KR102135514B1 - Backlight unit and display including the same - Google Patents

Abstract

Light source; A light guide member for guiding light output from the light source; A reflection conversion film disposed under the light guide member; And a diffusion conversion film disposed on the light guide member, wherein the reflection conversion film is a film on which a first wavelength conversion layer including a first wavelength conversion material is stacked and positioned on one surface of a reflection film, and the diffusion The conversion film is a film on which a second wavelength conversion layer including a second wavelength conversion material is stacked and positioned on one surface of a diffusion film, wherein the first wavelength conversion material and the second wavelength conversion material are first quantum dot powder and second. Each of at least one of quantum dot powder, and the reflection conversion film converts a first light equal to a spectrum of light output from the light source, so that a second light having a spectrum different from the first light is directed to the light guide member Output, and the diffusion conversion film converts at least a portion of the first light and the second light to output a third light having a spectrum different from the first light and the second light, and the first light It relates to a backlight unit, wherein the third light is mixed and output.

Description

A backlight unit and a display device including the same {Backlight unit and display including the same}

The following embodiments relate to a backlight unit.

The following embodiments relate to a display device including a backlight unit.

More specifically, the present invention relates to a backlight unit in which a diffusion conversion film and a reflection conversion film are respectively disposed above and below a light guide member and a display device including the same.

Quantum dots refer to ultra-fine semiconductor particles having a size of several nanometers (nm) or less in diameter, and quantum dots emit light of various wavelengths depending on the size of particles, so that various displays, solar cells, computers, etc. It is used in the field.

Currently, in the case of a quantum dot film, the quantum dot solution is implemented and used in a manner supported on a resin in the form of a film. The quantum dot film may be included in a backlight unit and provided in a display device such as a display. Recently, a demand for a backlight unit that is easy to be disposed in a display device has increased.

In addition, the conventional quantum dot film has a problem that the light efficiency of the quantum dot film is reduced over time. Accordingly, there is an increasing demand for a quantum dot film with improved image stability and thermal stability to maintain light efficiency at the time of implementation even in the recent passage of time.

In addition, quantum dots are currently manufactured and sold in solution. However, when the quantum dots are in solution, the quantum dots must be stored at low temperatures. If the quantum dot solution is stored at room temperature, the quantum efficiency of the quantum dot solution is reduced, and there is a problem that the concentration of the quantum dot solution is different due to the vaporization of the solvent. In addition, the secondary processing (film, pellet, etc.) of the quantum dot solution is very difficult, which limits the development of products using quantum dots. In addition, quantum dots are oxidized by oxygen and moisture in the atmosphere, and thus have a characteristic that the luminous efficiency of quantum dots is reduced. Accordingly, there is an increasing demand for quantum dot powders having convenience of storage while maintaining luminous efficiency and concentration of quantum dots.

Embodiments provide a backlight unit in which a diffusion conversion film and a reflection conversion film are respectively disposed on and under a light guide member and a display device including the same.

DETAILED DESCRIPTION Embodiments provide a backlight unit in which a wavelength conversion layer is integrated with a diffusion conversion film and a reflection conversion film, respectively, on a light guide member, and a display device including the same.

DETAILED DESCRIPTION Embodiments provide a backlight unit in which a wavelength conversion layer including a plurality of beads, chain molecules, and quantum dots are integrated, and a backlight unit in which a reflection conversion film is disposed on and under light guide members, respectively, and a display device including the same. .

Embodiments of the plurality of beads, chain molecules and quantum dots are separated by a wavelength conversion layer in which the wavelength conversion layer is separated by an inorganic phosphor, the diffusion conversion film and the reflection conversion film are respectively disposed on the light guide member, the backlight unit respectively And a display device including the same.

The problems to be solved by the present invention are not limited to the above-described problems, and the problems not mentioned will be clearly understood by those skilled in the art from the present specification and the accompanying drawings. .

According to an embodiment of the backlight unit, the light source; A light guide member for guiding light output from the light source; A reflection conversion film disposed under the light guide member; And a diffusion conversion film disposed on the light guide member, wherein the reflection conversion film is a film on which a first wavelength conversion layer including a first wavelength conversion material is stacked and positioned on one surface of a reflection film, and the diffusion The conversion film is a film on which a second wavelength conversion layer including a second wavelength conversion material is stacked and positioned on one surface of a diffusion film, wherein the first wavelength conversion material and the second wavelength conversion material are first quantum dot powder and second. Each of at least one of quantum dot powder, and the reflection conversion film converts a first light equal to a spectrum of light output from the light source, so that a second light having a spectrum different from the first light is directed to the light guide member Output, and the diffusion conversion film converts at least a portion of the first light and the second light to output a third light having a spectrum different from the first light and the second light, and the first light It may be a backlight unit to which the third light is mixed and output.

According to an embodiment of the display device including the backlight, the bottom cover; A support main fastened to the bottom cover; And a backlight unit disposed between the bottom cover and the support main, the backlight unit comprising: a light source; A light guide member for guiding light output from the light source; A reflection conversion film disposed under the light guide member; And a diffusion conversion film disposed on the light guide member, wherein the reflection conversion film is a film on which a first wavelength conversion layer including a first wavelength conversion material is stacked and positioned on one surface of a reflection film, and the diffusion The conversion film is a film on which a second wavelength conversion layer including a second wavelength conversion material is stacked and positioned on one surface of a diffusion film, wherein the first wavelength conversion material and the second wavelength conversion material are first quantum dot powder and second. Each of at least one of quantum dot powder, and the reflection conversion film converts a first light equal to a spectrum of light output from the light source, so that a second light having a spectrum different from the first light is directed to the light guide member Output, and the diffusion conversion film converts at least a portion of the first light and the second light to output a third light having a spectrum different from the first light and the second light, and the first light It may be a display device in which the third light is mixed and output.

The problem solving means of the present invention is not limited to the above-described solution means, and the solution means not mentioned can be clearly understood by those skilled in the art from the present specification and the accompanying drawings. There will be.

In the backlight unit and the display device including the same, the diffusion conversion film and the reflection conversion film may be disposed on and below the light guide member, so that the light irradiated onto and below the light guide member is the diffusion conversion film and reflection conversion Each can be converted and output by a film.

In the backlight unit and the display device including the same, a diffusion conversion film and a reflection conversion film, each of which has a wavelength conversion layer, are disposed on and under the light guide member, respectively, and the light irradiated onto the light guide member and below. Silver may be converted and output by the wavelength conversion layer, respectively, and the diffusion film and the reflection film may be integrated with the wavelength conversion layer without a barrier film, thereby simplifying the process, improving productivity, and reducing manufacturing costs.

In the backlight unit and the display device including the same, a diffusion conversion film and a reflection conversion film in which a wavelength conversion layer including a plurality of beads, chain molecules, and quantum dots are integrated, are respectively disposed on and under the light guide member. , The wavelength conversion layer, unlike the conventional quantum dot solution by the bead and the chain molecule can be improved phase stability and thermal stability, it can be laminated on the diffusion film and the reflective film without a barrier film, which of the process Effects such as simplification, productivity improvement, manufacturing cost reduction, and light efficiency improvement can be obtained.

In a backlight unit and a display device including the same, a diffusion conversion film and a reflection conversion film in which a wavelength conversion layer in which a complex including a plurality of beads, chain molecules, and quantum dots are separated by an inorganic phosphor are integrated, respectively, are guided by light. It is disposed on the upper and lower members, the wavelength conversion layer can be improved stability of the wavelength conversion layer, unlike the conventional quantum dot solution by the beads, the chain molecule, and the inorganic phosphor, the diffusion film without a barrier film And it can be laminated on a reflective film, which can obtain effects such as simplification of the process, improvement in productivity, reduction in manufacturing cost, improvement in light efficiency, and extension of luminescence life.

The effects of the present invention are not limited to the above-described effects, and the effects not mentioned will be clearly understood by those skilled in the art from the present specification and the accompanying drawings.

1 is a view showing the structure of a backlight unit according to an embodiment.
2 is a view showing the structure of a conventional backlight unit including a quantum dot film.
3 to 5 are views illustrating a spectrum of a backlight unit including the conventional quantum dot film of FIG. 2 and a backlight unit according to an embodiment.
6 to 7 are views illustrating color coordinates of a backlight unit including the conventional quantum dot film of FIG. 2 and a backlight unit according to an embodiment.
8 is a view illustrating a display device including a backlight unit including the conventional quantum dot film of FIG. 2 and a backlight unit according to an embodiment.
9 is a view showing the results of the aging test of the backlight unit including the conventional quantum dot film of FIG.
10 is a view showing an aging test result of a backlight unit according to an embodiment.
11 is a view showing a configuration of a quantum dot powder included in a backlight unit according to an embodiment.
12 and 13 are views illustrating a configuration of a plurality of composites and inorganic phosphors included in the quantum dot powder included in the backlight unit according to an embodiment.
14 is a view showing a configuration of a plurality of components included in a composite according to an embodiment.
15 is a diagram illustrating quantum dots included in a composite according to an embodiment.
16 is a view showing a chain molecule included in the complex according to an embodiment.
17 is a diagram showing the structure of a quantum dot and a chain molecule included in a complex according to an embodiment.
18 is a view showing beads included in a composite according to an embodiment.
19 is a view showing the configuration of a plurality of components included in the composite according to an embodiment.
20 and 21 are views illustrating a distance between a plurality of quantum dots included in a quantum dot powder according to an embodiment.
22 and 23 are views illustrating a distance between a plurality of components included in a quantum dot powder according to an embodiment.
24 is a view showing an SEM image of a quantum dot powder according to an embodiment.
25 is a TEM image of a composite included in a quantum dot powder according to an embodiment, and FIG. 26 is a view showing a TEM image of FIG. 25 enlarged.
27 to 32 are views showing a configuration of a plurality of components included in the quantum dot powder according to an embodiment.
33 is a view showing an effect of a distance between a plurality of quantum dots in a quantum dot powder according to an embodiment on a quantum dot powder.
34 to 39 are views showing acceleration life measurement results according to a ratio of quantum dots and inorganic phosphors included in a quantum dot powder according to an embodiment.
40 is a view showing a peak comparison result according to a ratio of quantum dots and inorganic phosphors included in a quantum dot powder according to an embodiment.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. However, the spirit of the present invention is not limited to the presented embodiments, and a person skilled in the art who understands the spirit of the present invention may add another component within the scope of the same spirit, change, delete, etc. Other embodiments included within the scope of the invention idea can be easily proposed, but this will also be included within the scope of the invention.

In addition, elements having the same functions within the scope of the same idea appearing in the drawings of the respective embodiments will be described using the same reference numerals.

According to an embodiment of the present application, a light source; A light guide member for guiding light output from the light source; A reflection conversion film disposed under the light guide member; And a diffusion conversion film disposed on the light guide member, wherein the reflection conversion film is a film on which a first wavelength conversion layer including a first wavelength conversion material is stacked and positioned on one surface of a reflection film, and the diffusion The conversion film is a film on which a second wavelength conversion layer including a second wavelength conversion material is stacked and positioned on one surface of a diffusion film, wherein the first wavelength conversion material and the second wavelength conversion material are first quantum dot powder and second. Each of at least one of quantum dot powder, and the reflection conversion film converts a first light equal to a spectrum of light output from the light source, so that a second light having a spectrum different from the first light is directed to the light guide member Output, and the diffusion conversion film converts at least a portion of the first light and the second light to output a third light having a spectrum different from the first light and the second light, and the first light A backlight unit in which the third light is mixed and output may be provided.

In addition, the light source is disposed on the side of the light guide member, the first light is provided by a backlight unit, which is irradiated from the light source to the first wavelength conversion layer or the second wavelength conversion layer by the light guide member Can be.

In addition, a region in which peaks appear in the spectrums of the first to third lights correspond to each other, and a backlight unit having a different intensity of the peaks in at least one region among the regions where the peaks appear may be provided.

In addition, the reflection conversion film and the diffusion conversion film may be provided with a backlight unit in which each of the first wavelength conversion layer and the second wavelength conversion layer is disposed adjacent to the light guide member.

In addition, the reflection conversion film and the diffusion conversion film may be provided with a backlight unit, which is disposed spaced apart from the light guide member, respectively.

In addition, an air gap is formed between at least one of the reflection conversion film and the diffusion conversion film and the light guide member, and the first wavelength conversion layer of the reflection conversion film or the diffusion conversion film forming the air gap Alternatively, the second wavelength conversion layer may be provided with a backlight unit exposed to the air gap.

In addition, a backlight unit in which the first wavelength conversion material of the reflection conversion film includes the first quantum dot powder and the second wavelength conversion material of the diffusion conversion film includes the second quantum dot powder can be provided. have.

In addition, the light source emits light in a first wavelength region, and the first quantum dot powder converts and outputs at least a portion of light in the first wavelength region into light in a second wavelength region, and the second quantum dot powder is the At least a portion of the light in the first wavelength region is converted into light in the third wavelength region, and output, and the first wavelength region, the second wavelength region, and the third wavelength region are different, but at least a portion of each region overlaps The backlight unit can be provided.

In addition, at least one of the first quantum dot powder and the second quantum dot powder includes a plurality of quantum dots, chain molecules, and beads, the quantum dots quantum core, a quantum shell surrounding the quantum core, and the surface of the quantum shell It includes a ligand formed in, the chain molecule includes one end and the other end attached to the quantum dot, the bead is located between the other end of the plurality of chain molecules, a backlight unit may be provided.

In addition, the bead may be provided with a backlight unit, which is located spaced apart from the other ends of the plurality of chain molecules.

In addition, a backlight unit in which at least one of the quantum dot, the chain molecule, and the bead is in contact with the diffusion conversion film or the reflection conversion film may be provided.

In addition, the quantum dot includes a first quantum dot and a second quantum dot, the first quantum dot powder includes the first quantum dot, the second quantum dot powder includes the second quantum dot, the first quantum dot and the Each of the second quantum dots may be provided with a backlight unit that converts and outputs light applied from the light source to a different spectrum.

