KR20180013129A - Wavelength-selective nanoporous structure - Google Patents

Abstract

The present invention relates to a wavelength-selective nanoporous structure which comprises: a nanoporous body in which a plurality of pores are formed; a nano-phosphor sealed in the pore; and a reflection unit formed on the inner surface of the pore for modulating an effective refractive index to selectively reflect light relative to an optical wavelength of the nano-phosphor. According to the present invention, by easily fabricating the wavelength-selective nanoporous structure, an application rage of an optical element may be broadened, an optical efficiency of the optical element can be increased, oxygen, moisture, and heat are intercepted to minimize influence and increase lifetime and durability of quantum dots, a loss of energy can be minimized, the reliability of an operation can be increased, manufacturing cost can be reduced, and deterioration of durability due to thermal damage can be prevented by excellent heat dissipation effects.

Description

Wavelength-selective nanoporous structure < RTI ID = 0.0 >

The present invention relates to a wavelength selective nanoporous structure, and more particularly, to a nanoporous nanoporous structure capable of increasing light efficiency of an optical element due to various optical characteristics due to its structure, The present invention relates to a wavelength selective nanoporous structure capable of significantly increasing the lifetime and durability of an optical element and further having an excellent heat radiation effect.

In general, a combination of three primary colors, in which white light generated from a light source is transmitted through red, green, and blue color filters, is used to realize various colors. As a white light source for this purpose, color conversion members using nano-phosphors such as quantum dots are commonly used.

Conventionally, as a light emitting technique using quantum dots, Korean Patent Laid-Open No. 10-2015-0133790 discloses "quantum dots in an encapsulated porous particle", which disclose that luminescent quantum dots are formed of a polymer material embedded in inorganic porous particles, Lt; RTI ID = 0.0 > porous < / RTI >

However, this conventional technique has a limitation in increasing the light utilization efficiency that is reflected forward. In addition to the conventional techniques, quantum dots exhibit excellent characteristics in comparison with the light conversion efficiency and color purity of existing phosphors in a conventional light emitting device using quantum dots, but they have some weaknesses. That is, quantum dots are denatured to heat, moisture, oxygen, and intense light, and their optical characteristics are greatly degraded with time. In addition, the currently known high-efficiency quantum dots are cadmium semiconductors, which are included in the RoHS (Restriction of Hazardous Substances) directive (RoHS), and are subject to high environmental regulations.

In order to solve such a problem, the present applicant has proposed a method of forming a nanoporous structure such as anodic alumina in a patent (Korean Patent Application No. 10-2015-0121727 and Korean Patent Application No. 10-2015-0172864) filed in the Korean Intellectual Property Office To improve the light efficiency and reduce the amount of the quantum dots used thereby, and to improve the durability of the quantum dots by excellent heat radiation, moisture and oxygen blocking. In addition, the nanoporous structure proposed in the above-referenced patent is linear in nanochannel, and its effective refractive index is the same from the beginning to the end of the nanochannel. Therefore, the durability of the impregnated or sealed quantum dots is excellent, but the optical properties thereof need to be improved.

Particularly, it is very important to control the wavelength and direction of emitted light in the application of the optical device. To increase the light efficiency and performance, a dual brightness enhancement film (DBEF) or a dichroic filter / reflector ) Have been used. However, they are very expensive because of multilayer coating or lamination of materials having different refractive indexes with a very precise thickness, and there is a problem that complex individual processes are required to apply these parts to optical devices.

In order to solve the problems of the prior art as described above, it is an object of the present invention to control the traveling direction of light by modulating the effective refractive index according to the modulation of the nanoporous structure, and to increase the light efficiency of the nanoporous structure.

Another object of the present invention is to increase the optical efficiency of a transmission type or reflection type wavelength selective nanoporous structure by increasing the selectivity of the wavelength by modulating the effective refractive index according to the modulation of the nanoporous structure.

It is another object of the present invention to provide an inexpensive transmission type or reflection type wavelength selective nanoporous structure.

