Patent ID: 12228837

MODES OF THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the spirit and scope of the present invention is not limited to a part of the embodiments described, and may be implemented in various other forms, and within the spirit and scope of the present invention, one or more of the elements of the embodiments may be selectively combined and replaced.

In addition, unless expressly otherwise defined and described, the terms used in the embodiments of the present invention (including technical and scientific terms) may be construed the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, and the terms such as those defined in commonly used dictionaries may be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art.

In addition, the terms used in the embodiments of the present invention are for describing the embodiments and are not intended to limit the present invention. In this specification, the singular forms may also include the plural forms unless specifically stated in the phrase, and may include at least one of all combinations that may be combined in A, B, and C when described in “at least one (or more) of A (and), B, and C”.

Further, in describing the elements of the embodiments of the present invention, the terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the elements from other elements, and the terms are not limited to the essence, order, or order of the elements.

In addition, when an element is described as being “connected”, “coupled”, or “connected” to another element, it may include not only when the element is directly “connected” to, “coupled” to, or “connected” to other elements, but also when the element is “connected”, “coupled”, or “connected” by another element between the element and other elements.

Further, when described as being formed or disposed “on (over)” or “under (below)” of each element, the “on (over)” or “under (below)” may include not only when two elements are directly connected to each other, but also when one or more other elements are formed or disposed between two elements.

Furthermore, when expressed as “on (over)” or “under (below)”, it may include not only the upper direction but also the lower direction based on one element.

Hereinafter, an electrophoretic particle and a light route control member including the same according to an embodiment will be described with reference to drawings. The light route control member described below relates to a switchable light route control member that drives in various modes according to the movement of electrophoretic particles application of a voltage.

First, an electrophoretic particle according to an embodiment will be described with reference toFIGS.1and2.

Referring toFIGS.1, the electrophoretic particles may have a multi-layered structure. In detail, the electrophoretic particles10may be formed in a core-shell structure. That is, the electrophoretic particles may include a core part11and a shell part12disposed to surround the core part11.

The core part11may include a black material. In detail, the core part11may include a material that absorbs light. For example, the core part11may include at least one of carbon black, copper oxide, zinc oxide, aniline black, and activated carbon. In detail, the core part11may include carbon black.

Referring toFIG.2, a pattern may be formed on the surface of the core part11. In detail, a plurality of patterns for increasing the surface roughness of the core part11may be formed on the surface of the core part11. These patterns may be defined as at least one pattern of grooves and protrusions formed on the surface of the core part11. That is, the surface of the core part11may not be formed smoothly, but may be formed to have a constant roughness due to grooves and/or protrusions. That is, a plurality of grooves, a plurality of protrusions, or a plurality of grooves and a plurality of protrusions may be formed on the surface of the core part11.

The grooves and/or protrusions formed on the surface of the core part11may be formed on the surface of the core part11at irregular intervals, non-uniform sizes and non-uniform shapes. That is, the surface of the core part11may be formed in an uneven shape or a concave-convex pattern shape by the grooves and/or protrusions.

The grooves and/or protrusions formed on the surface of the core part11may be formed by various methods. For example, a spherical surface shape may be formed on the surface of the core part11by a chemical etching method using an alkali solution or the like.

In addition, when manufacturing the core part11, a plurality of nanoparticles, for example, a plurality of nano-sized carbon black particles is aggregated to form the core part11. Thereby the surface shape of the core part11may be formed to have an overall uneven shape.

The grooves and/or protrusions formed on the surface of the core part11may increase the surface roughness of the core part11. In addition, the specific surface area of the core part11may be increased by the grooves and/or protrusions formed on the surface of the core part11. That is, the specific surface area of the core part11may be increased while maintaining the particle diameter of the core part11. That is, compared to the core part having the same particle diameter, the core part11may have a larger specific surface area due to the pattern.

For example, the specific surface area of the core part11may be about 200 m2/g to 650 m2/g. In detail, the particle diameter of the core part11is 50 nm to 800 nm, and in this case, the specific surface area of the core part11may be about 200 m2/g to 650 m2/g. Preferably, the particle diameter of the core part11may be 200 nm to 300 nm.

The increase in the specific surface area increases the coating area of the shell part, which will be described below, so that dispersibility and movement speed of the electrophoretic particles can be improved.

In addition, the core part11may increase the light absorptivity of the core part and decrease the light reflectance by the plurality of grooves and/or protrusions formed on the surface of the core part.

In detail, by the plurality of grooves and/or protrusions formed in the core part11, it is possible to increase the absorption of light incident to the electrophoretic particles and decrease the light reflectance.

In addition, the core part11may improve the chromaticity index (L*) of the core part by grooves and/or protrusions formed on the surface of the core part.

Meanwhile, the surface of the core part11may be modified by a surface treatment process. In detail, the surface of the core part11is modified before the shell coating, so that it can be divided into a core11aand a surface treatment layer11b.