In addition, at least one of the first quantum dot powder and the second quantum dot powder includes a plurality of complexes and inorganic phosphors, the inorganic phosphor is located between the plurality of complexes, the complex is a plurality of the quantum dots, chain molecules, And a bead, wherein the quantum dot includes a quantum core, a quantum shell surrounding the quantum core, and a ligand formed on the surface of the quantum shell, and the chain molecule includes one end and the other end attached to the quantum dot, and The bead may be provided between the plurality of other ends of the chain molecules, and the backlight unit may be spaced apart from the plurality of quantum dots by at least one of the inorganic phosphor, the chain molecule, and the beads.

In addition, a plurality of the composite may be provided with a backlight unit, which is located spaced apart from the inorganic phosphor.

In addition, a backlight unit in which at least one of the plurality of the composites is in contact with the inorganic phosphor may be provided.

In addition, a backlight unit in which at least one of the quantum dot, the chain molecule, the bead, and the inorganic phosphor is in contact with the diffusion conversion film or the reflection conversion film may be provided.

According to an embodiment of the present application, the bottom cover; A support main fastened to the bottom cover; And a backlight unit disposed between the bottom cover and the support main, the backlight unit comprising: a light source; A light guide member for guiding light output from the light source; A reflection conversion film disposed under the light guide member; And a diffusion conversion film disposed on the light guide member, wherein the reflection conversion film is a film on which a first wavelength conversion layer including a first wavelength conversion material is stacked and positioned on one surface of a reflection film, and the diffusion The conversion film is a film on which a second wavelength conversion layer including a second wavelength conversion material is stacked and positioned on one surface of a diffusion film, wherein the first wavelength conversion material and the second wavelength conversion material are first quantum dot powder and second. Each of at least one of quantum dot powder, and the reflection conversion film converts a first light equal to a spectrum of light output from the light source, so that a second light having a spectrum different from the first light is directed to the light guide member Output, and the diffusion conversion film converts at least a portion of the first light and the second light to output a third light having a spectrum different from the first light and the second light, and the first light A display device in which the third light is mixed and output may be provided.

Hereinafter, a backlight unit according to an embodiment of the present application will be described.

1 is a view showing the structure of a backlight unit according to an embodiment.

The backlight unit 1 may be composed of a plurality of components. The backlight unit 1 may include a light source 10, a light guide member 20, a reflection conversion film 30, a diffusion conversion film 40, and a panel 50. The backlight unit 1 is not limited to including only the plurality of components, and may include fewer or more components than the plurality of components.

The backlight unit 1 may output a backlight through a plurality of components. The backlight unit 1 may provide an output backlight converted through a plurality of components to the panel 50. The backlight unit 1 outputs a backlight in which at least a part of light irradiated from the light source 10 is converted through the reflection conversion film 30 or the diffusion conversion film 40, and the converted backlight is the panel 50. The backlight may be defined as light emitted from the light guide member 20 of the backlight unit 1 in an upper direction, a lower direction, and a panel 50 direction. The backlight may be white light. The backlight provided to the panel 50 may select light to be output to the outside of the panel by the panel 50, and accordingly may output light of various colors.

The light source 1 may be positioned adjacent or spaced so that light is irradiated to the light guide member 20. The light source 10 may be positioned adjacent to the surface of the light guide member 20. The light source 10 may be located on the side of the light guide member 20. The light source 1 may be positioned adjacent or spaced apart from the light guide member 20 side. The light source 10 may be located above or below the light guide member 20. The light output from the light source 1 may be transmitted by the light guide member 20. The light output from the light source 1 may be transmitted in a direction different from the output direction by the light guide member 20. The light output from the light source 1 may be transmitted in the upper or lower direction by the light guide member 20.

The light guide member 20 may be located between the reflection conversion film 30 and the diffusion conversion film 40. The light guide member 20 may be positioned adjacent or spaced between the reflection conversion film 30 and the diffusion conversion film 40. The reflection conversion film 30 may be positioned under the light guide member 20, and the diffusion conversion film 40 may be positioned above the light guide member 20. The reflection conversion film 30 may be positioned adjacent or spaced apart from the light guide member 20, and the diffusion conversion film 40 may be adjacent or spaced apart from the light guide member 20. Can be located. Light irradiated from the light source 10 to the light guide member 20 may be transmitted to the reflection conversion film 30 and the diffusion conversion film 40 by the light guide member 20, respectively. At least a portion of the light irradiated from the light source 10 to the light guide member 20 may be transmitted by the light guide member 20 in a lower direction in which the reflection conversion film 30 is located, and the light source 10 ) At least a portion of the light irradiated to the light guide member 20 may be transmitted to the upper direction in which the diffusion conversion film 40 is located by the light guide member 20.

In the backlight unit 1, as shown in FIG. 1, the reflection conversion film 30, the light guide member 20 on which the light source 10 is disposed, the diffusion conversion film 40, and The panels 50 may be stacked and arranged in the order described. At least one of the reflection conversion film 30, the light guide member 20 on which the light source 10 is disposed, the diffusion conversion film 40, and the panel 50 may be spaced apart. The reflection conversion film 30, the light guide member 20 on which the light source 10 is disposed, the diffusion conversion film 40, and the panel 50 may all be spaced apart. The reflection conversion film 30, the light guide member 20 on which the light source 10 is disposed, the diffusion conversion film 40, and the panel 50 are all spaced apart, and the plurality of components An air gap may be formed therebetween.

Hereinafter, a plurality of components included in the backlight unit 1 will be described in detail.

Hereinafter, the light source 10 and the light guide member 20 will be described in detail.

The light source 10 may be disposed on at least one of the upper, lower, and side portions of the light guide member 20. The light source 10 may be disposed adjacent to an area of the side of the light guide member 20. The light source 10 may be disposed adjacent to all regions of the side of the light guide member 20. The light source 10 may be disposed adjacent to the entire area at predetermined intervals on the side of the light guide member 20.

The light source 10 may provide light to each component of the backlight unit 10. The light provided by the light source 10 may be light in a blue wavelength band. The light source 10 may output the light in the direction of the light guide member 20. The light source 10 may include a visible light LED or an infrared LED. The light source 10 may be controlled by the light driving unit so that the light source 10 can emit light.

The light guide member 20 may change a path of light received from the light source 10. The light guide member 20 may be a light guide plate. When the light guide member 20 is a light guide plate, the light source may be disposed on a side of the light guide plate. When the light guide member 20 is a light guide plate, the light source 10 is disposed on the side of the light guide plate, and the light guide plate may be positioned between the reflection conversion film 30 and the diffusion conversion film 40. .

The change of the light path of the light guide plate may be based on scattering, diffusion, or the like. The light guide plate may receive light from the light source 10 and allow predetermined light to be output in various directions. The light guide plate receives light from the light source 10, and the light is scattered in at least one of the direction of the reflection conversion film 30, the direction of the diffusion conversion film 40, and the direction of the panel 50, or Can spread.

The light guide plate may scatter light applied to each region of the light guide plate in various directions. The light guide plate may scatter the light in a first direction in a first region and scatter the light in a second direction in a second region. The light guide plate may emit and convert the applied light into area light based on the scattering. The light guide plate may receive the light and output it in a specific direction. The specific direction may be at least one of the direction of the reflection conversion film 30, the direction of the diffusion conversion film 40, and the direction of the panel 50. The light guide plate may scatter or reflect the light in at least one of the direction of the reflection conversion film 30, the direction of the diffusion conversion film 40, and the direction of the panel 50 in a specific area to be output.

The light guide plate may be made of a material capable of changing the light path. The material may include PMMA (Polymethyl metacrylate)-based resin, and olefin-based resin (COC). The light guide plate may be formed with a predetermined optical pattern. The optical pattern may be defined as a pattern formed by the light guide plate by a predetermined processing method to improve the brightness of the backlight unit 1.

Hereinafter, the reflection conversion film 30 and the diffusion conversion film 40 will be described in detail.

The reflection conversion film 30 may include a first wavelength conversion layer 301 and a reflection film 305. The diffusion conversion film 40 may include a second wavelength conversion layer 401 and a diffusion film 405.

The reflection conversion film 30 may be positioned such that the first wavelength conversion layer 301 is adjacent or spaced apart from the reflection film 305. The reflective conversion film 30 may be located on the reflective film 305, the first wavelength conversion layer 301 is adjacent or spaced apart. The reflection conversion film 30 may be positioned on the reflective film 305 by stacking the first wavelength conversion layer 301. The diffusion conversion film 40 may be positioned such that the second wavelength conversion layer 401 is adjacent or spaced apart from the diffusion film 405. The second wavelength conversion layer 401 may be positioned adjacent to the diffusion conversion film 40 under the diffusion film 405. The diffusion conversion film 40 may be positioned by stacking the second wavelength conversion layer 401 under the diffusion film 405.

The first wavelength conversion layer 301 and the second wavelength conversion layer 401 may be stacked on the reflective film 305 and the diffusion film 405 with a predetermined thickness, respectively. The first wavelength conversion layer 301 and the second wavelength conversion layer 401 may be uniformly stacked on the reflective film 305 and the diffusion film 405 with a predetermined thickness, respectively. In addition, an air gap may be formed between at least one of the reflection conversion film 30 and the diffusion conversion film 40 and the light guide plate, and the first wavelength conversion layer 301 and the second wavelength conversion layer may be formed. At least one of 401 may be exposed to the air gap.

The first wavelength conversion layer 301 and the second wavelength conversion layer 401 may include a first wavelength conversion material and a second wavelength conversion material, respectively. The first wavelength conversion layer 301 and the second wavelength conversion layer 401 each include a first wavelength conversion material and a second wavelength conversion material, respectively, the first wavelength conversion material and the second wavelength conversion material In addition to the base material may be further included. The base material may be mixed with the first wavelength converting material or the second wavelength converting material, so that the first wavelength converting layer 301 and the second wavelength converting layer 401 are the reflective film 30 and It may be laminated on the diffusion film 40. The base material may be resin. The base material may be a resin corresponding to at least one of acrylic, silicone, urethane, thermoset and UV series.

The first wavelength conversion layer 301 and the second wavelength conversion layer 401 may be respectively laminated on the reflective film 305 and the diffusion film 405 through an adhesive material. The adhesive material may be transparent adhesive materials, for example, OCA or PDMA material.

The first wavelength conversion layer 301 and the second wavelength conversion layer 401 may be stacked on the reflective film 305 and the diffusion film 405, respectively, to be integrated. As the first wavelength conversion layer 301 and the second wavelength conversion layer 401 are stacked and integrated on the reflective film 305 and the diffusion film 405, respectively, the thickness of the backlight unit 1 is increased. Can be reduced. In addition, accordingly, it is possible to bring about an effect of simplifying the process, improving productivity, and reducing manufacturing cost.

Further, the first wavelength conversion layer 301 may include the first wavelength conversion material, and the second wavelength conversion layer 401 may include the second wavelength conversion material. The first wavelength converting material and the second wavelength converting material may include at least one of a first quantum dot powder and a second quantum dot powder.

Light may have a predetermined spectrum, which may mean that light may have intensity for each wavelength region. When the light source emits the first light in the first wavelength region, the first quantum dot powder may convert and output at least a portion of the light in the first wavelength region into the second light in the second wavelength region. In addition, the second quantum dot powder may convert and output at least a portion of light in the first wavelength region of the first light into third light in the third region. The first wavelength region, the second wavelength region, and the third wavelength region may be different. The first wavelength region, the second wavelength region, and the third wavelength region are different, but at least a portion of each region may overlap. In the first wavelength region, the second wavelength region, and the third wavelength region, numerical values of the wavelength region may be increased in the order described. The first wavelength region may be a blue band (400 mm to 500 mm), the second wavelength region may be a green band (500 mm to 600 mm), and the third wavelength region may be a red band (600 mm to 700 mm). In addition, when the first quantum dot powder converts and outputs at least a portion of light in the first wavelength region to third light in the third wavelength region, the second quantum dot powder extracts at least a portion of light in the first wavelength region. The second light in the second wavelength region may be converted and output.

The light output from the light source, the light converted by the first quantum dot powder, and the light converted by the second quantum dot powder may each have peaks corresponding to the first to third wavelength regions. . The light output from the light source, the light converted by the first quantum dot powder, and the light converted by the second quantum dot powder may each have peaks corresponding to the first wavelength region to the third wavelength region. , Intensities of the peaks in each region may be different from each other.

When the first wavelength-converting material includes the first quantum dot powder, the second wavelength-converting material may include the second quantum dot powder, and the first wavelength-converting material includes the second quantum dot powder The second wavelength conversion material may include the first quantum dot powder. In the first wavelength conversion material and the second wavelength conversion material, the first quantum dot powder and the second quantum dot powder may be mixed in a predetermined ratio, respectively. In the first wavelength conversion material and the second wavelength conversion material, the first quantum dot powder and the second quantum dot powder may be mixed at different ratios, respectively. A more detailed description of the first quantum dot powder and the second quantum dot powder will be described later.

The reflective film 305 may reflect light applied from the light source 10. The reflective film 305 may reflect light converted by the first wavelength conversion layer 301 on at least a part of light applied from the light guide member 20. The reflective film 305 reflects at least a portion of the light applied from the light guide member 20, and at least a portion of the light applied from the light guide member 20 is converted by the first wavelength conversion layer 301. The reflected light can be reflected. In the reflective film 305, the light incident on the reflective film 305 is in the first wavelength conversion layer 301 direction, the light guide member direction 20, the diffusion conversion film 40 direction, and the panel 50 direction. It can be reflected to output in the upper direction of the back. In the reflection conversion film 30, at least a portion of the light reflected by the reflection film 305 is converted by a wavelength by the first wavelength conversion layer 301, in the direction of the first wavelength conversion layer 301, the light guide member It may be reflected so as to be output in the upper direction such as the direction 20, the direction of the diffusion conversion film 40, and the direction of the panel 50.