In addition, the present invention aims at minimizing the influence of oxygen and moisture interception and efficient heat dissipation, thereby increasing lifetime and durability of the quantum dot.

The present invention also aims at minimizing loss of energy and improving operation reliability.

It is another object of the present invention to provide an optical device such as an ultraviolet ray or blue light excitation light emission backlight unit using a nanoporous structure.

It is another object of the present invention to provide a heat dissipating effect and to prevent a decrease in durability due to heat damage.

Other objects of the present invention will become readily apparent from the following description of the embodiments.

In order to achieve the above object, according to one aspect of the present invention, there is provided a nanoporous material comprising a plurality of pores; A nanophosphor provided in the pore and sealed; And a reflective portion formed on the inner surface of the pore to modulate an effective refractive index to allow selective reflection of the nano-fluorescent material with respect to an optical wavelength of the nanoporous structure.

The nanoporous material may be formed by controlling the size and period of the voltage or current waveform in the method, and the pores may be formed by electrochemical etching or anodic oxidation.

The nanoporous material can be obtained by locally etching or anodizing after masking to pattern the substrate.

The voltage or current waveform may be any one of a triangular wave, a square wave, a trapezoid wave, and a sinusoidal wave, or a composite file thereof.

The nanophosphor may be a polymer-encapsulated QD encapsulated with a polymer.

In each of the pores, only one kind of the red light emitting quantum dot, the green light emitting quantum dot, and the blue light emitting quantum dot may be injected as the nanophosphor, or a combination thereof may be injected.

The reflective portion may be formed to extend from the inner surface of the pore to a portion thereof, or may extend from the inner surface of the pore to the entire surface.

The reflective portion may be formed as a plurality of regions on the inner surface of the pores to reflect each of a plurality of light wavelength ranges of red light, green light, and blue light.

The reflective portion may be formed as a single region that reflects a plurality of light wavelength bands among red light, green light, and blue light on the inner surface of the pores.

The wavelength-selective nanoporous structure may be for transmitting light.

The nanoporous material can be made into a transparent structure by converting the metal of the substrate into a transparent metal oxide or by etching the valve metal remaining on the back by proceeding the anodic oxidation process to the substrate.

The wavelength-selective nanoporous structure may be a semi-use of light.

The nanoporous material may be partially etched or anodized to leave a valve metal on the back surface to form a reflector.

The nano-fluorescent material may further include heat-radiating particles formed on the pores and made of a light-transmitting material for heat radiation. The heat dissipating particles may include a part or all of AlN, c-BN, h-BN, MgO and Si ₃ N ₄ .

And a first heat discharger disposed on one or both surfaces of the nano-porous body and made of a light-transmitting material for heat dissipation. The first heat discharger may include a part or all of AlN, c-BN, h-BN, MgO and Si ₃ N ₄ .

And a second heat discharger disposed on a side of the nanoporous material where light is reflected, the second heat radiator being made of a material for heat dissipation on the back surface. The second heat discharger may include a part or all of graphene, graphite, SiC, AlN, c-BN, h-BN, MgO and Si ₃ N ₄ .

The wavelength selective nanoporous structure may be a color conversion member that performs color conversion by illumination or light from a light source of a backlight unit.

According to the wavelength-selective nanoporous structure according to the present invention, the wavelength selective nanoporous structure can be easily manufactured to broaden the application range of the optical device, increase the optical efficiency of the optical device, and prevent oxygen, moisture, The lifetime and durability of the quantum dots can be increased, energy loss can be minimized, operation reliability can be increased, manufacturing cost can be reduced, heat dissipation is excellent, and heat It is possible to prevent deterioration of durability due to damage.