In detail, the shell part12described above is formed on the outer surface of the core part11. That is, the outer surface of the core part11may be coated with a polymer material constituting the shell part12. In detail, the shell part12may be formed through silane coating, and the surface of the core part11may be substituted with a hydroxyl group (—OH) or a carboxyl group (—COOH) that is easily reactive with the silane coupling agent.

Accordingly, the surface of the core part11is modified by being substituted with a hydroxyl group (—OH) or a carboxyl group (—COOH), and the shell part12may be formed on the surface of the core part11by silane coating.

The surface of the core part11may be modified by various methods. For example, by putting the core part11containing the carbon black in an acidic solution such as acetic acid, and the acidic solution and the surface of the core part react, the surface of the core part11may be substituted with a hydroxyl group (—OH).

Alternatively, the core part11whose surface is substituted with the hydroxyl group (—OH) is placed in an acidic solution having at least6carbon chains (for example oleic acid). By esterification of the core part and the oleic acid, the surface of the core part11may be substituted with a carboxyl group (—COOH).

The shell part12may be coated on the surface of the core part11to impart a surface charge to the electrophoretic particles.

In detail, when a silane coupling agent is coated on the surface of the core part whose surface is substituted with a hydroxyl group or a carboxyl group, the silane and the hydroxyl group or the silane and the carboxyl group react. Accordingly, the shell part12may be coated on the surface of the core part11.

Thereby, the electrophoretic particles can have dispersibility in the dispersion, and can move in a specific polar direction in the dispersion when a voltage is applied by a surface charge.

The silane coating on which the shell part is formed may be related to a specific surface area of the core part11. That is, as the specific surface area of the core part11increases, in proportion to this, the area on which the silane can be coated may increase.

Accordingly, the electrophoretic particles according to the embodiment increase the specific surface area of the core part11. Accordingly, the coating area of the shell part12coated on the surface of the core part11may be increased. Accordingly, by increasing the area of the shell part12coated on the surface of the core part11, dispersibility and surface charge characteristics by the shell part.

Hereinafter, the present invention will be described in more detail through electrophoretic particles according to Examples and Comparative Examples. These embodiments are merely presented as examples in order to explain the present invention in more detail. Therefore, the present invention is not limited to these examples.

EXAMPLE 1

The surface of the carbon black particles was etched using an alkali solution.

FIG.3is a view showing a scanning electron microscope photograph of carbon black particles whose surface has been etched by a chemical etching method.

Then, after measuring the specific surface area of the carbon black particles, the surface of the carbon black particles was modified. In detail, the carbon black particles were reacted with an acidic solution such as acetic acid to substituted the surface of the carbon black particles with a hydroxyl group (—OH).

Then, the carbon black particles were reacted with a silane coupling agent to form a charge coating layer on the surface of the carbon black particles to prepare electrophoretic particles.

Then, the light absorptance, light reflectance, chromaticity index (L*), and optical density of the electrophoretic particles were measured in the wavelength band of the visible light region.

EXAMPLE 2

A plurality of nano carbon black particles was aggregated to form carbon black.

FIG.4is a view showing a scanning electron microscope photograph of carbon black particles formed by agglomeration of nano carbon black particles.

Then, after measuring the specific surface area of the carbon black particles, the surface of the carbon black particles was modified in the same manner as in Example 1, and then a charge coating layer was formed on the surface of the carbon black particles to prepare electrophoretic particles.

Then, the light absorptance, light reflectance, chromaticity index (L*), and optical density of the electrophoretic particles were measured in the wavelength band of the visible light region.

Comparative Example 1

Spherical carbon black particles having no pattern formed on the surface were prepared.

FIG.5is a view showing a scanning electron microscope photograph of spherical carbon black particles on which a surface pattern is not formed.

Then, after measuring the specific surface area of the carbon black particles, the surface of the carbon black particles was modified in the same manner as in Example 1, and then a charge coating layer was formed on the surface of the carbon black particles to prepare electrophoretic particles.

Then, the light absorptance, light reflectance, chromaticity index (L*), and optical density of the electrophoretic particles were measured in the wavelength band of the visible light region.

TABLE 1light reflectance (%)ComparativeWavelength (nm)Example 1Example 1Example 240085.144490.718993.503245085.798491.322293.925550086.066691.809194.266455086.022492.051594.436160085.817292.116194.481365085.516592.048994.434270085.225091.908394.3358

TABLE 2light reflectance (%)ComparativeWavelength (nm)Example 1Example 1Example 240014.85569.28106.496745014.20168.67776.074450013.93348.19085.733555013.97767.94845.563960014.18287.88385.518665014.48357.95105.565770014.77508.09165.6641

TABLE 3chromaticity index (L*)ComparativeWavelength (nm)Example 1Example 1Example 2550121.600.92

TABLE 4ComparativeExample 1Example 1Example 2specific surface area60266611(m2/g)

TABLE 5optical densityComparativeCarbon content (wt %)Example 1Example 1Example 24000.20.230.264500.250.30.345000.320.360.43

Referring to Table 4, the specific surface area of the carbon black particles of the electrophoretic particles according to Examples 1 and 2 is greater than the specific surface area of the carbon black particles of the electrophoretic particles according to Comparative Example 1.