The reflective film 305 may be a film including a material capable of reflecting light applied from the light source 10. When the reflective film 305 is implemented as a diffuse reflective film, the reflective film 305 may include a diffuse reflective material. The diffusion reflective material may include barium sulfate (Ba ₂ SO ₄ ). When the reflective film 305 is implemented as a specular reflective film, the reflective film 305 may include a specular reflective material. The specular reflective material may include aluminum (Al)-based or silver (Ag)-based materials. When the reflective film 305 is implemented in the form of a combination thereof, the reflective film 305 may include at least one of the above-described materials. If the material is capable of reflecting the light applied from the light source 10, the reflective film 305 may include the material.

The diffusion film 405 may diffuse light applied from the light source 10, the light guide member 20, and the reflective film 30. The diffusion film 405 converts and diffuses at least a portion of light applied to the light source 10, the light guide member 20, and the reflective film 30 by the second wavelength conversion layer 401. Can. The diffusion film 405 ensures at least a portion of the light applied to the light source 10, the light guide member 20, and the reflective film 30, while the light source 10, the light guide member 20, And at least a portion of the light applied to the reflective film 30 may be converted and diffused by the second wavelength conversion layer 401.

The diffusion film 405 may be a film including a material capable of diffusing light applied from the light source 10, the light guide member 20, and the reflective film 30. If the light source 10, the light guide member 20 and a material capable of diffusing the light applied from the reflective film 30, the diffusion film 405 may include the material.

Hereinafter, the panel 50 will be described in detail.

The panel 50 may change the optical properties of the backlight. The panel 50 may change the optical properties of the backlight based on the polarization structure. The panel 50 may include liquid crystal. The liquid crystal of the panel 50 may have a predetermined polarization structure. The polarization structure of the liquid crystal may be formed by applying electrical energy to the liquid crystal. By applying a liquid crystal control signal to the panel 50, a plurality of liquid crystals included in the panel 50 may be arranged in a predetermined direction. The polarization structure may be defined by the arranged liquid crystals.

The backlight unit 1 may include the components shown in FIG. 1, but the component shown in FIG. 1 is not an essential component, and the backlight unit 1 has more or less components than the components shown in FIG. 1. This can be implemented.

Hereinafter, the backlight unit 1 will be described in detail through comparison with the conventional backlight unit 2.

2 is a view showing a structure of a backlight unit 2 including a conventional quantum dot film.

The backlight unit 2 including a conventional quantum dot film includes a light source 15, a light guide member 25, a reflective film 35, a diffusion film 45, a panel 55, and a quantum dot film 65 Can. The quantum dot film 65 may include a quantum dot layer 651, a first barrier film 653, and a second barrier film 655. In the quantum dot film 65, the quantum dot layer 651 is positioned between the first barrier film 653 and the second barrier film 655. That is, in the conventional quantum dot film, the quantum dot layer 651 is wrapped with a double barrier film. This is a barrier film disposed above and below the quantum dot layer 651 to maintain thermal and phase stability of the quantum dot layer 651. The quantum dot layer 651 is a form in which red quantum dots and green quantum dots are mixed.

Hereinafter, a spectrum output from the conventional backlight unit 2 and the backlight unit 1 will be compared.

3 to 5 are views illustrating a spectrum of a backlight unit including the conventional quantum dot film of FIG. 2 and a backlight unit according to an embodiment. 3 shows a spectrum comparison between the conventional backlight unit 2 and the backlight unit 1. 4 shows a spectrum comparison according to the configuration of the first wavelength conversion layer 301 and the second wavelength conversion layer 401 of the backlight unit 1, and FIG. 5 shows a conventional backlight unit 2 Spectrum comparison according to the difference in thickness of the quantum dot film 65 is shown,

3 to 5, the BLED Bare relates to a spectrum output from the light source 10, and in the first type of Double A, the first wavelength conversion layer 301 includes red quantum dots, and the second wavelength conversion layer 401 denotes a backlight unit 1 including green quantum dots. Further, in the second type Double B, the first wavelength conversion layer 301 includes a green quantum dot, and the second wavelength conversion layer 401 means a backlight unit 1 including a red quantum dot. In addition, the third type Double C means a backlight unit 1 in which the first wavelength conversion layer 301 and the second wavelength conversion layer 401 are respectively mixed with red quantum dots and green quantum dots at a predetermined ratio. do. In addition, the fourth type of Normal A is a case where the thickness of the quantum dot film 65 is 100um, and the fifth type of Normal B is a conventional backlight unit where the thickness of the quantum dot film 65 is 200um. .

3, the spectrum of the light output from the light source 10 has a peak in the region of 400nm to 500nm, it can be seen that the intensity of the peak is very large. It can be seen that the five types of backlight units used in the experiment commonly convert the light of the light source 10 having a peak in the region of 400 nm to 500 nm into 500 nm to 600 nm region and 600 nm to 700 nm region, respectively. How much the five types of backlight units convert light from the light source 10 may affect the light efficiency of the backlight unit.

Spectral results of the five types of backlight units will be described in more detail with reference to FIGS. 3 and 4.

First, a region of 400 nm to 500 nm is defined as a first wavelength region, a region of 500 nm to 600 nm is defined as a second wavelength region, and a region of 600 nm to 700 nm is defined as a third wavelength region, and a peak appearing in the first wavelength region is a first peak, A peak appearing in the second wavelength region is defined as a second peak, and a peak appearing in the third wavelength region is defined as a third peak.

As illustrated in FIG. 4, in the case of the backlight units of the first type to the third type, the intensity of the first peak is the greatest, but the intensity of the first peak is relatively higher than the first peak of the light source 1. It has been greatly reduced, and the second peak is a peak having the intensity of the second size, and the third peak has an intensity of the third size. In addition, in the case of the first type, it can be confirmed that the first and second peaks are larger than those of the second type and the third type, and that the size of the third peak is almost similar to the third type. Can be confirmed. In the case of the second type, it can be seen that the first to third peaks have lower intensities than the first type and the third type. In the case of the third type, it can be seen that the first peak and the second peak have lower intensities than the first type, but are larger than the second type, and the third peak is larger than the first type, but the difference is very small. In consideration of this, through the comparison of the intensity of the first peak to the third peak, the first type has superior light conversion to the second wavelength region and the third wavelength region compared to the second type and the third type. Through this, it can be seen that the first type has the best light efficiency.

As shown in FIG. 5, in the case of the backlight unit of the fourth type and the fifth type, it can be seen that the intensity of the first peak is very large compared to the second peak and the third peak. This may mean that light in the first wavelength region output by the light source 10 is not sufficiently converted. In the case of the fifth type, the intensity of the first peak is lower than that of the fourth type, but it can be seen that the intensity of the second and third peaks is almost similar to the fourth type.

Accordingly, when considering FIG. 3 shown in combination with FIGS. 4 and 5, it can be confirmed that the first type is the type that converts light in the first wavelength region of the light source 10 most efficiently. In addition, the first type to the third type of the backlight unit 1 are higher in the second wavelength region and the third wavelength region than the fourth and fifth types of the conventional backlight unit 2. It can be confirmed that the peak of, it can be confirmed that the backlight unit 1 has a higher light efficiency than the conventional backlight unit (2).

Table 1 is a result of comparing the quantum yield (QY) by spectral integration for each spectrum shown in Figures 3 to 5.

No Type 450nm
Source Spectrum Integral A B B/A Blue Green Red Blue Bare-Blue Green +Red QY One Double A 13.6 4.0 2.6 2.1 9.6 4.7 49% 2 Double B 2.9 1.8 1.6 10.7 3.4 31% 3 Double C 3.4 2.1 2.2 10.2 4.3 42% 4 Normal A 5.5 1.4 1.0 8.2 2.4 29% 5 Normal B 5.5 1.3 0.9 8.1 2.2 27%

The result is that light of the same intensity is irradiated with the same light source 10 to the first type to the fifth type. In addition, QY is the green of the light emitted from the light source 10 or the sum of the intensity of light corresponding to green or red among the light converted by the quantum dots, based on the intensity of light that is the blue bare of the light source 10. It can be defined as dividing by the intensity of blue light that is not converted to red. At this time, as shown in Table 1, it can be seen that the first type has the largest QY value at 49%. This means how much light can be efficiently converted to other wavelength bands without loss of light compared to the light irradiated from the light source 10 in consideration of the intensity of light whose wavelength is converted due to quantum dots. Therefore, in the case of the first type, it means that 49% of the remaining light except for the blue light that is not converted among the blue light irradiated from the light source 10 is converted to another wavelength band. Even in the case of the third type, it can be seen that the QY value is 40% or more. In the case of the second type, it has a QY value of 31%, but it can be seen that it has a larger value than the fourth and fifth types of the conventional backlight unit 2.

When the QY value is lower than 30%, the intensity of blue light is relatively increased, which may result in quantum dot damage due to photon damage of blue light. Therefore, the structure of the conventional backlight unit 2 may result in a decrease in life due to quantum dot damage. When the QY value is higher than 40%, the quantum dot damage is reduced compared to the conventional backlight unit 2, so that the life of the quantum dots included in the product can be extended.

The result may be due to a difference in structure between the backlight unit 1 and the conventional backlight unit 2. In the case of the conventional backlight unit 2, barrier films are disposed on upper and lower portions of the quantum dot film, and light output from the light source 15 may cause light loss due to the optical waveguide of the barrier film. . In addition, in the conventional backlight unit 2, light transmission loss may occur due to a decrease in transmittance due to the barrier film. Therefore, in the case of the conventional backlight unit 2, a result in which the light emission efficiency is significantly reduced can be derived. On the other hand, the backlight unit 1, without a separate barrier film, the first wavelength conversion layer 301 or the second wavelength conversion layer 401, the reflection conversion film 30 and the diffusion conversion film (integrated respectively) In the point of using 40), light loss or light transmission loss due to the barrier film can be reduced, thereby improving light efficiency.

In addition, in the case of the conventional backlight unit 2, blue light is irradiated to one quantum dot film 60 to convert the wavelength, whereas in the case of the backlight unit 1, blue light is emitted in the upper and lower directions of the light guide member. As it is dispersed and wavelengths are converted by the reflection conversion film 30 and the diffusion conversion film 40, photon damage caused by the blue light may be minimized.

In addition, when the existing red quantum dots and green quantum dots are mixed, the emission intensity reduction (Quenchinng) generated between the red quantum dots and the green quantum dots may occur. Therefore, compared to the case of mixing the red quantum dots and the green quantum dots in the same quantum dot film or wavelength conversion layer, it is possible to increase the light emission intensity by separately including the red quantum dots or green quantum dots in each of the plurality of quantum dot film or wavelength conversion layer. .

Accordingly, when considering the effects of the structure and the quantum dot configuration, the light efficiency of the first type backlight unit 1 may be highest. However, this specification is not limited to the above, and the result may be different depending on the components and quantum dots constituting the backlight unit 1.

6 to 7 are views illustrating color coordinates of a backlight unit including the conventional quantum dot film of FIG. 2 and a backlight unit according to an embodiment. 8 is a view illustrating a display device including a backlight unit including the conventional quantum dot film of FIG. 2 and a backlight unit according to an embodiment.

6 shows color coordinates of the first to third types of backlight units 1, and FIG. 7 shows color coordinates of the conventional backlight units 2 of the fourth and fifth types. The color coordinates may be defined as coordinates for indicating the color reproduction rate, and various colors may be expressed as the color coordinates are closer to white light. In FIG. 8, (a) is a result showing light output from the display unit of the backlight unit 1, and (b) is a result showing light output from the display unit of the conventional backlight unit 2.

Table 2 shows the color coordinate results of the first to fifth types of backlight units.

No Type Luminance (cd/m ² ) CIEx CIEy One Double A 2,223 0.2526 0.2471 2 Double B 1,874 0.2549 0.2397 3 Double C 1,551 0.2666 0.2421 4 Normal A 1,244 0.1971 0.1363 5 Normal B 1,207 0.2129 0.1603

Referring to Tables 2, 6, and 8(a), it can be seen that the color coordinates of the first type to the third type of backlight unit 1 are near the white light. This means that the backlight units 1 of the first type to the third type can output light almost similar to white light. In addition, the first type to the third type of backlight unit 1 may control the white light output from the panel 50 to output light of various colors. Accordingly, the backlight units 1 of the first to third types may have a high color gamut, and thus may be used for a display having a high color gamut.

Referring to Tables 2, 7, and 8(b), it can be seen that the color coordinates of the conventional backlight unit 2 of the fourth and fifth types are relatively close to blue light. This means that the backlight units 1 of the fourth type and the fifth type can output light substantially similar to blue light rather than white light. In addition, even if the backlight unit 1 of the fourth type and the fifth type outputs red or green light other than blue light, it is difficult to provide various colors of light in the panel 50 because its intensity is very weak. will be.

Therefore, the first to third types of backlight units 1 can reproduce more various light than the fourth and fifth types of conventional backlight units 2, and have high light efficiency and color reproducibility. The first to third types of backlight units 1 may be included and used in various display devices.

Hereinafter, a result of comparing the aging test of the conventional backlight unit 2 and the backlight unit 1 will be described in detail.

9 is a view showing the results of the aging test of the backlight unit including the conventional quantum dot film of FIG. 10 is a view showing an aging test result of a backlight unit according to an embodiment.