1 is a schematic view showing a wavelength-selective nanoporous structure according to an example of the present invention.
2 is a schematic view showing a wavelength-selective nanoporous structure according to another example of the present invention.
3 is a cross-sectional view showing a wavelength-selective nanoporous structure according to the first embodiment of the present invention.
4 is a partial cross-sectional view for explaining the operation of the wavelength selective nanoporous structure according to the first embodiment of the present invention.
5 is a partial cross-sectional view showing a wavelength-selective nanoporous structure according to a second embodiment of the present invention.
6 is a partial cross-sectional view showing a wavelength-selective nanoporous structure according to the third embodiment of the present invention.
7 is a partial cross-sectional view showing a wavelength-selective nanoporous structure according to a fourth embodiment of the present invention.
8 is a partial cross-sectional view showing a wavelength-selective nanoporous structure according to the fifth embodiment of the present invention.
9 is a cross-sectional view showing a wavelength-selective nanoporous structure according to a sixth embodiment of the present invention.
10 is a cross-sectional view showing a wavelength-selective nanoporous structure according to a seventh embodiment of the present invention.
11 is a cross-sectional view showing a wavelength-selective nanoporous structure according to an eighth embodiment of the present invention.

The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated and described in detail in the drawings. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but is to be understood to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention, And the scope of the present invention is not limited to the following examples.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings, wherein like or corresponding elements are denoted by the same reference numerals, and redundant explanations thereof will be omitted.

FIG. 1 is a schematic view showing a wavelength-selective nanoporous structure according to an example of the present invention, and FIG. 3 is a cross-sectional view illustrating a wavelength-selective nanoporous structure according to a first embodiment of the present invention.

1 and 3, a wavelength selective nanoporous structure 100 according to an exemplary embodiment of the present invention is excited by a light source 10 to have luminescent properties, and the light of the light source 10 And shows a transmissive type. The wavelength selective nanoporous structure 100 according to an embodiment of the present invention includes a nanoporous material 110 having a plurality of pores 120 formed thereon, nanophosphors 141, 142 and 143 provided in the pores 120 to be sealed, 120 for modulating an effective index of refraction on the inner surface of the nano-sized fluorescent material 141, 142, 143 to selectively reflect light with respect to an optical wavelength of the nano-fluorescent material 141, 142, 143.

In one embodiment of the present invention, the wavelength-selective nanoporous structure 100 is used for transmitting light. For example, the nanoporous material 110 is subjected to an anodic oxidation process to the substrate to convert the metal of the substrate into a transparent metal oxide Or by etching the valve metal remaining on the backside. The wavelength selective nanoporous structure 100 may be a transmissive type color conversion member that performs color conversion by light or light from a light source of a backlight unit by being excited by a separate light source 10. In this embodiment, the wavelength-selective nanoporous structure 100 can be applied as an edge-type or direct-type light source to a light guide plate. When the light source is a transmissive light source for a light guide plate impregnated with nano-sized fluorescent material (141, 142, 143) in the structure of nano-pores 120, a separate light source 10, for example, ultraviolet light excites green, red, and blue nano fluorescent substances 141, 142, , Red and blue fluorescence are induced, and the fluorescent light is mixed to exhibit white light, and this white light proceeds in the direction of the light guide plate. The nanoporous material 110 is formed by performing a continuous process in the same manner as the formation of the nanoporous structure by the conventional anodic oxidation process except that only the waveform of the voltage or the current is changed for the manufacture thereof, It is possible to improve the function and economical efficiency.

Referring to FIG. 2, the wavelength selective nanoporous structure 100A according to another embodiment of the present invention is a reflection type that reflects light so excited that the light is excited by the light source 10. FIG. The wavelength selective nanoporous structure 100A according to another example of the present invention includes a nanoporous material 110 in which a plurality of pores 120 are formed as in the wavelength selective nanoporous structure 100 according to an exemplary embodiment of the present invention, A reflective part 130 formed on the inner surface of the pores 120 for modifying an effective refractive index to selectively reflect light with respect to an optical wavelength of the nano- The reflector 160 may be provided on one side of the nanoporous material 110 of the wavelength selective nanoporous structure 100 according to an exemplary embodiment of the present invention. .