Accordingly, as described above, the specific surface area of the carbon black particles constituting the core is increased, and thus the coating area of the charge coating layer coated on the outer surface of the carbon black particles is increased.

Accordingly, the dispersibility of the electrophoretic particles according to the charge in the dispersion and the movement speed in the dispersion are improved.

In addition, referring to Tables 1 and 2, the electrophoretic particles according to Examples 1 and 2 have lower light reflectance and higher light absorption than the electrophoretic particles according to Comparative Example 1.

That is, the electrophoretic particles according to Examples 1 and 2 have a light absorptivity of 90% or more, that is, 90% to 99%, in a visible light wavelength region of 400 nm to 700 nm, and a light reflectance of 10% or less.

In addition, referring to Table 3, the electrophoretic particles according to Examples 1 and 2 have a smaller chromaticity index (L) value than the electrophoretic particles according to Comparative Examples. That is, the electrophoretic particles according to Examples 1 and 2 are closer to black than the electrophoretic particles according to Comparative Examples. That is, the electrophoretic particles according to the embodiment have a chromaticity index of 2 or less. In detail, the electrophoretic particles according to the embodiment have a chromaticity index of 2 or less. More specifically, the electrophoretic particles have a chromaticity index of 0 to 2.

In addition, referring to Table 5, the electrophoretic particles according to Examples 1 and 2 have a higher optical density than the electrophoretic particles according to Comparative Example 1.

Accordingly, since the light absorption rate is increased and the light reflectance is decreased, the same light blocking effect can be realized while reducing the amount of electrophoretic particles added to the dispersion.

Accordingly, it is possible to inhibit aggregation of the electrophoretic particles in the dispersion, thereby improving dispersibility, and increasing the movement speed, thereby improving the driving speed of a display device to which the electrophoretic particles are applied.

In addition, in the electrophoretic particles according to Examples 1 and 2, as optical density and chromaticity index are improved, only a smaller amount of electrophoretic particles is required. Accordingly, by reducing the thickness of the light conversion unit of the light route control member to which the electrophoretic particles are applied, it is possible to reduce the overall thickness of the light route control member.

Hereinafter, a switchable device including the electrophoretic particles described above will be described with reference toFIGS.6to14.

Referring toFIGS.6to8, a light route control member according to an embodiment may include a first substrate110, a second substrate120, a first electrode210, a second electrode220, and a light conversion unit300

The first substrate110may support the first electrode210. The first substrate110may be rigid or flexible.

In addition, the first substrate110may be transparent. For example, the first substrate110may include a transparent substrate capable of transmitting light.

The first substrate110may include glass, plastic, or a flexible polymer film. For example, the flexible polymer film may be made of any one of polyethylene terephthalate (PET), polycarbonate (PC), acrylonitrile-butadiene-styrene copolymer (ABS), polymethyl methacrylate (PMMA), polyethylene naphthalate (PEN), polyether sulfone (PES), cyclic olefin copolymer (COC), triacetylcellulose (TAC) film, polyvinyl alcohol (PVA) film, polyimide (PI) film, and polystyrene (PS), which is only an example, but the embodiment is not limited thereto.

In addition, the first substrate110may be a flexible substrate having flexible characteristics.

Further, the first substrate110may be a curved or bended substrate. That is, the light route control member including the first substrate110may also be formed to have flexible, curved, or bent characteristics. Accordingly, the light route control member according to the embodiment may be changed to various designs.

The first substrate110may have a thickness of about 1 mm or less.

The first electrode210may be disposed on one surface of the first substrate110. In detail, the first electrode210may be disposed on an upper surface of the first substrate110. That is, the first electrode210may be disposed between the first substrate110and the second substrate120.

The first electrode210may contain a transparent conductive material. For example, the first electrode210may contain a metal oxide such as indium tin oxide, indium zinc oxide, copper oxide, tin oxide, zinc oxide, titanium oxide, etc.

The first electrode210may be disposed on the first substrate110in a film shape. In detail, light transmittance of the first electrode210may be about 80% or more.

The first electrode210may have a thickness of about 10 nm to about 50 nm.

Alternatively, the first electrode210may contain various metals to realize low resistance. For example, the first electrode210may contain at least one metal of chromium (Cr), nickel (Ni), copper (Cu), aluminum (Al), silver (Ag), molybdenum (Mo). gold (Au), titanium (Ti), and alloys thereof.

In addition, the first electrode210may include a plurality of conductive patterns. For example, the first electrode210may include a plurality of mesh lines intersecting each other and a plurality of mesh openings formed by the mesh lines.

Accordingly, even though the first electrode210contains a metal, visibility may be improved because the first electrode is not visible from the outside. In addition, the light transmittance is increased by the openings, so that the brightness of the light route control member according to the embodiment may be improved.