Referring to FIG. 9, it can be confirmed that in the case of the conventional backlight unit 2, the light efficiency of the green quantum dot and the red quantum dot is relatively largely decreased over time, respectively. However, referring to FIG. 10, it can be seen that, in the case of the backlight unit 1, the light efficiency of the green quantum dot and the red quantum dot is maintained unchanged over time, respectively. This, as described above, the backlight unit 1, unlike the conventional backlight unit 2, the blue light is dispersed in the upper and lower directions of the light guide member by the reflection conversion film 30 and the diffusion conversion film 40 This is because the photon damage caused by the blue light can be minimized as the wavelength is converted. In addition, unlike the conventional backlight unit 2, the backlight unit 1 may reduce the emission intensity (Quenchinng) generated between the red quantum dot and the green quantum dot when the red quantum dot and the green quantum dot are not mixed.

Accordingly, the first to third type backlight units 1 can output light having higher stability and light efficiency than the conventional backlight units 2 of the fourth and fifth types, and have high light efficiency. And the first to third type backlight units 1 having stability may be included in various display devices and used.

In consideration of the technical features and effects of the backlight unit 1 described above, various display devices including the same can be implemented. The display device may include the backlight unit 1, a bottom cover, an optical sheet, a support main, a display panel 50, a printed circuit board, an FPC, and a top cover. However, these components are not essential components of the display device, and a display device having more or less components may be implemented.

Hereinafter, a quantum dot powder constituting at least one of the first wavelength conversion layer 301 and the second wavelength conversion layer 401 of the backlight unit 1 will be described in detail. The quantum dot powder may be defined as including the first quantum dot powder and the second quantum dot powder.

11 is a view showing a configuration of a quantum dot powder included in a backlight unit according to an embodiment.

The quantum dot powder 1001 may be composed of a plurality of particles. The quantum dot powder 1001 may include a plurality of complexes 1010 and inorganic phosphors 1020. The quantum dot powder 1001 may include a plurality of adjacent complexes 1010 and inorganic phosphors 1020. The quantum dot powder 1001 may include a plurality of complexes spaced apart by the inorganic phosphor 1020. However, the components shown in FIG. 1 are not essential, and a quantum dot powder 1001 having more or fewer components may be implemented.

The quantum dot powder 1001 converts the wavelength of the irradiated light, so that light in a specific wavelength band can be output. The quantum dot powder 1001 converts the wavelength of the irradiated light by the plurality of the composite 1010 and the inorganic phosphor 1020, so that light in a specific wavelength band can be output. In addition, the quantum dot powder 1001 may be spaced apart from the plurality of composites 1010 by the inorganic phosphor 1020, thereby improving dispersibility of the plurality of composites 1010. The quantum dot powder 1001 is a plurality of the complex 1010 is spaced apart by the inorganic phosphor 1020, and improves the dispersibility of the plurality of the complex 1010 thermal stability of the quantum dot powder 1001 This can be improved. The quantum dot powder 1001 is spaced apart by a plurality of the complex 1010 by the inorganic phosphor 1020, thereby improving the dispersibility of the plurality of the complex 1010, the quantum efficiency of the quantum dot powder 1001 And luminescence properties can be maintained.

Hereinafter, a configuration of a plurality of composites 1010 and inorganic phosphors 1020 included in the quantum dot powder 1001 will be described.

12 and 13 are diagrams illustrating a configuration of a plurality of composites 1010 and inorganic phosphors 1020 included in a backlight unit according to an embodiment. The structures of the plurality of composites 1010 and inorganic phosphors 1020 will be described with reference to FIGS. 12 to 13.

As illustrated in FIG. 12, a plurality of the complexes 1010 and the inorganic phosphors 1020 included in the quantum dot powder 1001 may be spaced apart from each other. The plurality of composites 1010 included in the quantum dot powder 1001 may be positioned spaced apart from the inorganic phosphor 1020. The plurality of complexes 1 included in the quantum dot powder 1001 may be positioned adjacent to and spaced apart from the inorganic phosphor 1020. The plurality of composites 1 included in the quantum dot powder 1001 may be positioned at a predetermined distance from the inorganic phosphor 1020. Therefore, a plurality of the complexes 1010 in the quantum dot powder 1001 may be spaced apart by the inorganic phosphor 1020. In the quantum dot powder 10, a plurality of the composites 1010 may have a predetermined physical gap by the inorganic phosphor 1020. The physical spacing between the composites 1010 may contribute to maintaining quantum efficiency and luminescence properties of the quantum dot powder 10.

As shown in FIG. 13, a plurality of the complexes 1010 and the inorganic phosphors 1020 included in the quantum dot powder 1001 may be positioned in contact with each other. At least one of the plurality of composites 1010 included in the quantum dot powder 1001 may be located in contact with the inorganic phosphor 1020. The plurality of composites 1010 included in the quantum dot powder 1001 may be located in contact with the inorganic phosphor 1020. Therefore, a plurality of the complexes 1010 in the quantum dot powder 1001 may be spaced apart by the inorganic phosphor 1020. In the quantum dot powder 1001, a plurality of the composites 1010 may have a predetermined physical gap by the inorganic phosphor 1020. The physical spacing between the composites 1010 may contribute to maintaining quantum efficiency and luminescence properties of the quantum dot powder 10.

The inorganic phosphor 1020 will be described in detail with reference to FIGS. 11 to 13.

The inorganic phosphor 1020 may be an inorganic material having fluorescence, and there is no particular limitation. In addition, the inorganic phosphor 1020 may be a material capable of separating a plurality of the composites 1010.

The inorganic phosphor 1020 may have a predetermined size. The inorganic phosphor 1020 may have a size capable of separating a plurality of the composites 1010. The inorganic phosphor 1020 may have a size of 1um to 20um. The diameter of the inorganic phosphor 1020 may have a size of 1um to 20um.

-SiAlON:Eu²⁺, (Ca,Sr,Ba)₂P₂O₇:Eu²⁺,Mn²⁺, (Ca,Sr,Ba)₅(PO₄)₃Cl:Eu²⁺, Lu₂SiO₅:Ce³⁺, (Ca,Sr,Ba)₃SiO₅:Eu²⁺, (Ca,Sr,Ba)₂SiO₄:Eu²⁺, Zn₂SiO₄:Mn²⁺, BaAl₂O₁₉:Mn²⁺, BaMgAl₁₄O₂₃:Mn²⁺, SrAl₁₂O₁₉:Mn²⁺, CaAl₁₂O₁₉ Mn²⁺, YBO₃:Tb³⁺, LuBO₃:Tb³⁺, Y₂O₃:Eu³⁺, Y₂SiO₅:Eu³⁺, Y₃Al₅O₁₂:Eu³⁺, YBO₃: Eu ³⁺, Y_0.65Gd_0.35BO₃:Eu³⁺, GdBO₃:Eu³⁺, YVO₄:Eu³⁺, 및 (Y,Gd)₃(Al,Ga)₅ O₁₂:Ce³⁺ 등의 형광체 중 적어도 어느 하나일 수 있다. The inorganic phosphor 1020 is (Y,Tb) ₃ Al ₅ O ₁₂ :Ce ³⁺ , (Sr,Ba,Ca) ₂ Si ₅ N ₈ :Eu ²⁺ , CaAlSiN ₃ :Eu ²⁺ , BaMgAl ₁₀ O ₁₇ :Eu ²⁺ , BaMgAl ₁₀ O ₁₇ :Eu ²⁺ ,Mn ²⁺ , Ca-α-SiAlON:Eu ²⁺ ,

-SiAlON:Eu ²⁺ , (Ca,Sr,Ba) ₂ P ₂ O ₇ :Eu ²⁺ ,Mn ²⁺ , (Ca,Sr,Ba) ₅ (PO ₄ ) ₃ Cl:Eu ²⁺ , Lu ₂ SiO ₅ : Ce ³⁺ , (Ca,Sr,Ba) ₃ SiO ₅ :Eu ²⁺ , (Ca,Sr,Ba) ₂ SiO ₄ :Eu ²⁺ , Zn ₂ SiO ₄ :Mn ²⁺ , BaAl ₂ O ₁₉ : Mn ²⁺ , BaMgAl ₁₄ O ₂₃ :Mn ²⁺ , SrAl ₁₂ O ₁₉ :Mn ²⁺ , CaAl ₁₂ O ₁₉ Mn ²⁺ , YBO ₃ :Tb ³⁺ , LuBO ₃ :Tb ³⁺ , Y ₂ O ₃ :Eu ³⁺ , Y ₂ SiO ₅ :Eu ³⁺ , Y ₃ Al ₅ O ₁₂ :Eu ³⁺ , YBO ₃ : Eu ³⁺ , Y _0.65 Gd _0.35 BO ₃ :Eu ³⁺ , GdBO ₃ :Eu ³⁺ , YVO ₄ :Eu ³⁺ , and (Y,Gd) ₃ (Al,Ga) ₅ O ₁₂ :Ce ³⁺ .

The inorganic phosphor 1020 may be positioned between a plurality of the complexes 1010 included in the quantum dot powder 1001. The inorganic phosphor 1020 may separate a plurality of the complexes 1010 included in the quantum dot powder 1001. The inorganic phosphor 1020 may contact or be spaced apart from a plurality of the complexes 1010 included in the quantum dot powder 1001 to separate the plurality of the complexes 1010. The inorganic phosphor 1020 may have a size of about 30 to 50 times that of the complex 1010, so that the plurality of complexes 1010 can be effectively separated.

In addition, the inorganic phosphor 1020 is a wavelength conversion material, and may emit light by converting at least a part of the wavelength of the irradiated light. The inorganic phosphor 1020 can improve the dispersibility of the complexes 1010 by separating the plurality of the complexes 1010 included in the quantum dot powder 1001, and at the same time, the inorganic phosphors 1020. May emit light by converting a wavelength of at least a part of the irradiated light. The inorganic phosphor 1020 has a large half-value width compared to a quantum dot, and may serve as an auxiliary in wavelength conversion of the composite 1010.

Hereinafter, a configuration of a plurality of the composites 1010 included in the quantum dot powder 1001 will be described.

14 is a view showing a configuration of a plurality of elements constituting the composite 1010 according to an embodiment. Referring to FIG. 14, a relationship between a plurality of elements constituting the composite 1010 will be described.

The composite 1010 may be composed of a plurality of particles. The complex 1010 may include quantum dots 2100, chain molecules 2200, and beads 2300. However, the components shown in FIG. 14 are not essential, and a composite 1010 having more or fewer components may be implemented.

The quantum dot 2100 may be a particle implemented to emit light in a specific wavelength band. The quantum dot 2100 may receive a predetermined energy and emit light in the specific wavelength band.

The chain molecule 2200 may be attached to the quantum dot 2100 so that the distance between the adjacent quantum dots 2100 is spaced apart.

The beads 2300 may be positioned spaced apart between the plurality of chain molecules 2200. The beads 2300 may be positioned spaced apart between the other ends of the plurality of chain molecules 2200. The beads 2300 may be positioned in contact with a plurality of the chain molecules 2200. The beads 2300 may be located in contact with the other ends of the plurality of chain molecules 2200.

Hereinafter, each configuration of the composite 1010 will be described in detail.

15 is a diagram illustrating quantum dots included in a composite according to an embodiment. First, the quantum dot 2100 will be described with reference to FIGS. 14 to 15.

The quantum dot 2100 is a nano-sized semiconductor material, and is a material having a quantum confinement effect. Based on the quantum limiting effect, the quantum dot 2100 may emit light. The quantum dot 2100 absorbs light from an excitation source to reach an energy excitation state, and emits energy corresponding to an energy band gap of the quantum dot 2100. The quantum dot 2100 receives a predetermined light and has active electrons (Excitation eletron), and the active electrons are stabilized to emit energy.

The quantum dot 2100 may have various energy band gaps depending on the size of the quantum dot 2100 or the material composition of the quantum dot 2100. The quantum dot 2100 may emit light in a specific wavelength band corresponding to the energy band gap. The quantum dot 2100 may change the size or material composition of the quantum dot 2100 to emit light in the specific wavelength band.

The quantum dot 2100 may be implemented with a predetermined compound. The predetermined compound may be at least one of a II-VI compound, a III-V compound, and a IV-VI compound.

The II-VI compound is a CdSe, CdTe, ZnS, ZnTe, ZnO, HgS, HgSe, HgTe, or other binary compound or CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTn, CgTe Three-element compounds such as CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, or HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgZe, HdZgSe, H,

The group III-V compounds include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, etc., or GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, Three element compounds such as AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, or GaAlNAs, GaAlNsb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InPA It may be selected from the group consisting of a quaternary compound such as.

The group IV-VI compound is a binary element compound such as SnS, SnSe, SnTe, PbS, PbSe, PbTe, or a three-membered compound such as SnPbS, SnPbSe, SbPbTe, SnPbS, SnPbSe, SbPbTe, SnPbS, SnPbSe, SbPbTe , SnPbSTe, and the like.

The group IV compound may be selected from the group consisting of single element compounds such as Si and Ge or binary elements such as SiC and SiGe.

The quantum dot 2100 may have a core-shell structure. The core-shell structured quantum dot 2100 may include a quantum core (Quantum-core, 2110) and a quantum shell (Quantum-shell, 130).

The quantum core 2110 may emit light based on a quantum limiting effect. The quantum shell 2130 may cover the quantum core 2110. The quantum shell 2130 may protect the quantum core 2110. The quantum shell 2130 may prevent the energy band of the quantum core 2110 from being changed. Meanwhile, the quantum core 2110 and the quantum shell 2130 may be implemented with the aforementioned compounds.

The components shown in FIG. 15 are not essential, and a quantum dot 2100 having more or fewer components may be implemented. For example, a predetermined coating layer may be formed on the quantum shell 2130 of the quantum dot 2100. The coating layer may be a layer implemented to improve durability of the quantum dot 2100.

The quantum dot 2100 may further include a ligand 2150. The ligand 2150 may be formed on the surface of the quantum dot 2100. The ligand 2150 may be attached to the surface of the quantum shell 2130. The ligand 2150 may be a compound that coordinates by providing a covalent electron pair to the quantum dot 2100.

The ligand 2150 may include an organic ligand, an inorganic ligand, or a combination ligand combining the aforementioned ligands.