In another embodiment of the present invention, the wavelength-selective nanoporous structure 100A is a semi-use of light, for example, the nanoporous material 110 is partially subjected to an etching or anodizing process on the substrate, leaving a valve metal on the back surface, 160). The wavelength selective nanoporous structure 100A is excited by a separate light source 10 to form a color conversion member that is a reflection type and performs color conversion by light from a light source of a backlight unit or illumination. In this embodiment, the valve metal such as Al, Ti, Zr, Hf, Nb, Mo, W and Ta has a very high reflectance of visible light and a very high thermal conductivity, Structure reflective type backlight unit. Accordingly, when only a part of the metal surface is anodized and the back metal is left on the anodized nanoporous material and the nano-fluorescent material is used as a reflective light source, almost all the light is reflected by the reflection effect of the reflector 160 corresponding to the back metal The light efficiency of the illumination or the backlight unit can be greatly increased and the heat radiation effect due to the high thermal conductivity of the reflector 160 corresponding to the back metal portion can be greatly improved. Also, when the visible light region absorbance of the metal itself is significant, and multiple reflection of light occurs, including total reflection, in the reflector 160 of the backlight unit, the attenuation of light due to the absorption of metals such as aluminum (Al) . To solve this problem, a nano-porous structure having a wavelength-selective stop band of blue and red regions having the highest absorbance is formed, or a broadband stop band including blue, green and red regions is formed , It is possible to realize a highly efficient reflective structure without light attenuation due to light absorption of aluminum.

The reflective type wavelength selective nanoporous structure 100A according to another embodiment of the present invention is a structure in which the transmissive type wavelength selective nanoporous structure 100 according to one embodiment of the present invention has the reflector 160 The description of each of the structures, for example, the nano-porous body 110, the pores 120, the reflective portion 130, and the nano-phosphors, and the modified embodiments thereof will be described in detail later The corresponding structures in the wavelength selective nanoporous structure 100 according to an embodiment of the present invention will be described instead.

FIG. 3 is a cross-sectional view showing a wavelength-selective nanoporous structure according to a first embodiment of the present invention, and FIG. 4 is a partial cross-sectional view for explaining the operation of the wavelength-selective nanoporous structure according to the first embodiment of the present invention.

3 and 4, the wavelength selective nanoporous structure 100 may include a nanoporous material 110, nanophosphors 141, 142, and 143, and a reflective portion 130, as described above.

The nanoporous material 110 may be formed by electrochemical etching or anodic oxidation, and may be obtained by masking the substrate for patterning and then locally etching or anodizing the substrate. At this time, the reflector 130 may be formed by adjusting the magnitude and period of the voltage or current waveform in the above method. Here, the voltage or current waveform may be any one of a triangle wave, a square wave, a trapezoid wave, and a sine wave, or a composite file thereof. The reflector 130 may be formed on the inner surface of the pores 120, for example, on the side opposite to the inlet of the pores 120. The reflector 130 may have protrusions or grooves As shown in FIG.

For example, DBR (Distributed Bragg Reflectors) may be used to realize a wavelength selective reflector by forming the reflective portion 130. This is because dielectrics having different refractive indexes (nH, nL) and thicknesses (dH, dL) are alternately stacked to form a bandgap at a specific wavelength and completely reflect the light corresponding to the bandgap. At this time, the optical wavelength is given by λ ₀ = 2 (nHdH + nLdL). The pores 120 can be formed by a very simple electrochemical etching or anodic oxidation method, unlike the deposition method generally used in the production thereof. The electrochemical nanoporous material 110 may be formed by a pulse etching method or a pulsed anodic oxidation method. If etching or anodic oxidation is performed under high voltage or high current conditions, the pore size and growth rate in the nanoporous material 110 will increase. Therefore, when voltage or current pulses of different size and time periodically are applied periodically, the size and period of the nano-sized pores 120 are changed, so that the effective refractive index is modulated and an easy DBR is created. More sophisticated optical constants, such as the position of the stop band, the half width and the reflectivity, can be obtained through a pore widening method of the manufactured nanoporous material 110. However, in the DBR structure, a harmonic band is generated at a wavelength position of ? ₀ / m (m> 1), and the second and third stop bands of undesired high wavelength band other than the main stop band And in addition, an undesired sidelobe may be produced on both sides of each stop band.