The second substrate120may be disposed on the first substrate110. In detail, the second substrate120may be disposed on the first electrode210on the first substrate110.

The second substrate120may contain a material capable of transmitting light. The second substrate120may contain a transparent material. The second substrate120may contain a material the same as or similar to that of the first substrate110described above.

For example, the second substrate120may include glass, plastic, or a flexible polymer film. For example, the flexible polymer film may be made of any one of polyethylene terephthalate (PET), polycarbonate (PC), acrylonitrile-butadiene-styrene copolymer (ABS), polymethyl methacrylate (PMMA), polyethylene naphthalate (PEN), polyether sulfone (PES), cyclic olefin copolymer (COC), triacetylcellulose (TAC) film, polyvinyl alcohol (PVA) film, polyimide (PI) film, and polystyrene (PS), which is only an example, but the embodiment is not limited thereto.

In addition, the second substrate120may be a flexible substrate having flexible characteristics.

Further, the second substrate120may be a curved or bended substrate. That is, the light route control member including the second substrate120may also be formed to have flexible, curved, or bent characteristics. Accordingly, the light route control member according to the embodiment may be changed to various designs.

The second substrate120may have a thickness of about 1 mm or less.

The second electrode220may be disposed on one surface of the second substrate120. In detail, the second electrode220may be disposed on a lower surface of the second substrate120. That is, the second electrode220may be disposed on a surface on which the second substrate120faces the first substrate110. That is, the second electrode220may be disposed facing the first electrode210on the first substrate110. That is, the second electrode220may be disposed between the first electrode210and the second substrate120.

The second electrode220may contain a transparent conductive material. For example, the second electrode220may contain a metal oxide such as indium tin oxide, indium zinc oxide, copper oxide, tin oxide, zinc oxide, titanium oxide, etc.

The second electrode220may be disposed on the first substrate110in a film shape. In addition, the light transmittance of the second electrode220may be about 80% or more.

The second electrode220may have a thickness of about 10 nm to about 50 nm.

Alternatively, the second electrode220may contain various metals to realize low resistance. For example, the second electrode220may contain at least one metal of chromium (Cr), nickel (Ni), copper (Cu), aluminum (Al), silver (Ag), molybdenum (Mo). gold (Au), titanium (Ti), and alloys thereof.

In addition, the second electrode220may include a plurality of conductive patterns. For example, the second electrode220may include a plurality of mesh lines intersecting each other and a plurality of mesh openings formed by the mesh lines.

Accordingly, even though the second electrode220contains a metal, visibility may be improved because the second electrode220is not visible from the outside. In addition, the light transmittance is increased by the openings, so that the brightness of the light route control member according to the embodiment may be improved.

The light conversion unit300may be disposed between the first substrate110and the second substrate120. In detail, the light conversion unit300may be disposed between the first electrode210and the second electrode220.

Referring toFIGS.9to14, the light conversion unit300may include a partition wall unit310and a receiving unit320.

The partition wall unit310may be defined as a partition wall region for partitioning a region of receiving unit320. And the receiving unit320may be defined as a variable region that is variable to a light blocking unit and a light transmitting unit according to application of voltage.

The partition wall unit310and the receiving unit320may be alternately disposed. The partition wall unit310and the receiving unit320may be disposed in different widths. For example, the width of the receiving unit320may be greater than the width of the receiving unit320.

The partition wall unit310and the receiving unit320may be alternately disposed. In detail, the partition wall unit310and the receiving unit320may be alternately disposed. That is, each of the partition wall units310may be disposed between the receiving units320adjacent to each other, and each of the receiving units320may be disposed between the partition wall units310adjacent to each other.

The partition wall unit310may contain a transparent material. The partition wall unit310may contain a material that may transmit light.

The partition wall unit310may contain a resin material. For example, the partition wall unit310may contain a photo-curable resin material. As an example, the partition wall unit310may contain a UV resin or a transparent photoresist resin. Alternatively, the partition wall unit310may contain urethane resin or acrylic resin.

The partition wall unit310may transmit light incident on any one of the first substrate110and the second substrate120toward another substrate.

For example, inFIGS.9to14, light may be emitted in a direction of the first substrate110and the light may be incident in the direction of the second substrate120. The partition wall unit310may transmit the light, and the transmitted light may be moved in a direction of the second substrate120.

The receiving units320may include the dispersion320aand the light conversion particles10described above. In detail, the receiving unit320is filled with the dispersion320a, and a plurality of the light conversion particles10may be dispersed in the dispersion320a.

The dispersion320amay be a material for dispersing the light conversion particles10. The dispersion320amay contain a transparent material. The dispersion320amay contain a non-polar solvent. In addition, the dispersion320amay contain a material capable of transmitting light. For example, the dispersion320amay include at least one of a halocarbon-based oil, a paraffin-based oil, and isopropyl alcohol.

The electrophoretic particles10may be disposed to be dispersed in the dispersion320a. In detail, the plurality of electrophoretic particles10may be disposed to be spaced apart from each other in the dispersion320a.