The organic ligand may be an alkyl chain molecule. The alkyl chain molecule may include at least one of oleic acid (OA), 1,2-ethylenedithiol (EDT), 1,4-butanedithiol (BDT), or 3-mecaptopropionic acid (MPA).

The inorganic ligand may include at least one of ether-based compounds, unsaturated hydrocarbons, and organic acids. The solvent used as the inorganic ligand may include at least one of ether-based compounds, unsaturated hydrocarbons, or organic acids. The ether-based compound may include at least one of tri-n-octylphosphine oxide (TOP), alkyl phosphine, octylether, and benzyl ether (Benzylether). The unsaturated hydrocarbons may include at least any one of Octane and Octadecane. The organic acid may include at least one of oleic acid, stearic acid, myristic acid, and hexadecanoic acid.

Thermal stability may be improved by the ligand 2150 included in the quantum dot 2100 described above. In addition, the ligand 2150 prevents a plurality of the quantum dots 2100 from agglomerating with each other, thereby preventing a decrease in the light efficiency of the quantum dot powder.

Hereinafter, the chain molecule 2200 will be described.

16 is a view showing a chain molecule (2200) contained in a complex according to an embodiment. The chain molecule 2200 will be described in detail with reference to FIGS. 11 to 16.

The chain molecule 2200 may include a head 2210 and a tail 2230. The head 2210 and the tail 2230 may have predetermined chemical properties. The chemical property may include a hydrophilic property (Hydrophilic property) and a hydrophobic property (Hydrophobic property). The hydrophilicity can be defined by a certain hydrophilic group. For example, the hydrophilic group may be at least one of a hydroxyl group (-OH), a carboxyl group (-COOH), and an amino group (-NH ₂ , -NHR, -NR ₂ , and R is an alkyl group). The hydrophobicity may be defined by a predetermined hydrophobic group. For example, the hydrophobic group may be a hydrocarbon group (C _n H _m ).

The head 2210 and the tail 2230 may have different chemical properties from each other. For example, when the head 2210 is hydrophilic, the tail 2230 may be hydrophobic, and when the head 2210 is hydrophobic, the tail 2230 may be hydrophilic. Alternatively, the head 2210 and the tail 2230 may have the same chemical properties.

The tail 2230 may have a predetermined chemical shape. For example, when the tail is a hydrocarbon group, the chemical shape of the tail may be a chain shape. The tail 2230 may define a physical structure of the chain molecule 2200. By the tail 2230, the chain molecule 2200 may have a predetermined physical length. For example, when the tail 2230 is a hydrocarbon group, the tail 2230 may have a predetermined length based on the number of carbons (C) included. The length of the tail 2230 may be proportional to the number of carbons (C) included.

The chain molecule 2200 may be a stearic compound. The chain molecule 2200 may be, for example, a type of stearic acid. The stearic acid is magnesium stearate, calcium stearate, zinc stearate, lithium stearate, sodium stearate, or aluminum stearate stearate).

When the chain molecule 2200 is zinc stearate, the chain molecule 2200 may include a head 2210 composed of a carboxyl group (hydrophilic group) and a tail 2230 composed of a hydrocarbon group (hydrophobic group).

Hereinafter, the relationship between the quantum dot 2100 and the chain molecule 2200 will be described. The relationship may include a positional relationship, a bonding relationship, and an optical relationship.

17 is a view showing the configuration of quantum dots and chain molecules included in a complex according to an embodiment. 11 to 17, the relationship between the quantum dot 2100 and the chain molecule 2200 will be described in detail.

The chain molecule 2200 may be attached to the quantum dot 2100. The chain molecule 2200 may be attached to a region of the quantum shell 2130 of the quantum dot 2100. One region of the chain molecule 2200 may be attached to the quantum dot 2100. One region of the chain molecule 2200 may be attached to one region of the quantum shell 2130 of the quantum dot 2100. One region of the chain molecule 2200 may be a whole region or a region of the head 2210. One region of the chain molecule 2200 may be a whole region or a region of the tail 2230.

One end of the chain molecule 2200 may be attached to the quantum dot 2100. One end of the chain molecule 2200 may be an end portion of the head 2210. One end of the chain molecule 2200 may be an end portion of the tail 2230.

Referring to FIG. 17(a), one end of the chain molecule 2200 may be attached between the adjacent ligands 2150. One end of the chain molecule 2200 may be attached to the region of the quantum dot 2100 between the adjacent ligands 2150. One end of the chain molecule 2200 may be attached to a region of the quantum dot 2100 where at least one of a plurality of ligands located on the surface of the quantum dot 2100 is removed.

Referring to (b) of FIG. 17, one end of the chain molecule 2200 may be attached to the ligand 2150. One end of the chain molecule 2200 may be attached to one region of the ligand 2150. One end of the chain molecule 2200 may be attached to the end of the ligand 2150.

The attachment may be by electrical attraction or chemical bonding. The electrical attraction may include Vanderwalls attraction, Coulomb's attraction, and the like. The chemical bond may include covalent bond, coordination bond, dipole-dipole action, and the like.

The chain molecule 2200 is attached to the quantum dot 2100, the dispersibility of the quantum dot 2100 in the complex 1010 may be improved. The chain molecule 2200 is attached to the quantum dot 2100, the dispersibility of the quantum dot 2100 in the quantum dot powder 1001 can be improved.

Hereinafter, the bead 2300 will be described. 18 is a view showing a bead 2300 included in a composite according to an embodiment. The beads 2300 will be described in detail with reference to FIGS. 11 to 18.

The bead 2300 may include a bead shell 310 and an inner space 2330 may be defined by the bead shell 2310. The bead shell 2310 may define an external shape of the bead 2300. The bead shell 2310 may be formed such that the external shape of the bead 2300 is a spherical shape.

The beads 2300 may have a predetermined size. The beads 2300 may have a size capable of separating a plurality of quantum dots 2100. The beads 2300 may have a size of 40 nm to 60 nm.

The bead shell 2310 may have predetermined optical characteristics. The light properties may include light transmittance and light scattering properties. The bead shell 2310 may transmit light incident to the bead shell 2310. The bead shell 2310 may be made of a material having high light transmittance. For example, the bead shell 2310 may be implemented with a silica-based material such as silicon oxide (SiO ₂ ). The bead shell 2310 may scatter light incident on the bead shell 2310. The bead shell 2310 may be implemented in various thicknesses depending on the purpose. For example, the bead shell 2310 may be formed with a thin thickness to improve light transmittance of the bead shell 2310. The bead shell 2310 may be formed in a thick thickness to improve the durability of the bead shell 2310. The bead shell 2310 may be formed to an appropriate thickness in consideration of the light transmittance and the durability at the same time.

The inner space 2330 may include a predetermined filler, but the inner space 2330 may be empty. The filler may be a material having high light transmittance. When the internal space 2330 is empty, it may be defined as a hollow-core state. In the case of the bead 2300 implemented in the hollow state, optical characteristics of the bead 2300 may be improved. When the bead 2300 includes a predetermined filler, light scattered through the bead shell 2310 may be blocked by the filler. On the other hand, in the case of the hollow bead 2300, light scattered in one region of the bead shell 2310 may be propagated without blocking in the bead 2300. The propagated light may be re-randomized in the other region of the bead shell 2310. The property scattered light may be output to the outside of the bead 2300. Accordingly, in the case of the hollow beads 2300, light scattering properties of the beads 2300 may be improved.

The configurations shown in FIG. 18 are not essential, and the bead 2300 having more or fewer components may be implemented. For example, the bead 2300 may further include a predetermined coating layer disposed on the bead shell 2310. The predetermined coating layer may be a layer formed to improve the optical properties of the bead 2300.

Hereinafter, the relationship between the quantum dots 2100, chain molecules 2200, and beads 2300 included in the complex 1010 will be described.

14 and 19 are views showing a configuration of a plurality of components included in a composite according to an embodiment. 11 to 19, the relationship between the quantum dots 2100, chain molecules 2200, and beads 2300 included in the complex 1010 will be described in detail.

The chain molecule 2200 may be located between the quantum dot 2100 and the bead 2300. The chain molecule 2200 may be attached to the quantum dot 2100 and the bead 2300.

Adjacent quantum dots 2100 are defined as first quantum dots 2101 and second quantum dots 2102, and the chain molecules 2200 may include first chain molecules 2201 and second chain molecules 2202. have. In this case, the first chain molecule 2201 may be attached to the first quantum dot 2101, and the second chain molecule 2202 may be attached to the second quantum dot 2102.

Referring to FIG. 4, the beads 2300 may be located between a plurality of adjacent chain molecules 2200. The bead 2300 may be located between the first chain molecule 2201 and the second chain molecule 2202. The beads 2300 may be positioned between other regions of the adjacent chain molecules 2200. The beads 2300 may be spaced apart between other regions of the adjacent chain molecules 2200. The other region may be defined as a region of the chain molecule 2200 except for one region attached to the quantum dot 2100 of the chain molecule 2200. A bead 2300 may be positioned between the other region of the first chain molecule 2201 and the other region of the second chain molecule 2202. A bead 2300 may be spaced apart between the other region of the first chain molecule 2201 and the other region of the second chain molecule 2202. Other regions of the adjacent chain molecules 2200 may be composed of the same chain molecules 2200. For example, when the other region of the first chain molecule 2201 is a head, the other region of the second chain molecule 2202 may be a head, and the other region of the first chain molecule 2201 may be a tail. In this case, the other region of the second chain molecule 2202 may be a tail. Other regions of the adjacent chain molecules 2200 may be composed of different chain molecules 2200.

The beads 2300 may be positioned between the other ends of the adjacent chain molecules 2200. The beads 2300 may be spaced apart between the other ends of the adjacent chain molecules 2200. The other end may be defined as an opposite portion of one end attached to the quantum dot 2100 of the chain molecule 2200. A bead 2300 may be positioned between the other end of the first chain molecule 2201 and the other end of the second chain molecule 2202. Beads 2300 may be positioned between the other end of the first chain molecule 2201 and the other end of the second chain molecule 2202. The other ends of the adjacent chain molecules 2200 may be composed of the same chain molecule 2200. For example, when the other end of the first chain molecule 2201 is a head, the other end of the second chain molecule 2202 may be a head, and when the other end of the first chain molecule 2201 is a tail, The other end of the second chain molecule 2202 may be a tail. The other end of the adjacent chain molecules 2200 may be composed of different chain molecules 2200.

Referring to FIG. 19, the beads 2300 may be attached to adjacent chain molecules 2200. The beads 2300 may be attached to the first chain molecule 2201 and the second chain molecule 2202. The bead 2300 may be attached to the other region or the other end of the first chain molecule 2201 and the other region or the other end of the second chain molecule 2202. The attachment may be by electrical attraction or chemical bonding. The electrical attraction may include Vanderwalls attraction, Coulomb's attraction, and the like. The chemical bond may include covalent bond, coordination bond, dipole-dipole action, and the like.

Adjacent quantum dots 2100 may be spaced apart. The adjacent quantum dots 2100 may be separated by at least one of the chain molecule 2200 and the bead 2300. The adjacent quantum dots 2100 may be separated by a chain molecule 2200 and the beads 2300 coupled to each quantum dot 2100. The plurality of quantum dots 2100 may have a predetermined physical gap by the chain molecule 2200 and the bead 2300. The physical spacing between the quantum dots 2100 may contribute to maintaining quantum efficiency and luminescence properties of the quantum dot powder 10.

Hereinafter, a configuration in which a plurality of the quantum dots 2100 included in the quantum dot powder 1001 are separated by the inorganic phosphor 1020 or the beads 2300 will be described.

20 and 21 are views illustrating a distance between a plurality of quantum dots included in a quantum dot powder according to an embodiment. With reference to FIGS. 11 to 21, the distance between the plurality of quantum dots 2100 will be described in detail.

Adjacent quantum dots 2100 are defined as first quantum dots 2101 and second quantum dots 2102, and the chain molecules 2200 may include first chain molecules 2201 and second chain molecules 2202. have. In this case, the first chain molecule 2201 may be attached to the first quantum dot 2101, and the second chain molecule 2202 may be attached to the second quantum dot 2102. The first quantum dot 2101 and the second quantum dot 2102 may be different quantum dots, for example, the first quantum dot 2101 may be a red quantum dot and the second quantum dot 2102 may be a green quantum dot. . In addition, the first chain molecule 2201 and the second chain molecule 2202 may also be different chain molecules.

Referring to FIG. 20, a plurality of adjacent quantum dots 2100 may be spaced apart. The adjacent quantum dots 2100 may be separated by the chain molecule 2200 and the inorganic phosphor 1020. The adjacent quantum dots 2100 may be separated by the chain molecule 2200 and the inorganic phosphor 1020 coupled to each quantum dot 2100. A distance may be formed between a plurality of adjacent quantum dots 2100, and a distance between the plurality of quantum dots 2100 may be defined as a first distance D1.

The adjacent plurality of quantum dots 2100 may be positioned spaced apart from each other by a first distance D1. The first quantum dot 2101 and the second quantum dot 2102 may be spaced apart from each other by a first distance D1. The surface of the first quantum dot 2101 and the surface of the second quantum dot 2102 may be positioned spaced apart from each other by the first distance D1. The center of the first quantum dot 2101 and the center of the second quantum dot 2102 may be positioned spaced apart from each other by the first distance D1.

The first distance D1 may be defined by an inorganic phosphor 1020 positioned around a plurality of adjacent quantum dots 2100 and chain molecules 400 attached to the quantum dots 2100. The first distance D1 may be proportional to the sum of the length of the chain molecule 2200 and the width A1 of the inorganic phosphor 1020. However, the first distance D1 may be smaller than the sum of the length of the chain molecule 2200 and the width A1 of the inorganic phosphor 1020 coupled between the respective quantum dots 2100. The first distance D1 is the width A1 of the inorganic phosphor 1020 positioned between the first quantum dot 2101 and the second quantum dot 2102, and the length L1 of the first chain molecule 2201 ), and the length of the second chain molecule 2202 (L2).

