KR102087358B1 - Low reflection polarizer - Google Patents

Abstract

The present application is directed to low reflection polarizers for low reflection and selective wavelength absorption and transmission.

Description

LOW REFLECTION POLARIZER}

The present application relates to low reflection polarizers for low reflection and selective wavelength absorption and high transmission.

The polarizer is a material that transmits or blocks light depending on the polarization state of the light (in the direction of electric field). Most of the light polarizers are used in small mobile LCD displays, LCD computer monitors, LCD TVs, automotive touch panels, and AMOLED displays. It is an essential material for display panels. In order to reduce the size and thickness of display materials used with miniaturization of high-tech equipment, various researches are underway, and continuous research and development has been made in optimizing optical characteristics such as contrast ratio and sharpness.

The polarizer technology up to now has fundamentally included the problem of reflection of blocked polarized light because it focused on the property of transmitting or blocking according to the polarization direction of light with respect to high transmittance. This implies the presence of internal scattering and external light reflections in display device applications, leading to problems of lowering contrast, sharpness and efficiency. In addition, the color filter used in the conventional display device is composed of an organic material, which is a material independent of the polarizer, and takes a large part in the display device configuration.

Currently developed highly transparent polarizers utilize wire grid structural materials, which transmit polarized light perpendicular to the wire grid direction and block parallel polarized light. In this case, since the blocked polarized light is mostly reflected, it causes reflection of external light on the display, and decreases contrast ratio and sharpness. In addition, although studies on the need for an additional low reflection layer have been conducted to achieve high transmission of orthogonal polarization, approaches to the reflection problem of blocked polarized light (parallel polarized light) are insufficient.

In addition, in order to configure the existing display device, an additional color filter material is necessary together with the polarizer, and since the materials are formed in layers independently, there is a limit in miniaturization and thinning of the display device.

United States Patent Application Publication US 20150077851 A1

The present application relates to low reflection polarizers for low reflection and selective wavelength absorption and high transmission.

However, the problem to be solved by the present application is not limited to the above-mentioned problem, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

According to a first aspect of the present disclosure, a low reflection polarizer including a polarization layer, wherein the polarization layer includes a plurality of unit cells including one wire and a first dielectric surrounding the plurality of unit cells, and the unit to volume of the unit cell. The plurality of unit cells are arranged so that the volume ratio of the wires included in the cell is gradually increased or decreased in the direction in which light is incident.

According to the embodiments of the present invention, by removing a reflected light by the polarizer irrespective of the polarization direction through a plurality of wires arranged inside the polarizer, there is an effect of solving the problems of scattering and external light reflection of the display element.

According to the embodiments of the present invention, by controlling the resonant wavelength of the wire included in the polarizer to absorb or transmit the wavelength of light that is selectively incident, there is an effect that can create a display element that does not require an additional color filter, This can help to thin the display.

According to the embodiments of the present disclosure, since an inorganic-based polarizer may be manufactured, stability to an environment such as UV, moisture, and high temperature may be ensured.

1 is a perspective view of a low reflection polarizer according to an embodiment of the present disclosure.
2 is a cross-sectional view of a low reflection polarizer according to an embodiment of the present application.
3 is a cross-sectional view of a plurality of unit cells in a low reflection polarizer according to one embodiment of the present application: (a) a unit cell comprising a metal wire, (b) a unit cell comprising a metal core-dielectric shell wire and (c) a unit cell comprising a dielectric core-metal shell wire.
4 is a graph showing the reflectance of the vertically polarized light and the transmittance of the orthogonal polarized light in the low reflection polarizer according to the exemplary embodiment of the present application.
5 is a view showing the arrangement of the first wire array and the second wire array in the low reflection polarizer according to an embodiment of the present application: (a) vertical sequential array, (b) horizontal sequential array.
FIG. 6A is a graph illustrating selective absorption wavelength control through alteration of a first dielectric in a single metal nanowire in a low reflection polarizer according to an embodiment of the present disclosure.
FIG. 6B is a graph showing selective absorption wavelength control according to the type of metal core in the metal core-dielectric shell wire in the low reflection polarizer according to the exemplary embodiment of the present application.
FIG. 6C is a graph showing selective absorption wavelength control according to dielectric shell change in a metal core-dielectric shell wire in a low reflection polarizer according to an embodiment of the present disclosure.
FIG. 6D is a graph showing selective absorption wavelength control according to a change in metal core cross-sectional area in a metal core-dielectric shell wire in a low reflection polarizer according to an embodiment of the present disclosure.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present disclosure. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention. In the drawings, parts irrelevant to the description are omitted for simplicity of explanation, and like reference numerals designate like parts throughout the specification.