In order to solve the disadvantages of the DBR, for example, a rugate filter can be applied to the nanoporous material 110. For this purpose, during the fabrication of the nanoporous material 110, a sine wave voltage or current is applied instead of the pulse type in the etching or the anodic oxidation process, and the voltage or current intensity is gradually increased or decreased, It is possible to smoothly and regularly modulate the pore 120 profile (that is, the refractive index) to form the reflecting portion 130. The rugged filter is formed with a single stop band without second and third stop bands due to harmonics, and the band width is narrower (pi / 4). The refractive indices according to their positions can be expressed as n (x) = na + 1 / 2np sin (2πx / T + φ ₀ ) where na, np, T and φ ₀ are the average refractive index, the period of the sine wave and the phase (radian) of the substrate. The wavelength of the stop band is represented by the equation of? ₀ = 2T.

In order to form the nano porous body 110, the pores 120, and the reflective portion 130, for example, a pixel pattern may be patterned with a masking agent and then anodized to form a pixel. At the beginning of the anodic oxidation process, a linear channel is formed by a constant voltage or a constant current, and then a pulse or sine wave voltage or current is applied according to the above method to reach the bottom, (That is, the refractive index), thereby forming the reflective portion 130. Thus, each pixel has a characteristic of transmitting green light and red light, for example, while transmitting blue light. At this time, the profiles of the pores 120 and the reflection part 130 are set such that the refractive index of the anodic alumina (n = 1.78), the refractive indices of the nano-phosphors 141, 142, 143 and the polymer 150 to be filled in the pores 120, , The half width, and the reflectance. Then, each pixel is filled with a composite of the nano-phosphors (141, 142, 143) or the nano-phosphors (141, 142, 143) and the polymer 150 to be protected or sealed.

For example, a rugate filter having two reflection wavelengths as well as a single reflection wavelength can be applied to an optical device composed of RGB primary colors. The blue light is passed through, and the simultaneous selective reflection of the green light and the red light can simplify the structure of the optical element and greatly improve the performance and efficiency of the optical element. As a method of realizing this, a method of forming two structures successively and a method of etching or anodizing by forming a profile of a current or a voltage by synthesizing a desired frequency of two wavelengths are possible. At this time, when the apodization is performed, the side lobe of the stop band is also removed.

The production of a lugging filter having a stop band of a wide wavelength shown as an example in the present invention can be obtained by continuously changing the period of the lugging. Base period of the gate is the maximum value (Tmax) and Ti = Tmax according to the minimum value (Tmin) - (Tmax - Tmin ) was given a strain according to (i - - 1 / N 1 ) α can be obtained. In this equation, N and α are parameters that control the total number of loop gating cycles and the distribution of cycles, respectively.

The nano-phosphors 141, 142 and 143 may be polymer-encapsulated QD encapsulated with a polymer. Green light emitting quantum dots 142, and blue light emitting quantum dots 143 corresponding to R, G, and B, respectively, as the nano fluorescent substances 141, 142, and 143 in the pores 120, A combination of a red light emitting quantum dot 141, a green light emitting quantum dot 142 and a blue light emitting quantum dot 143 may be injected. In addition, only the nano-phosphors 141, 142 and 143 are injected into the pores 120 and sealed, or the polymer 150 is mixed with the nano-phosphors 141, 142 and 143 in the pores 120 as shown in this embodiment. In the case of the light source 10 (shown in Fig. 1) providing ultraviolet rays as in this embodiment, the red light emitting quantum dot 141 of the corresponding color, the green light emitting The quantum dot 142 and the blue light emitting quantum dot 143 can be injected as a single kind.