The adjacent chain molecules 2200 may form a predetermined angle. The first chain molecule 2201 and the second chain molecule 2202 attached to the inorganic phosphor 1020 may form a predetermined angle. The angle may be an acute angle.

The first distance D1 may be adjusted according to the length of the chain molecule 2200 and the width of the inorganic phosphor 1020. The distance between the plurality of quantum dots 2100 may be further spaced apart by increasing at least one of the length of the chain molecule 2200 and the width of the inorganic phosphor 1020. Therefore, the distance between the plurality of adjacent quantum dots 2100 may be greater in the quantum dot powder 1001 including the inorganic phosphor 1020 than in the quantum dot powder containing only the composite 1010.

Accordingly, a phenomenon in which a plurality of composites 1010 in the quantum dot powder 1001 aggregate with each other may be reduced. A phenomenon in which a plurality of quantum dots 2100 included in the composite 1010 in the quantum dot powder 1001 aggregate with each other may be reduced. When the inorganic phosphor 1020 is not included in the quantum dot powder 1001, a plurality of composites 1010 in the quantum dot powder 1001 may be in contact with each other. When the inorganic phosphor 1020 is not included in the quantum dot powder 1001, a plurality of quantum dots 2100 included in the complex 1010 in the quantum dot powder 1001 may be in contact with each other. The quantum dots 2100 that are in contact with each other may be aggregated and aggregated with each other, whereas in the case of the quantum dot powder 1001 including the inorganic phosphor 1020, a plurality of quantum dots 2100 are positioned to be spaced apart from each other to form a plurality of quantum dots 2100 ) Can reduce the phenomenon of agglomeration.

In addition, the luminous efficiency of the quantum dot powder 1001 including the inorganic phosphor 1020 may be improved. When the inorganic phosphor 1020 is not included in the quantum dot powder 1001, the quantum dots 2100 are aggregated with each other. Light output from the aggregated quantum dots 2100 may interfere with each other. The luminous efficiency of the quantum dot powder 1 including the aggregated quantum dots 2100 is deteriorated. On the other hand, when the inorganic phosphor 1020 is included in the quantum dot powder 1, as described above, the dispersibility of the quantum dots 2100 is increased. Accordingly, the interference phenomenon of light output from the quantum dots 2100 may be reduced. The light that does not interfere with each other may be output from the quantum dot powder (1). Accordingly, the luminous efficiency of the quantum dot powder 1 including the inorganic phosphor 1020 may be increased.

Referring to FIG. 21, a plurality of adjacent quantum dots 2100 may be spaced apart. The adjacent quantum dots 2100 may be separated by the chain molecule 2200 and the beads 2300. The adjacent quantum dots 2100 may be separated by the chain molecule 2200 and the beads 2300 coupled to each quantum dot 2100. A plurality of adjacent quantum dots 2100 may be formed, and a distance between the plurality of quantum dots 2100 may be defined as a second distance D2.

A plurality of adjacent quantum dots 2100 may be positioned spaced apart from each other by a second distance D2. The first quantum dot 2101 and the second quantum dot 2102 may be spaced apart from each other by a second distance D2. The surface of the first quantum dot 2101 and the surface of the second quantum dot 2102 may be spaced apart from each other by the second distance D2. The center of the first quantum dot 2101 and the center of the second quantum dot 2102 may be positioned spaced apart from each other by the second distance D2.

The second distance D2 may be defined by beads 2300 positioned around a plurality of adjacent quantum dots 2100 and chain molecules 400 attached to the quantum dots 2100. The second distance D2 may be proportional to the sum of the length of the chain molecule 2200 and the width A2 of the bead 2300. However, the second distance D2 may be smaller than the sum of the length of the chain molecule 2200 and the width A2 of the bead 2300 coupled between each quantum dot 2100. The second distance D2 is the width A2 of the bead 2300 positioned between the first quantum dot 2101 and the second quantum dot 2102, and the length L1 of the first chain molecule 2201 And, it may be determined based on the sum of the length (L2) of the second chain molecule (2202).

The adjacent chain molecules 2200 may form a predetermined angle. The first chain molecule 2201 and the second chain molecule 2202 attached to the bead 2300 may form a predetermined angle. The angle may be an acute angle.

The second distance D2 may be adjusted according to the length of the chain molecule 2200 and the width of the bead 2300. The distance between the plurality of quantum dots 2100 may be further spaced apart by increasing at least one of the length of the chain molecule 2200 and the width of the bead 2300. Accordingly, the distance between the plurality of adjacent quantum dots 2100 may be greater in the quantum dot powder 1001 including the beads 2300 than in the quantum dot powder containing only the quantum dots 2100.

Accordingly, a phenomenon in which a plurality of quantum dots 2100 included in the composite 1010 in the quantum dot powder 1001 aggregate with each other may be reduced. When the beads 2300 are not included in the quantum dot powder 1001, a plurality of composites 1010 in the quantum dot powder 1001 may be in contact with each other. When the beads 2300 are not included in the quantum dot powder 1001, a plurality of quantum dots 2100 included in the composite 1010 in the quantum dot powder 1001 may be in contact with each other. Quantum dots 2100 in contact with each other may be aggregated and aggregated with each other, whereas in the case of quantum dot powders 1001 including beads 2300, a plurality of quantum dots 2100 are spaced apart from each other to form a plurality of quantum dots 2100 It can reduce the phenomenon of agglomeration.

In addition, the luminous efficiency of the quantum dot powder 1001 including the beads 2300 may be improved. When the beads 2300 are not included in the quantum dot powder 1001, the quantum dots 2100 are aggregated with each other. Light output from the aggregated quantum dots 2100 may interfere with each other. The luminous efficiency of the quantum dot powder 1001 including the aggregated quantum dots 2100 decreases. In contrast, when the bead 2300 is included in the quantum dot powder 1, as described above, the dispersibility of the quantum dots 2100 is increased. Accordingly, the interference phenomenon of light output from the quantum dots 2100 may be reduced. The light that does not interfere with each other may be output from the quantum dot powder 1001. Accordingly, the luminous efficiency of the quantum dot powder 1001 including the beads 2300 may be increased.

20 and 21, a plurality of adjacent quantum dots 2100 may be spaced apart by at least one of the inorganic phosphor 1020 and the bead 2300. The adjacent plurality of quantum dots 2100 may be spaced apart by the inorganic phosphor 1020 and the beads 2300. The adjacent plurality of quantum dots 2100 may be spaced apart by the first distance D1 by the inorganic phosphor 1020 or spaced by the second distance D2 by the beads 2300. The adjacent plurality of quantum dots 2100 may be spaced apart by the first distance D1 by the inorganic phosphor 1020, and may be spaced apart by the beads 2300 by the second distance D2, respectively. have.

The first distance D1 may be greater than the second distance D2. The bead 2300 may be larger than the inorganic phosphor 1020. The inorganic phosphor 1020 has a size of 1um to 10um, while the bead 2300 may have a size of 40nm to 60nm. The width A1 of the inorganic phosphor 1020 may be greater than the width A2 of the bead 2300. The adjacent plurality of quantum dots 2100 may be spaced apart from at least one of the first distance D1 and the second distance D2, respectively. The adjacent plurality of quantum dots 2100 may be spaced apart by the first distance D1 and the second distance D2, respectively, and the adjacent plurality of quantum dots 2100 may be spaced apart from each other. . Since the first distance D1 is spaced apart from the second distance D2, the dispersibility of the adjacent plurality of quantum dots 2100 may be further improved. As described above, as the dispersibility of the plurality of quantum dots 2100 is improved, thermal stability of the quantum dot powder 1001 is improved, and quantum efficiency and luminescence properties can be maintained.

Hereinafter, a configuration in which a plurality of components included in the quantum dot powder 1001 are spaced apart will be described.

22 and 23 are views illustrating a distance between a plurality of components included in a quantum dot powder according to an embodiment. With reference to FIGS. 11 to 23, a description will be given of a distance between a plurality of the components.

The quantum dot powder 1001 may include adjacent complex 1010 and inorganic phosphor 1020, and the complex 1010 may include quantum dots 2100, chain molecules 2200, and beads 2300. It can contain. A plurality of chain molecules 2200 may be attached to the quantum dot 2100, and the plurality of chain molecules 2200 may be different materials from each other. A plurality of chain molecules 2200 may be attached to the quantum dot 2100, and the plurality of chain molecules 2200 may have different lengths.

The distance at which each of the inorganic phosphors 1020, quantum dots 2100, chain molecules 2200, and beads 2300 included in the quantum dot powder 1001 is located is the width A2 of the beads 2300 and the quantum dots ( It may be defined based on at least one of the width (A1) of the 2100), and the length (L) of the chain molecule 2200.

Referring to FIG. 22, the adjacent inorganic phosphor 1020 and the quantum dot 2100 may be positioned spaced apart from each other. A distance may be formed between the adjacent inorganic phosphors 1020 and the quantum dots 2100, and the distance between the inorganic phosphors 1020 and the quantum dots 2100 may be defined as a third distance D3. The inorganic phosphor 1020 and the quantum dot 2100 may be positioned spaced apart from each other by a third distance D3. The surface of the inorganic phosphor 1020 and the surface of the quantum dot 2100 may be positioned spaced apart from each other by the third distance D3. The center of the inorganic phosphor 1020 and the center of the quantum dot 2100 may be positioned spaced apart from each other by the third distance D3.

The third distance D3 may be defined by a bead 2300 positioned between the quantum dot 2100 and the inorganic phosphor 1020 and a chain molecule 2200 attached to the quantum dot 2100. The third distance D3 may be proportional to the sum of the length L of the chain molecule 2200 and the width A2 of the beads. However, the third distance D3 may be smaller than the sum of the length L of the chain molecule 2200 coupled to the quantum dot 2100 and the width A2 of the bead 2300.

The chain molecule 2200 bound to the quantum dot 2100 may form a predetermined angle based on a line connecting the center of the bead 2300 and the inorganic phosphor 1020. The angle may be an acute angle.

The third distance D3 may be adjusted according to the length L of the chain molecule 2200 and the width A2 of the bead 2300. The distance between the inorganic phosphor 1020 and the quantum dot 2100 may be further spaced by increasing at least one of the length L of the chain molecule 2200 and the width of the bead 2300.

Accordingly, a plurality of the quantum dots 2100 may be spaced apart by the inorganic phosphor 1020 and the beads 2300. Compared to the quantum dot powder containing only the beads 2300, the quantum dot powder 1001 including the inorganic phosphor 1020 and the beads 2300 may increase a distance in which a plurality of the quantum dots 2100 are separated. . As described above, in the quantum dot powder 1001 including the inorganic phosphor 1020 and the bead 2300, the distance between the plurality of quantum dots 2100 is increased, thereby dispersing the quantum dots 2100. Can be improved.

Referring to FIG. 23, the adjacent inorganic phosphor 1020 and the beads 2300 may be spaced apart from each other. A distance may be formed between the adjacent inorganic phosphor 1020 and the bead 2300, and the distance between the inorganic phosphor 1020 and the bead 2300 may be defined as a fourth distance D4. The inorganic phosphor 1020 and the bead 2300 may be positioned spaced apart from each other by a fourth distance D4. The surface of the inorganic phosphor 1020 and the surface of the bead 2300 may be positioned spaced apart from each other by the fourth distance D4. The center of the inorganic phosphor 1020 and the center of the bead 2300 may be positioned spaced apart from each other by the fourth distance D4.

The fourth distance D4 may be defined by a quantum dot 2100 positioned between the inorganic phosphor 1020 and the bead 2300 and a chain molecule 2200 attached to the quantum dot 2100. At least one of the plurality of chain molecules 2200 attached to the quantum dot 2100 may extend toward the inorganic phosphor 1020, and the plurality of chain molecules 2200 attached to the quantum dot 2100 At least one of the) may extend toward the bead 2300.

The fourth distance D4 may be proportional to the sum of the length L of the plurality of chain molecules 2200 and the width A3 of the quantum dots. However, the fourth distance D4 may be smaller than the sum of the length L of the plurality of chain molecules 2200 coupled to the quantum dot 2100 and the width A3 of the quantum dot 2100.

The adjacent chain molecules 2200 may form a predetermined angle. The chain molecules 2200 attached to the quantum dot 2100 may form a predetermined angle. The angle may be an acute angle.

The fourth distance D4 may be adjusted according to the length L of the plurality of chain molecules 2200 and the width A3 of the quantum dots 2100. The distance between the inorganic phosphor 1020 and the bead 2300 may be further separated by increasing at least one of the length (L) of the plurality of chain molecules 2200 and the width (A3) of the bead 2300. have.

Accordingly, a plurality of the quantum dots 2100 may be spaced apart by the inorganic phosphor 1020 and the beads 2300. Compared to the quantum dot powder containing only the beads 2300, the quantum dot powder 1001 including the inorganic phosphor 1020 and the beads 2300 has a plurality of the quantum dots 2100, the inorganic phosphor 1020 and the Beads 2300 may be spaced apart from each other. As described above, in the quantum dot powder 1001 including the inorganic phosphor 1020 and the bead 2300, a distance at which the plurality of quantum dots 2100 are spaced is varied, so that the dispersibility of the plurality of quantum dots 2100 is This can be improved more.

11 to 21, a plurality of the complexes 1010 and the inorganic phosphors 1020 included in the quantum dot powder 1001 may be spaced apart. The plurality of composites 1010 included in the quantum dot powder 1001 may be spaced apart by the inorganic phosphor 1020. Each of the plurality of composites 1010 and the inorganic phosphor 1020 is at least one of the first distance D1, the second distance D2, the third distance D3, and the fourth distance D4, respectively. It can be spaced one distance away. In addition, the quantum dot 2100 and the bead 2300 and the inorganic phosphor 1020 included in the composite 1010 may be spaced apart. The quantum dot 2100, the bead 2300, and the inorganic phosphor 1020 included in the composite 1010 are the first distance D1, the second distance D2, and the third distance, respectively. (D3), at least one of the fourth distances D4 may be spaced apart.