Throughout this specification, when a part is said to be "connected" to another part, it includes not only "directly connected" but also "electrically connected" with another element in between. do.

Throughout this specification, when a member is located “on” another member, this includes not only when one member is in contact with another member but also when another member exists between the two members.

Throughout this specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding the other components unless specifically stated otherwise. As used throughout this specification, the terms “about”, “substantially”, and the like, are used at, or in close proximity to, numerical values when manufacturing and material tolerances inherent in the meanings indicated are provided, and an understanding of the present application may occur. Accurate or absolute figures are used to assist in the prevention of unfair use by unscrupulous infringers. As used throughout this specification, the term “step of” or “step of” does not mean “step for”.

Throughout this specification, the term “combination (s) thereof” included in the expression of a makushi form refers to one or more mixtures or combinations selected from the group consisting of the components described in the expression of makushi form, It means to include one or more selected from the group consisting of the above components.

Throughout this specification, the description of “A and / or B” means “A or B, or A and B”.

Hereinafter, with reference to the accompanying drawings will be described in detail the embodiments and embodiments of the present application. However, the present disclosure may not be limited to these embodiments, examples, and drawings.

A first aspect of the present application is a low reflection polarizer comprising a polarizing layer, wherein the polarizing layer comprises a plurality of unit cells including a wire and a first dielectric surrounding the unit, wherein the unit relative to the volume of the unit cell The plurality of unit cells are arranged such that the volume ratio of the wires included in the cell is gradually increased or decreased in the direction in which light is incident.

In one embodiment of the present application, the first dielectric may be formed of a synthetic material such as a porous dielectric material having a low effective permittivity, as well as a dielectric formed of a single material, but may not be limited thereto. For example, the first dielectric may be a porous dielectric material (such as nanoporous silicon), silicon dioxide (SiO ₂ ), magnesium fluoride (MgF ₂ ), sodium fluoride (NaF), silicon (Si), or Teflon (Teflon). Polymethyl Silsesquioxane (PMSSQ), Polystyrene-Poly Ethylene Glycol (PS-PEG), and combinations thereof, but may include a material selected from the group consisting of This may not be limited. In one embodiment of the present application, the dielectric constant of the wire may be greater than the dielectric constant of the first dielectric.

1 and 2, the unit cells including the wire and the first dielectric are arranged in parallel with each other, and the volume ratio of the wire to the volume of the unit cell gradually increases and decreases along the direction in which light is incident. The plurality of unit cells may be arranged, but is not limited thereto.

According to the exemplary embodiment of the present application, due to the characteristic that the volume ratio of the wire included in the unit cell is gradually changed from the volume of the unit cell, it is possible to control the reflection phase and / or intensity of the incident light, and reflect the light By using the interference phenomenon, irrespective of the polarization direction, destructive interference may occur in the reflected light to provide an effect of achieving low reflection of the polarizer while maintaining polarization performance.

According to one embodiment of the present application, the polarizer controls the scattering cross-sectional area of the light by a plurality of wires by controlling the volume ratio of the wires included in the unit cell to the volume of the unit cell, by using a plurality of layers of wire The principle of increasing the absorption cross-sectional area of the polarizer itself can provide the effect of achieving a low reflection of the polarizer.

In one embodiment of the present application, the wire may include, but is not limited to, a metal wire, a metal core-dielectric shell wire, or a dielectric core-metal shell wire.

Referring to FIG. 3, the wire may be a metal wire (FIG. 3A), a metal core-dielectric shell wire (FIG. 3B), or a dielectric core-metal shell wire (FIG. 3C). May be, but is not limited thereto.

In one embodiment of the present application, the volume ratio of the wire included in the unit cell to the volume of the unit cell may be 0.001 to 0.8, for example, the volume ratio is 0.001 to 0.8, 0.005 to 0.8, or 0.01 To 0.8, but is not limited thereto.

In one embodiment of the present application, the volume ratio of the wire included in the unit cell to the volume of the unit cell may be controlled by the size of the cross-sectional area of the wire included in the unit cell, but is not limited thereto.

In one embodiment of the present application, the wire may be to reduce the light reflected from the polarizer, and to increase the transmission of orthogonal polarization irrespective of the polarization direction.

In one embodiment of the present application, the low reflection polarizer may be used in the visible, infrared or ultraviolet region, but is not limited thereto.