As the nano-phosphors 141, 142, 143, quantum dots can be synthesized by, for example, a chemical wet process. The chemical wet method is a method of growing particles by adding a precursor material to an organic solvent, and a method of synthesizing a quantum dot by a chemical wet method is a well known technique. The quantum dot may be a II-VI compound such as CdSe, CdTe, CdS, ZnSe, ZnTe, ZnS, HgTe or HgS. The quantum dot may have a core-shell structure. Wherein the core may comprise any one material selected from the group consisting of CdSe, CdTe, CdS, ZnSe, ZnTe, ZnS, HgTe and HgS, and the shell may comprise CdSe, CdTe, CdS, ZnSe, ZnTe, ZnS, HgTe and HgS And the like. III-V compounds such as InP are also possible. Nano-sized phosphors 141, 142, and 143 are not limited to the above-described examples, and nano-sized phosphors having various structures and components can be applied.

5, the reflector 230 is formed on the inner side of the pores 220 of the nanoporous material 210, for example, on the entrance side of the pores 220. [ The position of the reflective portion 230 in the pores 220 may vary depending on the depth, diameter or width of the pores 220, the material of the nano-porous body 210, the position of the light source 10 (shown in FIG. 1) And the excitation light such as ultraviolet rays or blue light is circulated in the pores 220 by reflection to increase the excitation frequency with respect to the nano-phosphors to increase the luminous efficiency. The circulation utilization of the excitation light corresponds to the same application in all the embodiments of the present invention. 6, the reflection portion 330 may be formed to extend from the inside of the pores 320 of the nano-porous body 310 to the entire surface thereof.

Referring to FIG. 7, the reflection parts 431 and 432 may be formed on the inner surfaces of the pores 420 of the nano-porous body 410 to reflect a plurality of light wavelength ranges of red light, green light, and blue light, respectively. At this time, a plurality of quantum dots selected from a red light emitting quantum dot 441, a green light emitting quantum dot 442 and a blue light emitting quantum dot may be mixed and injected into the pores 420. 8, the reflection portion 530 may be formed as a single region that reflects a plurality of light wavelength bands of red light, green light, and blue light on the inner surface of the pores 520 of the nano-porous body 510. At this time, a plurality of kinds of quantum dots selected from red light emitting quantum dots 541, green light emitting quantum dots 542 and blue light emitting quantum dots may be mixed and injected into the pores 520.

9, the wavelength selective nanoporous structure 600 according to another embodiment of the present invention includes a nanoporous material 610 having pores 620 corresponding to the red pixel region R and the green pixel region G, The red light emitting quantum dot 641 and the green light emitting quantum dot 642 may be respectively injected into the hole 620 and the reflective portion 630 may be formed on the inner side of the hole 620. However, The phosphor layer 620 may be formed in a blank state without a reflective portion or a nanophosphor so as to use the blue light from the light source 10 (shown in Fig. 1).

10, the wavelength selective nanoporous structure 1100 according to the seventh embodiment of the present invention is of a transmissive type and includes a nanoporous material 1110 having a plurality of pores 1120 formed thereon, The nano-phosphors 1141, 1142 and 1143 are sealed to modulate the effective refractive index on the inner surface of the pores 1120, and the nano-phosphors 1141, 1142, and 1143 are selectively refracted The nano-sized phosphors 1141, 1142, and 1143 may be provided in the pores 1120. In addition, the nano-sized phosphors 1141, And heat radiation particles 1150 made of a light-transmitting material for heat radiation. The heat dissipating particles 1150 may have a diameter smaller than the inner diameter of the pores 1120, for example, 300 nm, and may be sealed in the pores 1120 together with the polymer, not limited to a plate or a sphere. In addition, heat radiation particle 1150 is, for example AlN, c-BN, h-BN, MgO, and Si ₃ N ₄ may comprise some or all selected from, but this is not necessarily limited thereto as illustrated.