Accordingly, when it is determined based on the quantum dot 2100, the plurality of quantum dots 2100 included in the complex 1010 may be separated by the chain molecule 2200 and the bead 2300. In addition, a plurality of the complex 1010 may be spaced apart by the inorganic phosphor 1020, so that the plurality of quantum dots 2100 included in the complex 1010 may also be spaced apart by the inorganic phosphor 1020. can. Accordingly, the bead 2300 may disperse a plurality of the quantum dots 2100 within a relatively narrow range based on the quantum dots 2100, and at the same time, the inorganic phosphor 1020 may have a plurality of within a relatively wide range. The quantum dots 2100 may be dispersed. Therefore, the degree of dispersion of the plurality of quantum dots 2100 included in the quantum dot powder 1001 may be determined according to the size or width of the beads 2300 and the inorganic phosphor 1020. The dispersion degree of the plurality of quantum dots 2100 included in the quantum dot powder 1001 is the first distance D1, the second distance D2, the third distance D3, and the fourth distance ( D4), the degree of dispersion of the plurality of quantum dots 2100 may be more varied than the quantum dot powder containing only beads. As described above, as the dispersibility of the plurality of quantum dots 2100 is improved, thermal stability of the quantum dot powder 1001 is improved, and quantum efficiency and luminescence properties can be maintained.

Hereinafter, various positional relationships of a plurality of components included in the quantum dot powder 1001 will be described.

24 is a view showing an SEM image of a quantum dot powder according to an embodiment. 25 is a TEM image of a composite included in a quantum dot powder according to an embodiment, and FIG. 26 is a view showing a TEM image of FIG. 25 enlarged.

27 to 32 are diagrams illustrating a configuration of a plurality of components included in the quantum dot powder according to an embodiment.

24 to 26, a plurality of the complexes 1010 included in the quantum dot powder 1001 may be dispersed and positioned by the inorganic phosphor 1020. In addition, a plurality of the quantum dots 2100 included in the complex 1010 may be dispersed and positioned by the chain molecule 2200 and the beads 2300.

Referring to FIG. 27, the inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned between a plurality of the complexes 1010. The inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned adjacently between a plurality of the complexes 1010. The complex 1010 and the inorganic phosphor 1020 included in the quantum dot powder 1001 may be spaced apart by a predetermined distance. In addition, the quantum dot 2100 and the bead 2300 included in the composite 1010 may be positioned spaced apart from the inorganic phosphor 1020. The quantum dot 2100 and the bead 2300 included in the complex 1010 may be spaced apart. The quantum dot 2100 and the bead 2300 included in the composite 1010 may be spaced apart by a predetermined distance.

Referring to FIG. 28, the inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned between a plurality of the complexes 1010. The inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned adjacently between a plurality of the complexes 1010. The bead 2300 included in the composite 1010 may contact the composite 1010 and the inorganic phosphor 1020. The quantum dot 2100 and the bead 2300 included in the complex 1010 may be spaced apart. The quantum dot 2100 and the bead 2300 included in the composite 1010 may be spaced apart by a predetermined distance.

Referring to FIG. 29, the inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned between a plurality of the composites 1010. The inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned adjacently between a plurality of the complexes 1010. The quantum dot 2100 included in the complex 1010 may contact the complex 1010 and the inorganic phosphor 1020. The chain molecule 2200 attached to the quantum dot 2100 included in the complex 1010 may contact the inorganic phosphor 1020. The quantum dot 2100 and the bead 2300 included in the complex 1010 may be spaced apart. The quantum dot 2100 and the bead 2300 included in the composite 1010 may be spaced apart by a predetermined distance.

Referring to FIG. 30, the inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned between a plurality of the composites 1010. The inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned adjacently between a plurality of the complexes 1010. The complex 1010 and the inorganic phosphor 1020 included in the quantum dot powder 1001 may be spaced apart by a predetermined distance. In addition, the quantum dot 2100 and the bead 2300 included in the composite 1010 may be positioned spaced apart from the inorganic phosphor 1020. The quantum dot 2100 and the bead 2300 included in the composite 1010 may be positioned in contact. The chain molecule 2200 attached to the quantum dot 2100 included in the complex 1010 may be located in contact with the bead 2300.

Referring to FIG. 31, the inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned between a plurality of the complexes 1010. The inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned adjacently between a plurality of the complexes 1010. The composite 1010 included in the quantum dot powder 1001 and the inorganic phosphor 1020 may contact each other. The inorganic phosphor 1020 may be in contact with the bead 2300 included in the composite 1010. The quantum dot 2100 and the bead 2300 included in the composite 1010 may be positioned in contact. The chain molecule 2200 attached to the quantum dot 2100 included in the complex 1010 may be located in contact with the bead 2300.

Referring to FIG. 32, the inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned between a plurality of the complexes 1010. The inorganic phosphor 1020 included in the quantum dot powder 1001 may be positioned adjacently between a plurality of the complexes 1010. The composite 1010 included in the quantum dot powder 1001 and the inorganic phosphor 1020 may contact each other. The inorganic phosphor 1020 may contact the quantum dot 2100 included in the composite 1010. The chain molecule 2200 attached to the quantum dot 2100 included in the complex 1010 may contact the inorganic phosphor 1020. The quantum dot 2100 and the bead 2300 included in the composite 1010 may be positioned in contact. The chain molecule 2200 attached to the quantum dot 2100 included in the complex 1010 may be located in contact with the bead 2300.

Accordingly, a plurality of components included in the quantum dot powder 1001 may be arranged through various positional relationships. The plurality of components included in the quantum dot powder 1001 may be variously arranged through various contact relationships. The plurality of components included in the quantum dot powder 1001 may be variously arranged as they are separated by a predetermined distance. The plurality of composites 1010 included in the quantum dot powder 1001 may be variously disposed by the inorganic phosphor 1020, and accordingly, the plurality of composites 1010 may be dispersed and positioned. The plurality of quantum dots 2100 included in the complex 1010 may be variously arranged by the chain molecule 2200 and the beads 2300, and accordingly, the plurality of complex 1010 are dispersed with each other Can be located. Overall, the plurality of quantum dots 2100 included in the quantum dot powder 1001 are spaced apart by at least one of the inorganic phosphor 1020, the chain molecule 2200, and the beads 2300, the tactics As described above, as the dispersibility of the plurality of quantum dots 2100 is improved, thermal stability and light emission characteristics may be improved.

Hereinafter, effects obtained by improving the dispersibility of the plurality of quantum dots included in the quantum dot powder 1001 will be described.

33 is a view showing an effect of a distance between a plurality of quantum dots in a quantum dot powder according to an embodiment on a quantum dot powder.

A plurality of the quantum dots may be defined to include a first quantum dot 2101 and a second quantum dot (2102).

A plurality of the quantum dots may have active electrons when a predetermined energy is applied. The active electrons can be exchanged between adjacent quantum dots, resulting in fluorescence resonance energy transfer (FRET). The transfer rate (exchange rate) of the active electrons may be inversely proportional to the distance between the plurality of quantum dots. The active electrons delivered are not used for light emission. When the active electrons are delivered, the transferred active electrons can be reduced to light. Light loss may occur in the quantum dot powder 1001 as the transferred active electrons cannot be reduced to light. On the other hand, as the distance between the plurality of quantum dots increases, it is possible to reduce the optical loss of the quantum dot powder 1001 by suppressing the transmission of the active transfer.

Referring to FIG. 33, when the distance between the first quantum dot 2101 and the second quantum dot 2102 is close, light loss may occur in the quantum dot powder 1001. On the other hand, when the distance between the first quantum dot 2101 and the second quantum dot 2102 is far, as described above, the light loss in the quantum dot powder 1001 may be reduced. As the distance between the first quantum dot 2101 and the second quantum dot 2102 increases, the first quantum dot 2101 and the second quantum dot 2102 cannot exchange active electrons with each other. That is, the transfer rate of the active electrons in the quantum dot powder 1001 may be maintained in a low state. In the case of the present invention, a plurality of the quantum dots 2100, the inorganic phosphor 1020, the chain molecule 2200, and the dispersibility can be improved as they are separated by at least one of the beads 2300, According to the improved dispersibility, an active electron transfer rate may be maintained in a low state. Accordingly, the quantum dot powder (1001) of the present invention can maintain high quantum efficiency and luminescence properties, heat and moisture stability is very high, it may not change even when exposed to the atmosphere.

The quantum dot powder may include the first quantum dot powder and the second quantum dot powder. The first quantum dot powder or the second quantum dot powder may include the components illustrated in FIGS. 11 to 33, but the components illustrated in FIGS. 11 to 33 are not essential components, and illustrated in FIGS. 11 to 33 The quantum dot powder having more or less than the configured configuration may be implemented.

For example, the first quantum dot powder or the second quantum dot powder included in the first wavelength conversion layer 301 or the second wavelength conversion layer 401 of the backlight unit 1 is the quantum dot 2100. , May include at least one of the chain molecule 2200, the bead 2300, and the inorganic phosphor 1020, and may be a quantum dot powder having more or less components than the plurality of components.

Hereinafter, stability according to the ratio of the quantum dot 2100 and the inorganic phosphor 20 included in the quantum dot powder 1001 will be described in detail.

34 to 39 are views showing acceleration life measurement results according to a ratio of quantum dots and inorganic phosphors included in a quantum dot powder according to an embodiment. 30 is a view showing a peak comparison result according to a ratio of quantum dots and inorganic phosphors included in a quantum dot powder according to an embodiment.

Based on the ratio of the quantum dot 2100 and the inorganic phosphor 1020 included in the quantum dot powder 1001, (1) Figure 34 is the case where only the quantum dot 2100 is included (2) Figure 25 is the inorganic When only the phosphor 100 is included, (3) FIG. 35 shows the quantum dot 2100 versus the inorganic phosphor 1020 is 1:50, and (4) FIG. 36 shows the quantum dot 2100 versus the inorganic phosphor ( 1020) is 1:5, (5) Figure 37 is the quantum dot 2100 to the inorganic phosphor 1020 is 2:5, (6) Figure 38 is the quantum dot 2100 to the inorganic phosphor ( 1020) is a result corresponding to the case of 3:5. The ratio may be a mass or volume ratio of the quantum dot 2100 and the inorganic phosphor 1020 included in the quantum dot powder 1001. In addition, the ratio may be a ratio with respect to the mass or volume of the quantum dot 2100 and the inorganic phosphor 2 compared to the solvent contained in the quantum dot solution forming the quantum dot powder 1001.

34 to 39 are results obtained by confirming a film by using a quantum dot powder according to each ratio of the quantum dot 2100 and the inorganic phosphor 1020. The above result is a result of measuring the acceleration life using a blue LED and a temperature. The factors used to obtain the accelerated life measurement results are blue LED flux (125 mW/cm ² , 16 times) and temperature (80°C, 2.8 times), and the total acceleration factor is 44.8 times.

Referring to FIG. 34, in the case of the quantum dot powder 1001 containing only the quantum dot 2100, the initial luminous efficiency of the quantum dot powder 1001 is excellent, but the luminous efficiency of the quantum dot powder 1001 is relatively sharply decreased. You can confirm that. In contrast, referring to FIG. 35, in the case of the quantum dot powder 1001 containing only the inorganic phosphor 1020, the initial luminous efficiency of the quantum dot powder 1001 is not superior to that of FIG. 34, but the quantum dot powder ( It can be seen that the luminous efficiency of 1001) is relatively stable. Therefore, it can be seen that when the inorganic phosphor 1020 is included in the quantum dot powder 1001, it affects the stability of the luminous efficiency of the quantum dot powder 1001. However, when only the inorganic phosphor 1020 is included, it is necessary to properly adjust the ratio of the quantum dots 2100 and the inorganic phosphors 1020 in consideration of the relatively low initial emission efficiency of the quantum dot powder 1001. have.

Referring to FIG. 36, in the case of the quantum dot powder 1001 in which the quantum dot 2100 versus the inorganic phosphor 1020 is 1:50, stability is greatly improved by the inorganic phosphor 1020, but when compared with FIG. 35. It can be seen that the luminous efficiency of the quantum dot powder 1001 is almost the same. On the other hand, referring to FIG. 37, when the quantum dot 2100 to the inorganic phosphor 1020 is 1:5, stability is improved by the inorganic phosphor 1020 and initial light emission of the quantum dot powder 1001 It can be seen that the efficiency is relatively high. In addition, referring to FIG. 38, when the quantum dot 2100 to the inorganic phosphor 1020 is 2:5, the initial luminous efficiency of the quantum dot powder 1001 is relatively high compared to FIGS. 35 to 37. It is almost similar to, but the stability by the inorganic phosphor 1020 can be seen to be improved compared to FIG. 24 although relatively inferior to FIGS. 35 to 37. In addition, referring to FIG. 39, when the quantum dot 2100 to the inorganic phosphor 1020 is 3:5, the initial luminous efficiency of the quantum dot powder 1001 is relatively high compared to FIGS. 35 to 38. It becomes almost similar to, but the stability by the inorganic phosphor 1020 can be seen to be improved compared to FIG. 34, although relatively inferior to FIGS. 35 to 38. Therefore, as the ratio of the quantum dot 2100 and the inorganic phosphor 1020 included in the quantum dot powder 1001 is adjusted, the luminous efficiency by the quantum dot 2100 is improved and the stability by the inorganic phosphor 1020 The effect of the improvement can be adjusted.

