and chemical shocks.

The light conversion member according to the present embodiment may be formed by the following process.

10, a plurality of first wavelength converting particles 632, a plurality of second wavelength converting particles 633, a plurality of conductive nanoparticles 634, and a plurality of first wavelength converting particles 611 on a first transparent substrate 611. A resin composition comprising two dispersibility enhancing particles 535 is coated. Thereafter, the resin composition is cured by light and / or heat of the resin composition, and a preliminary wavelength conversion layer 635 is formed on the first transparent substrate 611.

Thereafter, the second transparent substrate 621 is laminated on the preliminary wavelength conversion layer 635.

Referring to FIG. 11, the first transparent substrate 611, the preliminary wavelength conversion layer 635, and the second transparent substrate 621 are cut at a time. Accordingly, a plurality of preliminary light conversion members 601 are formed. The preliminary light conversion members 601 include a lower substrate 610, a wavelength conversion layer 630, and an upper substrate 620, respectively. In this case, since the lower substrate 610, the wavelength conversion layer 630 and the upper substrate 620 are formed by the same cutting process, the lower substrate 610, the wavelength conversion layer 630 and the upper substrate 620 includes a cut surface 605 disposed on the same plane.

Referring to FIG. 12, the preliminary light conversion members 601 are aligned with each other such that the lower substrate 610 and the upper substrate 620 face each other. Thereafter, a sealing part 640 is formed on the side surfaces of the preliminary light conversion members 601, that is, the cut surface 605.

Thereafter, the light conversion members 600 may be separated from each other.

In the liquid crystal display according to the present embodiment, the wavelength conversion layer 630 has a relatively small size. Therefore, in manufacturing the liquid crystal display according to the present embodiment, a small amount of the first wavelength converting particles 632 and the second wavelength converting particles 633 may be used.

Therefore, the liquid crystal display according to the present exemplary embodiment can reduce the use of the first wavelength converting particles 631 and the second wavelength converting particles 533 and can be easily manufactured at low cost.

13 is an exploded perspective view showing a liquid crystal display according to a third embodiment. 14 is a perspective view showing a light conversion member according to the third embodiment. FIG. 15 is a cross-sectional view taken along the line CC ′ in FIG. 14. 16 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 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.

13 to 16, 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.

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.

13 to 16, the light conversion members 700 include a lower substrate 710, an upper substrate 720, a wavelength conversion layer 730, and a sealing unit 640.

Features of the lower substrate 710, the upper substrate 720, the wavelength conversion layer 730, and the sealing unit 640 may be substantially the same as those described in the above-described embodiments.

In the liquid crystal display according to the present embodiment, the wavelength conversion layer 730 has a relatively small size. Therefore, in manufacturing the liquid crystal display according to the present embodiment, a small amount of the first wavelength converting particles 732 and the second wavelength converting particles 733 may be used.

Therefore, the liquid crystal display according to the present exemplary embodiment can reduce the use of the first wavelength converting particles 432 and the second wavelength converting particles 733 and can be easily manufactured at low cost.

In addition, the characteristics of each light conversion member 700 may be modified to suit the corresponding light emitting diode 400. Accordingly, the liquid crystal display according to the embodiment may have improved reliability, brightness, and uniform color reproduction.

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 (10)

Host;
A plurality of wavelength converting particles disposed in the host; And
An optical member comprising a plurality of conductive wires disposed within the host. The optical member of claim 1, wherein the conductive wires comprise a metal. The optical member of claim 1, wherein the conductive wires comprise silver. The method of claim 1, wherein the diameter of the conductive wires is 30nm to 120nm,
The length of the conductive wires is 10㎛ 70㎛ optical member. The optical member of claim 1, wherein the conductive wires are disposed in the host at a rate of 0.5 wt% to 5 wt%. The optical member of claim 1, wherein the wavelength conversion particles include a semiconductor compound. Light source;
A light conversion member to which light emitted from the light source is incident; And
A display panel to which light emitted from the light conversion member is incident;
The light conversion member
Host;
A plurality of wavelength converting particles disposed in the host; And
And a plurality of conductive wires disposed in the host. The method of claim 7, wherein the wavelength conversion particles are
A plurality of first wavelength converting particles comprising a compound semiconductor; And
A display device comprising a plurality of second wavelength converting particles including a phosphor. The method of claim 7, wherein the diameter of the first wavelength conversion particles is 1nm to 50nm,
The diameter of the second wavelength conversion particles is 1㎛ 50㎛ display device. Host;
A plurality of wavelength converting particles disposed in the host; And
An optical member comprising a plurality of conductive particles disposed in the host.

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