In one embodiment of the present application, the low reflection polarizer may be to absorb or transmit the wavelength of light that is selectively incident by controlling the resonant wavelength of the wire. This is to control the resonant wavelength of the wire, it may be using a plasmonic effect, but is not limited thereto.

In one embodiment of the present application, it may be to control a single resonant wavelength of light incident through the metal wire or the metal core-dielectric shell wire.

In one embodiment of the present application, it may be to control the multiple resonant wavelength of light incident through the dielectric core-metal shell wire.

According to the exemplary embodiment of the present disclosure, in the metal wire, the metal core-dielectric shell wire, or the dielectric core-metal shell wire, the material of the wire, the cross-sectional area of the wire, and the kind of the first dielectric may be adjusted. It is possible to control the resonant wavelength of the wire.

Referring to Figure 4, by controlling one or more of the material of the wire, the size of the cross-sectional area of the wire and the type of the first dielectric to control the reflection phase and / or intensity of the light, regardless of the polarization direction, the polarizer is low reflection The effect and the effect of increasing the transmission of orthogonally polarized light can be confirmed.

In one embodiment of the present application, the aspect ratio of the cross section of the metal wire included in each of the plurality of unit cells may be the same or different from each other.

In one embodiment of the present application, the aspect ratio of the cross section of the metal wire may be about 1 to about 10, but is not limited thereto.

In one embodiment of the present application, the "metal" may include one selected from the group consisting of metal compounds such as metals, alloys, oxides of metals, and combinations thereof, but is not limited thereto. As a specific non-limiting example, the plurality of wires may include a metal or an alloy having a relatively low light absorption in the visible light region, for example, gold, silver, aluminum, copper, nickel, platinum, chromium, palladium, iron , Brass, zinc, bronze, and combinations thereof may include, but may not be limited to.

 Specifically, the single resonance wavelength of the incident light may be controlled by adjusting the aspect ratio of the cross-sectional area of the metal wire or by changing the metal type and / or dielectric type of the metal core-dielectric shell wire. In addition, the dielectric core-metal shell wire can control multiple resonant wavelengths of incident light through the cross-sectional area and / or material change of the wire. As a result, the polarizer enables selective absorption and transmission of a desired wavelength, thereby enabling vivid colors without additional color filters, thereby providing low reflection polarization and selective wavelength absorption.

In one embodiment of the present application, the polarizer controls the resonance wavelength of the wire by adjusting at least one of the type of the first dielectric, the aspect ratio of the metal wire, the cross-sectional area of the metal wire and the type of metal of the metal wire. It may be.

In one embodiment of the present application, the type of the first dielectric, the type of metal of the metal core-dielectric shell wire, the type of dielectric of the metal core-dielectric shell wire, the cross-sectional area of the metal of the metal core-dielectric shell wire, and The resonant wavelength of the wire may be controlled by adjusting one or more of the cross-sectional areas of the dielectric of the metal core-dielectric shell wire.

According to one embodiment of the present application, the type of the first dielectric, the type of metal of the dielectric core-metal shell wire, the type of dielectric of the dielectric core-metal shell wire, the cross-sectional area of the metal of the dielectric core-metal shell wire And controlling the resonant wavelength of the wire by adjusting at least one of the cross-sectional areas of the dielectric of the dielectric core-metal shell wire.

In one embodiment of the present application, the plurality of unit cells may include a combination of wires having different resonance wavelengths from each other. Specifically, the first wire array and the second wire array includes a first wire array and a second wire array sequentially arranged in the vertical direction or horizontal direction with respect to the incident light, wherein each of the first wire array and the second wire array includes a plurality of unit cells The wire arrays may have different resonance wavelengths.

Referring to FIG. 5, a first wire array A and a second wire array B including a plurality of unit cells and having different resonance wavelengths are sequentially arranged in a vertical direction with respect to incident light (FIG. 5A). ) Or the wires may be arranged in a horizontal sequential order (Fig. 5 (b)).

In one embodiment of the present application, during RGB color implementation through the vertical sequential arrangement of the first wire array and the second wire array, green (G) is selectively passed through and red (R) through the horizontal sequential array ) And blue (B) may be selectively passed, but is not limited thereto.

In one embodiment of the present application, the spacing of the wires of the plurality of unit cells is adjusted according to the dielectric constant of the first dielectric, the wires may be arranged at intervals of about 1 nm to about 100 nm, but is not limited thereto. Does not.

In one embodiment of the present application, the wire may be a nano wire, but is not limited thereto.