Referring to FIG. 37, a result of comparing peaks according to ratios of the quantum dots 2100 and the inorganic phosphor 1020 included in the quantum dot powder 1001 may be confirmed. Referring to FIG. 37, based on the quantum dot powder 1001 containing only the inorganic phosphor 1020, the peak of the quantum dot powder 1001 moves to the right as the proportion of the quantum dot 2100 increases It can be seen that the peak of the quantum dot powder 1001 containing only the quantum dot 2100 is similar.

In consideration of the analysis according to the above-described results and its effects, while having an effect of improving stability by the inorganic phosphor 1020, an appropriate ratio that can have an effect of improving the luminous efficiency by the quantum dot 2100 is the quantum dot ( 2100) vs. the inorganic phosphor 1020 may be 1 to 3:5. However, as the case having a peak position and intensity similar to the luminous efficiency of the quantum dot powder 1001 containing only the quantum dot 2100 and simultaneously improving the stability by the inorganic phosphor 1020, the quantum dot 2100 ) To the most suitable ratio of the inorganic phosphor 1020 may be 2 to 3:5.

When the ratio of the quantum dots 2100 to the inorganic phosphors 1020 is less than 1:5, the ratio of the inorganic phosphors 1020 is relatively large, so that a half width of the peak is large, but the position of the peak includes only the quantum dots 2100. It can be seen that the quantum dot powder is located on the left side compared to the case. This means that the wavelength of light applied to the quantum dot powder in which the ratio of the quantum dots 2100 to the inorganic phosphor 1020 is less than 1:5 is converted to a lower wavelength than the quantum dot powder containing only the quantum dots 2100. This may affect the luminous efficiency of the quantum dot powder 1001. The quantum dot powder in the case where the ratio of the quantum dots 2100 to the inorganic phosphor 1020 is less than 1: 5 may require more quantum dot powders to produce luminous efficiency, such as the quantum dot powder containing only the quantum dots 2100. . Due to this, the unit price for producing a quantum dot film that exhibits the same luminous efficiency may be expensive.

In addition, when the ratio of the quantum dots 2100 to the inorganic phosphor 1020 is greater than 3:5, considering the tendency of FIG. 40, the ratio of the quantum dots 2100 is relatively large, and the position and intensity of the peaks are quantum dots ( 2100) will be similar to the quantum dot powder containing only. However, as the proportion of the quantum dots 2100 increases compared to the inorganic phosphor 1020, when considering FIGS. 34 to 39, the effect of improving stability by the inorganic phosphor 1020 may be deteriorated. Therefore, even if the ratio of the group quantum dot 2100 to the inorganic phosphor 1020 is greater than 3:5, the quantum dot powder has good luminous efficiency, but the thermal stability is poor and the luminous efficiency can be maintained only in a short time.

Hereinafter, the quantum efficiency of the quantum dot powder 1001 will be described.

In comparing the quantum efficiency, (1) a film made of a quantum dot solution, (2) a film made of a quantum dot powder containing no inorganic phosphor, and (3) a film made of a quantum dot powder containing inorganic phosphor I want to.

First, in the case of a film made of the quantum dot solution, the quantum dot solution having a concentration of 20mg/ml is dispersed in PDMS at a rate of 5wt%, coated with a thickness of 120um using a bar coating machine, and 20 minutes at 60°C. After drying, it can be produced by drying at 80° C. for 100 minutes. In addition, in the case of a film made of the quantum dot powder that does not contain an inorganic phosphor, after dispersing the quantum dot powder in a proportion of 5wt% in PDMS, the film can be prepared as in the case of a film made of the quantum dot solution. In addition, in the case of a film made of the quantum dot powder containing no inorganic phosphor, after dispersing the quantum dot powder containing 2.5wt% of the quantum dot and 2.5wt% of the inorganic phosphor in PDMS, the film produced by the quantum dot solution As in the case of a film can be produced.

Quantum efficiency can be defined as the ratio of photons or electrons converted to photons or electrons of different energy in the quantum dot powder or solution. The film of (1) has a quantum efficiency of 30 to 40%, the film of (2) has a quantum efficiency of 50 to 60%, preferably a film of 57%, and the film of (3) has 60% or more , Preferably it was confirmed to have a quantum efficiency of 71%.

In the film including the quantum dot 2100, when the quantum efficiency of the film is 60% or less, it is necessary to apply more quantum dots 2100 to increase the quantum efficiency. That is, in order to manufacture a quantum dot film having a high quantum efficiency, more quantum dot solutions or powders must be used, which may increase the manufacturing cost of the quantum dot film. However, when the quantum efficiency of the film is 60% or more, high quantum efficiency can be obtained even with a smaller amount of quantum dot solution or powder, thereby lowering the manufacturing cost of the quantum dot film. Therefore, the quantum dot powder of the present invention can have a high quantum efficiency as it further includes an inorganic phosphor 1020, and the manufacturing cost of the quantum dot film using the same can be lowered.

Accordingly, it can be seen that the quantum efficiency of the film made of the quantum dot powder is higher than that of the film produced by the quantum dot solution, and the quantum efficiency of the powder additionally containing an inorganic phosphor is higher in the film made of the quantum dot powder. Therefore, a film made of a quantum dot powder containing an inorganic phosphor has a relatively high quantum efficiency and a very high thermal stability. In addition, it can be seen that the film made of a quantum dot powder containing an inorganic phosphor maintains the quantum efficiency for a relatively long time. This may be determined that the quantum dot powder containing the inorganic phosphor is improved in dispersibility as the plurality of composites 1010 are separated by the inorganic phosphor 1020. Therefore, compared to the 1:1 ratio (quantum dot: inorganic phosphor) of the quantum dot powder used in the experiment, it can be predicted that the more the inorganic phosphor is included, the higher the quantum efficiency will be. Through this, the present invention can produce a quantum dot powder having a very high quantum efficiency.

Hereinafter, the color rendering index (CRI) of the quantum dot powder 1001 will be described.

Referring to Table 3, changes in color rendering index of the quantum dot powder 1001 including the quantum dot 2100 to the inorganic phosphor 1020 in 1:1 may be confirmed over time.

QD Powder
(1:1) 0
hr +72
hr +140
hr +232
hr +496
hr +568
hr +640
hr +730
hr +802
hr +895
hr +969
hr +1062
hr CRI 91 94.1 94 93.8 93.4 93.2 93 93 93.1 92.8 92.4 92.2

The color rendering index (CRI) may be defined as a numerical value for how similar the light converted from the quantum dot powder is. It can be seen that the color rendering index of the quantum dot powder 1001 containing the quantum dot 2100 versus the inorganic phosphor 1020 in 1:1 is changed to within 10% even after a time of about 1000hr or more has elapsed. This may be determined that the quantum dot powder containing the inorganic phosphor is improved in dispersibility as the plurality of composites 1010 are separated by the inorganic phosphor 1020. Therefore, compared to the 1:1 ratio (quantum dot: inorganic phosphor) of the quantum dot powder used in the experiment, it can be predicted that the more the inorganic phosphor is included, the longer the color rendering index will be maintained. Through this, the present invention can produce a quantum dot powder whose color rendering index is maintained for a long time within a range of 10% or less.

When the color rendering index of the quantum dot powder is not maintained within an error range of 10%, the life of the quantum dot powder may be shortened. When the color rendering index of the quantum dot powder is not maintained within an error range of 10%, the thermal stability of the quantum dot powder is low, and the concentration may be changed. On the other hand, when the color rendering index of the quantum dot powder is maintained within an error range within 10%, the life of the quantum dot powder may be prolonged. In addition, when the color rendering index of the quantum dot powder is maintained within an error range within 10%, the thermal stability of the quantum dot powder is high, and the concentration can be maintained.

The quantum dot powder 1001 having the above-described effect can be easily applied to a backlight unit including the quantum dot 2100 compared to a quantum dot solution. The quantum dot powder 1001 has high thermal stability and phase stability, and may be laminated on a reflective film or a diffusion film without a barrier film in the backlight unit. The quantum dot powder (1001) has a high thermal stability and phase stability, the thickness of the backlight unit may be reduced as it is integrally laminated on a reflective film or a diffusion film without a barrier film in the backlight unit. In addition, through the high thermal stability and phase stability of the quantum dot powder, as the barrier film is removed in the backlight unit, the unit cost due to the barrier film can be reduced, and the manufacturing process can be simplified.

As described above, although the embodiments have been described by a limited embodiment and drawings, those skilled in the art can make various modifications and variations from the above description. For example, the described techniques are performed in a different order than the described method, and/or the components of the described system, structure, device, circuit, etc. are combined or combined in a different form from the described method, or other components Alternatively, even if replaced or substituted by equivalents, appropriate results can be achieved.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

1: backlight unit
2: Conventional backlight unit
10: light source
20: light guide member
30: reflective conversion film
40: diffusion conversion film
50: panel

Claims (17)

Light source;
A light guide member for guiding light output from the light source;
A reflection conversion film disposed under the light guide member; And
And a diffusion conversion film disposed on the light guide member,
The reflection conversion film is a film on which a first wavelength conversion layer including a first wavelength conversion material is stacked and positioned on one surface of a reflection film,
The diffusion conversion film is a film on which a second wavelength conversion layer including a second wavelength conversion material is stacked and positioned on one surface of the diffusion film,
The first wavelength converting material and the second wavelength converting material each include at least one of a first quantum dot powder and a second quantum dot powder,
The reflection conversion film converts a first light having the same spectrum as that of the light output from the light source, and outputs a second light having a spectrum different from the first light in the direction of the light guide member,
The diffusion conversion film converts at least a portion of the first light and the second light to output a third light having a spectrum different from the first light and the second light,
The first light to the third light are mixed and output,
Backlight unit.
According to claim 1,
The light source is disposed on the side of the light guide member,
The first light is irradiated from the light source to the first wavelength conversion layer or the second wavelength conversion layer by the light guide member,
Backlight unit.
According to claim 1,
In the spectrums of the first light to the third light, areas in which peaks appear correspond to each other, and the intensity of the peaks differs in at least one area among areas in which the peaks appear.
Backlight unit.
According to claim 1,
In the reflection conversion film and the diffusion conversion film, each of the first wavelength conversion layer and the second wavelength conversion layer is disposed adjacent to the light guide member,
Backlight unit.
According to claim 1,
The reflection conversion film and the diffusion conversion film are each spaced apart from the light guide member,
Backlight unit.
The method of claim 5,
An air gap is formed between at least one of the reflection conversion film and the diffusion conversion film and the light guide member,
The first wavelength conversion layer or the second wavelength conversion layer of the reflection conversion film or the diffusion conversion film forming the air gap is exposed to the air gap,
Backlight unit.
According to claim 1,
The first wavelength conversion material of the reflection conversion film includes the first quantum dot powder,
The second wavelength conversion material of the diffusion conversion film comprises the second quantum dot powder,
Backlight unit.
According to claim 1,
The light source emits light in a first wavelength region,
The first quantum dot powder converts and outputs at least a portion of light in the first wavelength region into light in the second wavelength region,
The second quantum dot powder converts and outputs at least a portion of light in the first wavelength region into light in the third wavelength region,
The first wavelength region, the second wavelength region, and the third wavelength region are different, but at least a portion of each region overlaps,
Backlight unit.
According to claim 1,
The first quantum dot powder includes a plurality of first quantum dots, a first chain molecule, and a first bead,
The second quantum dot powder includes a plurality of second quantum dots, a second chain molecule, and a second bead,
Backlight unit.
The method of claim 9,
Each of the plurality of first quantum dots and the plurality of second quantum dots includes a quantum core, a quantum shell surrounding the quantum core, and a ligand formed on the surface of the quantum shell,
The first chain molecule includes one end and the other end attached to the plurality of first quantum dots, and the second chain molecule includes one end and the other end attached to the plurality of second quantum dots,
The first bead is positioned between the other ends of the plurality of first chain molecules, and the second bead is located between the other ends of the plurality of second chain molecules,
Backlight unit.

The method of claim 9,
The first beads are spaced apart from the other ends of the plurality of first chain molecules, the second beads are spaced apart from the other ends of the plurality of second chain molecules,
Backlight unit.
The method of claim 9,
Each of the plurality of first quantum dots and the plurality of second quantum dots converts light applied from the light source into a different spectrum and outputs the same.
Backlight unit.

According to claim 1,
The first quantum dot powder includes a plurality of first composites and a first inorganic phosphor,
The second quantum dot powder includes a plurality of second composite and a second inorganic phosphor,
Backlight unit.
The method of claim 13,
The first inorganic phosphor is located between the plurality of first composites, and the second inorganic phosphor is located between the plurality of second composites,
Backlight unit.
The method of claim 13,
The plurality of first complexes are positioned spaced apart from the first inorganic phosphor, and the plurality of second complexes are spaced apart from the second inorganic phosphor,
Backlight unit.
The method of claim 13,
The plurality of first complexes include a plurality of first quantum dots, a first chain molecule, and a first bead, and the plurality of second complexes include a plurality of second quantum dots, a second chain molecule, and a second bead. doing,
Backlight unit.

Bottom cover;
A support main fastened to the bottom cover; And
It includes a backlight unit disposed between the bottom cover and the support main,
The backlight unit includes a light source; A light guide member for guiding light output from the light source; A reflection conversion film disposed under the light guide member; And a diffusion conversion film disposed on the light guide member, wherein the reflection conversion film is a film on which a first wavelength conversion layer including a first wavelength conversion material is stacked and positioned on one surface of a reflection film, and the diffusion The conversion film is a film on which a second wavelength conversion layer including a second wavelength conversion material is stacked and positioned on one surface of a diffusion film, wherein the first wavelength conversion material and the second wavelength conversion material are the first quantum dot powder and the second Each of at least one of quantum dot powder, and the reflection conversion film converts a first light equal to a spectrum of light output from the light source, so that a second light having a spectrum different from the first light is directed to the light guide member Output, and the diffusion conversion film converts at least a portion of the first light and the second light to output a third light having a spectrum different from the first light and the second light, and the first light To the third light is mixed and output,
Display device.

Images