The wavelength selective nanoporous structure 1100 according to the seventh embodiment of the present invention includes first heat dissipators 1170 and 1180 formed on one or both surfaces of the nanoporous material 1110 and made of a light transmitting material for dissipating heat . Here, the first heat discharging bodies 1170 and 1180 may include a part or all of AlN, c-BN, h-BN, MgO and Si ₃ N ₄ , but the present invention is not limited thereto. In this embodiment, the first heat discharging bodies 1170 and 1180 are formed on both surfaces of the nano porous body 1110. However, the present invention is not limited to this, and may be formed only on the light incident side surface of the nano porous body 1110, . Also, the first heat discharging bodies 1170 and 1180 are not limited in shape, but may be advantageous in gas barrier effect when they are formed in a plate-like shape.

11, the wavelength-selective nanoporous structure 1200 according to the eighth embodiment of the present invention is of a reflective type, and includes a nanoporous material 1210 having a plurality of pores 1220 formed thereon, Nano-sized phosphors 1241, 1242 and 1243 are provided to be sealed and modulated with an effective refractive index on the inner surface of the pores 1220 to selectively reflect light of wavelengths of the nanophosphors 1241, 1242 and 1243 Nano-sized phosphors 1241, 1242, and 1243 may be included in the pores 1220. In addition, the nano-sized phosphors 1241, 1242, and 1243 may be replaced with nano- And may further include heat dissipation particles 1250 made of a light-transmitting material for heat dissipation. The heat dissipating particles 1250 may have a diameter smaller than the inner diameter of the pores 1220, for example, 300 nm, and may be sealed in the pores 1220 together with the polymer, not limited to the plate or the spherical shape. In addition, particle radiation (1250), for example AlN, c-BN, h-BN, MgO, and Si ₃ N ₄ may comprise some or all selected from, but this is not necessarily limited thereto as illustrated.

The wavelength-selective nanoporous structure 1200 according to the eighth embodiment of the present invention is provided on a side where light is reflected by the nanoporous material 1210, for example, on the exposed surface of the reflector 1260, And may further include a second heat discharger 1270. Wherein the second heat sink 1270 is graphene (graphene), graphite (graphite), SiC, AlN, c-BN, h-BN, MgO, and Si ₃ N ₄ may comprise some or all selected from the group consisting of, For example, it is not limited thereto but may be integrally formed. Alternatively, when the coating is formed by coating, it may be formed of particles and used with various coating materials.

The function of the wavelength selective nanoporous structure according to the present invention will now be described.

According to the present invention, a nanoporous phosphor is impregnated into the pores of a nanoporous structure to have a heat dissipation property, and a light emitting layer having a wavelength selective reflection function can be obtained in an outer environment including moisture and oxygen and a nanoporous structure blocked. The light efficiency of the light emitting diode can be remarkably improved.

In addition, when the effective refractive index of the nanoporous structure is modulated by periodically controlling the voltage or current during etching or anodization, a nanoporous structure having various optical characteristics can be easily manufactured. In particular, a wavelength selective reflection function So that its utility and application field can be significantly enlarged.

Nanoporous structures such as nanoporous alumina and nanoporous silicon exhibit various optical properties and can be used as nano-sized storage vessels to hold a variety of photoactive molecules or nanophosphorescent materials sensitive to the surrounding environment with oxygen and moisture, And can be isolated from the environment. Therefore, it is very suitable for manufacturing an optical element having excellent optical characteristics and durability. In addition, various nanoporous structures can be obtained by electrochemically etching or anodizing the valve metals such as silicon or aluminum, thereby changing the effective refractive index of the nanoporous structure to confine or induce light, Or selectively transmit or reflect. This makes it possible to fabricate various optical devices such as antireflection layer, omnidirectional mirror, microcavity, distributed Bragg reflector, waveguide, and rugate filter.