In one embodiment of the present application, the aspect ratio of the plurality of wires may be in the range of about 2 or more, or about 2 to about 1000, but is not limited thereto. Specifically, the aspect ratio of the wire is about 2 to about 1,000, about 2 to about 500, about 2 to about 100, about 2 to about 50, about 10 to about 1,000, about 10 to about 500, about 10 to about 100, Or about 10 to about 50, but is not limited thereto.

Hereinafter, the embodiments of the present application will be described in detail. However, the present application may not be limited thereto.

[ Example ]

One. Low reflection Polarizer  Produce

1-1. Containing a plurality of unit cells Low reflection Polarizer  Produce

Metal wire comprising silver (Ag) as the material of a single metal, metal core-dielectric shell comprising a dielectric shell using a material having a refractive index of 2 or more, and a dielectric core using a material having a refractive index of 2 or more, metal A dielectric core-metal shell containing silver was prepared as the material of the shell, but a plurality of the wires were adjusted to have different cross-sectional areas. Thereafter, the plurality of manufactured single metal wires, the plurality of metal core-dielectric shell wires, and the plurality of dielectric core-metal shell wires are each independently arranged in parallel with each other in the first dielectric, and the size of the cross-sectional area is gradually increased. The polarizing layer was arranged such that the volume ratio of the one wire to the volume of the unit cell was gradually increased or decreased in the direction in which light was incident by increasing and decreasing the volume. The diameters of the plurality of wire cross sections were increased and decreased in the range of 6 nm to 20 nm at 2 nm intervals. The plurality of wires were made up of 15 layers in total, so that the total thickness was 1200 nm.

1-2. First wire  Array and 2nd wire  Containing array Low reflection Polarizer  Produce

Vertical sequential arrangement (a) or horizontal direction with respect to light incident on the first wire array A and the second wire array B, including the plurality of wires and having different resonance wavelengths. The low reflection polarizer was prepared by arranging them sequentially (FIG. 5 (b)).

2. Low reflection  Confirmation of function

Reflectance and transmittance according to the wavelength of TE polarized light and TM polarized light were investigated. As a result, as shown in FIG. 4, the low reflection characteristics of the transmissive polarized light (parallel polarized light) as well as the low reflection of the transmitted polarized light (orthogonal polarized light) for high transmission in the visible region can achieve low reflection characteristics of 4% or less. I could confirm that.

3. Confirmation of selective wavelength absorption

As shown in FIG. 5, green (G) is selectively passed during RGB color implementation through the vertical sequential arrangement (FIG. 5A) of the first wire array A and the second wire array B, and , Red (R) and blue (B) was selectively passed through the horizontal sequential array (Fig. (B)).

As shown in FIG. 6A, silver (Ag) was used as a material of a single metal wire having a radius of 10 nm as a single metal wire, and it was confirmed that the absorption wavelength of the polarizer could be selected by controlling a single vacuum wavelength by changing the first dielectric. It was. As the dielectric constant of the first dielectric is increased, the absorption wavelength is gradually increased. This confirmed that the absorption wavelength can be selectively controlled by changing the type of the first dielectric.

As shown in Figure 6b, the selective absorption wavelength according to the type of metal core in the metal core-dielectric shell wire was confirmed. The radius of the metal core was 10 nm, the shell radius was 30 nm, and the dielectric constant of the dielectric shell was set at 2.7, and the metals were silver and gold (Au). As a result, the polarizer containing silver as the metal core absorbed the maximum wavelength around 470 nm, and the polarizer containing gold as the metal core absorbed the maximum wavelength near 570 nm. Through this, it was confirmed that the absorption wavelength can be selectively controlled according to the type of the metal core.

As shown in Figure 6c, the selective absorption wavelength according to the change of the dielectric shell in the metal core-dielectric shell wire was confirmed. The radius of the metal core was set to 10 nm, the shell radius to 30 nm, and the type of the metal core was set to gold. As a result of confirming that the dielectric constant of the dielectric shell was changed to 1.5 or 2.7, the polarizer with the dielectric constant 1.5 absorbed the wavelength near 500 nm and the polarizer with the dielectric constant 2.7 absorbed the wavelength near 570 nm. This confirms that the selective absorption wavelength can be controlled by changing the dielectric constant of the dielectric shell.

As shown in FIG. 6D, the selective absorption wavelength was confirmed by changing the cross-sectional area of the metal core in the metal core-dielectric shell wire. The type of metal core was gold, the radius of the dielectric shell was set to 30 nm, the dielectric constant of the dielectric shell was set to 2.7, and the radius of the metal core was changed to 5 nm or 20 nm. As a result, the polarizer having a radius of 5 nm of the metal core absorbed the maximum wavelength around 580 nm, and the polarizer having a radius of 20 nm of the metallic core absorbed the maximum wavelength around 530 nm. This confirms that the selective absorption wavelength can be controlled by changing the cross-sectional area of the metal core.