The electrophoretic particles10may have a particle diameter of about 50 nm to about 800 nm. Preferably, the electrophoretic particles10may be formed to have a particle diameter of about 200 nm to about 300 nm. When the particle diameter of the electrophoretic particles10is less than about 50 nm, the electrophoretic particles10may agglomerate to reduce dispersibility. And when the particle diameter of the electrophoretic particles10exceeds about 800 nm, the movement speed in the dispersion may be reduced due to an increase in the mass of the electrophoretic particles.

Meanwhile, as described above, the electrophoretic particles10increase the specific surface area of the core part, thereby increasing the coating area of the polymer charge coating layer coated on the core portion. Thereby, while maintaining the particle diameter of the electrophoretic particles10, it is possible to improve the dispersibility and movement speed.

In detail, the driving speed of the light route member may be defined by Equation 1 below, and the moving speed of the electrophoretic particles in the dispersion may be defined by Equation 2 below.

tswitch=h2μ⁢V[Formula⁢1]h: distance between electrodes (height of partition wall unit)μ: moving speedV: diving vortage

μ=2⁢ε⁢ε0⁢ζ3⁢η[Formula⁢2]ε: permittivityζ: surface chargeη: viscosity

Referring to Equations 1 and 2, the driving speed of the light route control member is improved as the moving speed of the electrophoretic particles increases, and the moving speed of the electrophoretic particles is proportional to the amount of surface charge.

That is, the electrophoretic particles can increase the surface charge amount of the electrophoretic particles by increasing the coating area of the polymer charge coating layer related to the surface charge amount due to the increase in the specific surface area of the core.

Accordingly, the moving speed of the electrophoretic particles is increased, and the driving speed of the light route control member to which the electrophoretic particles are applied can also be shortened.

The light transmittance of the receiving unit320may be changed by the electrophoretic particles10. In detail, the receiving unit320may be changed into the light blocking part and the light transmitting part by changing the light transmittance due to the movement of the electrophoretic particles10.

For example, the light route control member according to the embodiment may be changed from a first mode to a second mode or from the second mode to the first mode by a voltage applied to the first electrode210and the second electrode220.

In detail, in the light route control member according to the embodiment, the receiving unit320becomes the light blocking part in the first mode, and light of a specific angle may be blocked by the receiving unit320. That is, a viewing angle of the user viewing from the outside may be narrowed.

In addition, in the light route control member according to the embodiment, the receiving unit320becomes the light transmitting part in the second mode, and in the light route control member according to the embodiment, light may be transmitted through both the partition wall unit310and the receiving unit320. That is, the viewing angle of the user viewing from the outside may be widened.

Switching from the first mode to the second mode, that is, the conversion of the receiving unit320from the light blocking part to the light transmitting part may be realized by movement of the electrophoretic particles10of the receiving unit320.

In detail, the receiving unit320may be electrically connected to the first electrode210and the second electrode220.

In this case, when a voltage is not applied to the light route control member from the outside, the electrophoretic particles10of the receiving unit320are uniformly dispersed in the dispersion320a, and light may be blocked by the electrophoretic particles in the receiving unit320. Accordingly, in the first mode, the receiving unit320may be driven as the light blocking part.

Alternatively, when a voltage is applied to the light route control member from the outside, the electrophoretic particles10may move. For example, the electrophoretic particles10may move toward one end or the other end of the receiving unit320by a voltage transmitted through the first electrode210and the second electrode220. That is, the electrophoretic particles10may move from the receiving unit320toward the first electrode or the second electrode.

In detail, when a voltage is applied to the first electrode210and/or the second electrode220, an electric field is formed between the first electrode210and the second electrode220, and the charged carbon black, that is, the electrophoretic particles may be moved toward a positive electrode of the first electrode210and the second electrode220using the dispersion320aas a medium.

That is, when the voltage is not applied to the first electrode210and/or the second electrode220, as shown inFIGS.10,12,14, the electrophoretic particles10may be uniformly dispersed in the dispersion320ato drive the receiving unit320as the light blocking part

In addition, when the voltage is applied to the first electrode210and/or the second electrode220, as shown inFIGS.9,11,13, the electrophoretic particles10may be moved toward the first electrode210in the dispersion320a. That is, the electrophoretic particles10are moved in one direction, and the receiving unit320may be driven as the light transmitting part

Accordingly, the light route control member according to the embodiment may be driven in two modes according to a user's surrounding environment. That is, when the user requires light transmission only at a specific viewing angle, the receiving unit is driven as the light blocking part, or in an environment in which the user requires high brightness, a voltage may be applied to drive the receiving unit as the light transmitting part.

Therefore, since the light route control member according to the embodiment may be implemented in two modes according to the user's requirement, the light route control member may be applied regardless of the user's environment.

Meanwhile, the receiving unit320may be formed in various shapes.

In addition, referring toFIGS.9and10, the receiving unit320extends from one end of the receiving unit320to the other end, and the width of the receiving unit320may be changed.