Although the present invention has been described with reference to the accompanying drawings, it is to be understood that various changes and modifications may be made without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

110, 210, 310, 410, 510, 610, 1110, 1210:
120,220,320,420,520,620,1120,1220:
130, 230, 330, 431, 432, 530, 630, 1130,
141, 142, 143, 441, 442, 443, 641, 642, 1141, 1142, 1143, 1241, 1242,
150: polymer
160, 1260: reflector
1150, 1250:
1160, 1170:
1270: second heat radiator
R: Red pixel area
G: green pixel area
B: blue pixel region

Claims (21)

A nano porous body having a plurality of pores formed therein;
A nanophosphor provided in the pore and sealed; And
A reflective portion formed on the inner surface of the pores to modulate an effective refractive index to cause selective reflection of the nano-sized phosphor with respect to an optical wavelength;
/ RTI > nanoporous structure. The method according to claim 1,
The nano-
Wherein the pores are formed by an electrochemical etching or an anodic oxidation method,
The reflector includes:
Wherein the wavelength-selective nanoporous structure is formed by controlling the magnitude and period of a voltage or a current waveform in the method. The method of claim 2,
The nano-
A wavelength-selective nanoporous structure obtained by masking to pattern a substrate and then locally etching or anodizing the substrate. The method of claim 2,
The voltage or current waveform may be,
A triangular wave, a square wave, a trapezoidal wave, and a sinusoidal wave, or a composite fine thereof, a wavelength-selective nanoporous structure. The method according to claim 1,
The nano-
A polymer-encapsulated QD, a wavelength-selective nanoporous structure. The method according to claim 1,
In each of the pores,
Wherein the nanoporous phosphor is injected only with one of a red light emitting quantum dot, a green light emitting quantum dot and a blue light emitting quantum dot, or a combination thereof is injected. The method according to claim 1,
The reflector includes:
And is formed over a part of the inside of the pores. The method according to claim 1,
The reflector includes:
And is formed all over the inner side of the pores. The method according to claim 1,
The reflector includes:
And a plurality of regions for reflecting a plurality of light wavelength bands in red light, green light, and blue light, respectively, on inner surfaces of the pores. The method according to claim 1,
The reflector includes:
Wherein the pores are formed as a single region that reflects a plurality of light wavelength bands in red light, green light, and blue light on the inner surface of the pores. The method according to claim 1,
The wavelength-selective nanoporous structure may be formed by,
A wavelength-selective nanoporous structure for transmission of light. The method of claim 11,
The nano-
Wherein the substrate is made of a transparent structure by conducting an anodic oxidation process on the substrate to convert all of the metal of the substrate into a transparent metal oxide or etching the valve metal remaining on the back surface. The method according to claim 1,
The wavelength-selective nanoporous structure may be formed by,
A wavelength selective nanoporous structure for reflection of light. 14. The method of claim 13,
The nano-
Wherein the substrate is partially subjected to an etching or anodizing process to leave a valve metal on the back surface to form a reflector. The method according to claim 1,
Further comprising heat radiation particles provided in the pores together with the nanophosphor and made of a light transmitting material for heat radiation. 16. The method of claim 15,
The heat-
And a part or all selected from AlN, c-BN, h-BN, MgO and Si ₃ N ₄ . The method of claim 11,
Wherein the nanoporous structure further comprises a first heat discharger provided on one or both surfaces of the nanoporous material and made of a light transmitting material for heat radiation. 18. The method of claim 17,
The first heat-
And a part or all selected from AlN, c-BN, h-BN, MgO and Si ₃ N ₄ . 14. The method of claim 13,
Wherein the nanoporous structure further comprises a second heat discharger provided on a side surface of the nanoporous material on which light is reflected and made of a material for heat radiation on the back surface. The method of claim 19,
The second heat-
Selected from the group consisting of graphene, graphite, SiC, AlN, c-BN, h-BN, MgO and Si ₃ N ₄ . The method according to any one of claims 1 to 20,
The wavelength-selective nanoporous structure may be formed by,
And a color conversion member which performs color conversion by light from a light source of the illumination or backlight unit.

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