The above description of the present application is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present application. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as distributed may be implemented in a combined form.

The scope of the present application is indicated by the following claims rather than the above detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present application.

Claims (23)

As a low reflection polarizer containing a polarizing layer,
The polarizing layer includes a plurality of unit cells including one wire and a first dielectric surrounding the wire,
Wherein the plurality of unit cells are arranged such that the volume ratio of the wire included in the unit cell to the volume of the unit cell gradually increases or decreases in the direction in which light is incident,
Low reflection polarizer.
The method of claim 1,
And the dielectric constant of the wire is greater than that of the first dielectric.
The method of claim 1,
Wherein the wire comprises a metal wire, a metal core-dielectric shell wire or a dielectric core-metal shell wire.
The method of claim 1,
The volume ratio of the wire included in the unit cell to the volume of the unit cell is 0.001 to 0.8, low reflection polarizer.
The method of claim 1,
The volume ratio of the wire included in the unit cell to the volume of the unit cell is 0.01 to 0.8, low reflection polarizer.
The method of claim 1,
The volume ratio of the wire included in the unit cell to the volume of the unit cell is controlled by the size of the cross-sectional area of the wire included in the unit cell, low reflection polarizer.
The method of claim 1,
Wherein said wire reduces light reflected from said polarizer and increases transmission of orthogonal polarization, regardless of polarization direction.
The method of claim 1,
Low reflection polarizer, which is used in the visible, infrared or ultraviolet region.
The method of claim 1,
A low reflection polarizer which absorbs or transmits the wavelength of light which is selectively incident by controlling the resonant wavelength of the wire.
The method of claim 3, wherein
Low reflection polarizer to control a single resonant wavelength of light incident through the metal wire or the metal core-dielectric shell wire.
The method of claim 3, wherein
Low reflection polarizer to control multiple resonant wavelengths of light incident through the dielectric core-metal shell wire.
The method of claim 9,
And controlling the resonant wavelength of the wire through a change in one or more of a type of the first dielectric, a cross-sectional area of the wire, and a material of the wire.
The method of claim 3, wherein
Low aspect polarizer, wherein the aspect ratio of the cross section of the metal wire included in each of the plurality of unit cells are the same or different from each other.
The method of claim 3, wherein
The aspect ratio of the cross section of the said metal wire of the said some unit cell is 1-10, The low reflection polarizer.
The method of claim 10,
And controlling at least one of a kind of the first dielectric, an aspect ratio of a cross section of the metal wire, a cross sectional area of the metal wire, and a kind of metal of the metal wire to control the resonant wavelength of the wire.
The method of claim 10,
The kind of the first dielectric, the kind of metal of the metal core-dielectric shell wire, the kind of dielectric of the metal core-dielectric shell wire, the cross-sectional area of the metal of the metal core-dielectric shell wire, and the dielectric of the metal core-dielectric shell wire And controlling the resonant wavelength of the wire by adjusting at least one of the cross-sectional areas of the low reflection polarizer.
The method of claim 11,
The kind of the first dielectric, the kind of metal of the dielectric core-metal shell wire, the kind of dielectric of the dielectric core-metal shell wire, the cross-sectional area of the metal of the dielectric core-metal shell wire, and the dielectric core-metal shell wire And controlling the resonant wavelength of the wire by adjusting one or more of the cross-sectional areas of the dielectric of the low reflection polarizer.
The method of claim 1,
Wherein the plurality of unit cells comprise a combination of wires having different resonant wavelengths from each other.
The method of claim 18,
A first wire array and a second wire array vertically sequential or horizontally sequential to incident light,
The first wire array and the second wire array each comprises a plurality of the unit cells, the wire array has a different resonant wavelength, low reflection polarizer.
The method of claim 19,
The green (G) is selectively passed during the RGB color implementation through the vertical sequential array, and the red (R) and blue (B) is selectively passed through the horizontal sequential array, low reflection polarizer.
The method of claim 1,
The spacing of the wires of the plurality of unit cells is adjusted according to the dielectric constant of the first dielectric,
Wherein the wires are arranged at intervals of 1 nm to 100 nm.
The method of claim 1,
The wire is a low reflection polarizer, which is a nano wire.
The method of claim 1,
The aspect ratio of the wire is low reflection polarizer, which is in the range of 2 to 1000.

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