For example, referring toFIGS.9and10, the receiving unit320may be formed in a trapezoidal shape. In detail, the receiving unit320may be formed so that the width of the receiving unit320is widened while extending from the first electrode210to the second electrode220.

That is, the width of the receiving unit320may be narrowed while extending in the opposite direction from the user's viewing surface. Also, when a voltage is applied to the light transmitting part, the light-absorbing particles of the receiving unit320may move in a direction in which the width of the receiving unit is narrowed.

That is, the width of the receiving unit320may be increased while extending from the light incident part to which the light is incident to the light output part from which the light is emitted.

Accordingly, since the electrophoretic particles move in a direction opposite to the viewing surface rather than the viewing surface, blocking of light emitted in the viewing surface direction can be inhibited, thereby improving the luminance of the light route control member.

In addition, since the electrophoretic particles move from a wide region to a narrow region, the electrophoretic particles may be easily moved.

In addition, since the electrophoretic particles move to a narrow area of the receiving unit, the amount of light transmitted in the direction of the user's viewing surface is increased, thereby improving the front luminance.

Alternatively, on the contrary, the receiving unit320may be formed to extend from the first electrode210to the second electrode220and to have a narrow width of the receiving unit320.

That is, the width of the receiving unit320may be widened while extending from the user's viewing surface to the opposite surface direction. In addition, when a voltage is applied to the light transmitting part, the electrophoretic particles of the receiving unit320may move in a direction in which the width of the receiving unit is widened.

That is, the width of the receiving unit320may be narrowed while extending from the light incident part to which the light is incident to the light output part from which the light is emitted.

Accordingly, the contact area between the first electrode and one surface of the receiving unit through which the electrophoretic particles move is increased, so that the moving speed of the light electrophoretic particles, that is, the driving speed may be increased.

Meanwhile, the receiving unit320may be disposed to be spaced apart from the first electrode210or the second electrode220. That is, the receiving unit320may be disposed in contact with only one of the first electrode210and the second electrode220.

For example, referring toFIGS.11and12, the receiving unit320may be spaced apart from the first electrode210.

The same or similar material to the partition wall310may be disposed in a region where the receiving unit320and the first electrode210are spaced apart from each other.

In addition, the receiving unit320may be disposed with an inclination angle θ. In detail, referring toFIGS.13and14, the receiving part320may be disposed with an inclination angle θ of greater than 0° to less than 90° with respect to the first electrode210In detail, the receiving unit320may extend upwardly while having an inclination angle θ of greater than 0° to less than 90° with respect to one surface of the first electrode210.

Accordingly, when the light route control member is used together with the display panel, moire caused by overlapping of the pattern of the display panel and the receiving unit320of the light path member may be inhibited, thereby improving user visibility.

In detail, the display panel may include pixel patterns extending in one direction. Accordingly, the pixel pattern and the pattern of the receiving unit320of the light route member may overlap to generate a moire phenomenon. However, by tilting the receiving unit pattern at a predetermined angle and disposing it, such a moire phenomenon may be inhibited.

That is, the receiving unit pattern and the pixel pattern may be disposed to cross each other, and in this case, the receiving unit pattern and the pixel pattern may be disposed to cross each other at an angle of greater than 0° to less than 90°.

Hereinafter, the present invention will be described in more detail through electrophoretic particles according to Examples and Comparative Examples. These embodiments are merely presented as examples in order to explain the present invention in more detail. Therefore, the present invention is not limited to these examples.

EXAMPLE 3

A first electrode was formed on the first substrate, and a second electrode was formed under the second substrate. Then, a plurality of receiving units partitioned by a partition wall unit between the first and second electrodes were formed to form an light route control member.

At this time, the receiving unit contained paraffinic oil and the electrophoretic particles of Example 1 dispersed in paraffinic oil.

Then, a DC 5V voltage was applied to the optical path control member, and it was observed whether the transmittance of the receiving unit was varied.

EXAMPLE 4

After forming the light route control member in the same manner as in Example 3 except that the electrophoretic particles of Example 2 were dispersed in the receiving part, it was observed whether the transmittance of the receiving part was changed.

Comparative Example 2

After the light route control member was formed in the same manner as in Example 3 except that the electrophoretic particles of Comparative Example 1 were dispersed in the receiving part, it was observed whether the transmittance of the receiving part was changed.

TABLE 6ComparativeExample 3Example 4Example 2Driving time (s)113.514Transmittance14.6815.2513.05variable rate (%)Driving speed1.334.360.93(%/s)

Referring to Table 6, the light route control member of Examples 3 and 4 has a higher driving speed and improved transmittance variable rate, compared to the light route control member of Comparative Example 2.

That is, since the light route control member of Examples 3 and 4 includes the electrophoretic particles having improved specific surface areas, the transmittance variability increases due to the improvement of the absorptivity of the electrophoretic particles and the reduction of the reflectance.

In addition, since the light path controlling member of Examples 3 and 4 includes the electrophoretic particles having improved specific surface area, the moving speed of the electrophoretic particles can be improved, thereby improving the driving speed of the light route control member.

Hereinafter, a light route control member according to another embodiment will be described with reference toFIGS.15to28. In the description of the light route control member according to another embodiment, descriptions of the same contents as those of the above-described embodiment will be omitted, and the same reference numerals will be given to the same components. In addition, the light route control member according to another embodiment may be combined with the light route control member according to the above-described embodiment.

In the light route control member according to another embodiment, a plurality of patterns may be formed on a substrate.

Referring toFIG.15, a plurality of patterns may be formed on the first substrate110. In detail, a plurality of first protruding patterns P1may be formed on any one surface of the first substrate110.

The first protruding patterns P1may include the same material as the first substrate110. The first protrusion pattern P1may be integrally formed with the first substrate110.

The first protruding patterns P1may be disposed to extend in one direction on the first substrate110. Referring toFIG.2, the first protruding patterns P1may be arranged to extend in the direction of the short width of the first substrate110in the direction of the arrow.

A first area1A in which the first protrusion pattern P1is disposed and a second area2A in which the first protrusion pattern P1is not disposed may be included on the first substrate110. In detail, the first protrusion pattern P1may be disposed only in an area overlapping the receiving unit of the light conversion part300to be described below. That is, the first area1A may overlap the area where the receiving unit is disposed, and the second area may overlap the area where the partition wall part of the light conversion part300is disposed.

In addition, referring toFIG.16, a plurality of patterns may be formed on the second substrate120. In detail, a plurality of second protrusion patterns P2may be formed on any one surface of the second substrate120.

The second protrusion patterns P2may include the same material as the second substrate120. The second protrusion pattern P2may be integrally formed with the second substrate120.

The second protruding patterns P2may be disposed to extend in one direction on the second substrate120. Referring toFIG.3, the second protruding patterns P2may be arranged to extend in the direction of the arrow and in the long width direction of the second substrate120. That is, the first protrusion pattern P1and the second protrusion pattern P2may be disposed to extend in different directions.

A third area3A in which the second protrusion pattern P2is disposed and a fourth area4A in which the second protrusion pattern P2is not disposed may be included on the second substrate120. In detail, the second protrusion pattern P2may be disposed only in an area overlapping the receiving unit of the light conversion part300to be described below. That is, the third area3A may overlap the area where the receiving unit is disposed, and the fourth area may overlap the area where the partition wall part of the light conversion part300is disposed.

That is, the first region1A of the first substrate110and the third region3A of the second substrate120overlap each other, and the second region of the first substrate110. (2A) and the fourth region4A of the second substrate120may overlap each other.

Referring toFIG.17, the first electrode210may be disposed on the same surface as the first protruding pattern P1. That is, the first electrode210and the first protrusion pattern P1may be disposed on the same surface of the first substrate110.

In detail, the first protrusion pattern P1may be disposed on a first region of the first substrate110, and the first electrode210may be disposed on a second region of the first substrate110. That is, the first electrode210may be disposed on a region overlapping the receiving unit of the light conversion part300. That is, the first electrode210may be disposed as a plurality of pattern electrodes on one surface of the first substrate.

In addition, referring toFIG.18, the second electrode220may be disposed on the same surface as the second protrusion pattern P2. That is, the second electrode220and the second protrusion pattern P2may be disposed on the same surface of the second substrate120.

In detail, the second protrusion pattern P2may be disposed on a third region of the second substrate120, and the second electrode220may be disposed on a fourth region of the second substrate120. That is, the second electrode220may be disposed on an area overlapping the receiving unit of the light conversion part300. That is, the second electrode220may be disposed as a plurality of pattern electrodes on one surface of the second substrate.

Alternatively, referring toFIG.19, a first electrode210may be disposed on one surface of the first substrate110.

The first electrode210may be disposed on a different surface from the first protruding pattern P1. That is, the first electrode210and the first protrusion pattern P1may be respectively disposed on opposite surfaces of the first substrate110.

In detail, the first protrusion pattern P1is disposed on one surface of the first substrate110, and the first electrode210is disposed on the other surface opposite to one surface of the first substrate110.

In addition, the first electrode210may be disposed as a surface electrode on the other surface of the first substrate110. That is, the first electrode210may be disposed on the first and second regions of the first substrate110on the other surface of the first substrate110.

Accordingly, the process of separately patterning the first electrode210may be omitted.

Also, referring toFIG.20, a second electrode220may be disposed on one surface of the second substrate120.

The second electrode220may be disposed on a surface different from that of the second protrusion pattern P2. That is, the second electrode220and the second protrusion pattern P2may be respectively disposed on opposite surfaces of the second substrate120.

In detail, the second protrusion pattern P2is disposed on one surface of the second substrate120, and the second electrode220is disposed on the other surface opposite to one surface of the second substrate120.

In addition, the second electrode220may be disposed as a surface electrode on the other surface of the second substrate120. That is, the second electrode220may be disposed on the third and fourth regions of the second substrate120on the other surface of the second substrate120.

Accordingly, the process of separately patterning the second electrode220may be omitted.

The first substrate110and the second substrate120may include the first protrusion patterns P1and the second protrusion pattern P2described above, respectively.

Referring toFIGS.21to28, the patterns may be disposed at various positions depending on the relationship between the first substrate110, the second substrate120, and the light conversion unit300.

Referring toFIGS.21and22, the first protrusion pattern P1and the second protrusion pattern P2may be disposed to face each other. That is, the first protrusion pattern P1is disposed between the light conversion unit300and the first substrate110, and the second protrusion pattern P2is disposed between the light conversion unit300and the second substrate110.

The first electrode210and the first protrusion pattern P1may be disposed on the first substrate110. The first electrode210may be disposed between the first protruding patterns P1, and the first protruding pattern P1may be disposed between the first electrodes210.

The first protrusion pattern P1may be disposed in a region overlapping the partition wall unit310. In addition, the first electrode210may be disposed in a region overlapping the receiving unit320.

The first electrode210may be disposed on a region overlapping the receiving unit320to apply a voltage to the receiving unit320.

The first protrusion pattern P1may collect light moving in the direction of the partition wall unit310. In detail, the light may be emitted from the lower direction of the first substrate110and may be incident in the direction of the light conversion unit300. The first protrusion pattern P1may focus the light moving to the light conversion unit to increase the straightness of the light. That is, the first protrusion pattern may play the same role as the first prism substrate of the backlight module.

The second electrode220and the second protrusion pattern P2may be disposed on the second substrate120. The second electrode220may be disposed between the second protruding patterns P1, and the second protruding pattern P2may be disposed between the second electrodes220.

The second protrusion pattern P2may be disposed in an area overlapping the partition wall part310. In addition, the second electrode220may be disposed in a region overlapping the receiving unit320.

The second electrode220may be disposed on a region overlapping the receiving unit to apply a voltage to the receiving unit.

The second protrusion pattern P2may collect light moving in the direction of the partition wall part310. In detail, the light may be emitted from the lower direction of the second substrate120and may be incident in the direction of the light conversion unit300. The second protrusion pattern P2may focus the light moving to the light conversion unit to increase the straightness of the light. That is, the second protrusion pattern may serve as a second prism substrate of the backlight module.

That is, the first and second protrusion patterns may serve as a prism substrate of the backlight module. Accordingly, when the light path control member is combined with another member and applied to a display device, the prism substrate of the backlight module for supplying the light source may be omitted.

Accordingly, when the light route control member is applied to the display device, some components included in the display device may be omitted, thereby reducing the thickness of the display device and increasing the light transmittance according to the decrease in the thickness.

In addition, adhesion between the light conversion unit on the first substrate110and the adhesive layer on the light conversion unit may be improved by the first and second protrusion patterns. That is, the surface roughness of the first and second substrates may be increased by the first and second protrusion patterns. Accordingly, a contact area in contact with the light conversion unit and the adhesive layer is increased, so that the first and second substrates and adhesion between the light conversion unit and the adhesive layer may be improved.

In addition, referring toFIGS.23and24, the first protrusion pattern P1may be disposed on one surface of the first substrate110, and the second protrusion pattern P2may be disposed on one surface of the second substrate120.

The first protrusion pattern P1may be disposed on a surface different from that of the first electrode210. In detail, the first electrode210may be disposed on the upper surface of the first substrate110, and the first protruding pattern P1may be disposed on the lower surface of the first substrate110.

Also, the second protrusion pattern P2may be disposed on a surface different from that of the second electrode220. In detail, the second electrode220may be disposed on the lower surface of the second substrate120, and the second protruding pattern P2may be disposed on the upper surface of the second substrate120.

The first electrode210and the second electrode220may be disposed as a surface electrode on one surface of the first substrate and the second substrate, respectively. That is, the first electrode210and the second electrode220may be disposed in a region overlapping the partition wall unit310and the receiving unit320of the light conversion unit. By disposing the electrode and the protrusion pattern on different surfaces of the substrate, a process of separately patterning the first and second electrodes may be omitted.

In addition, referring toFIGS.25and26, the first protrusion pattern P1may be disposed on one surface of the first substrate110, and the second protrusion pattern P2may be formed on one surface of the second substrate120.

The first protrusion pattern P1may be disposed on a surface different from that of the first electrode210. In detail, the first electrode210may be disposed on the upper surface of the first substrate110, and the first protruding pattern P1may be disposed on the lower surface of the first substrate110.

Also, the second protrusion pattern P2may be disposed on the same surface as the second electrode220. In detail, the second electrode220and the second protrusion pattern P2may be disposed on the lower surface of the second substrate120.

That is, the first electrode210may be disposed to face the second electrode220and the second protrusion pattern P2.

The first electrode210may be disposed as a surface electrode on one surface of the first substrate. Also, the second electrode220may be disposed as a plurality of pattern electrodes on one surface of the second substrate. That is, the first electrode210may be disposed on a region overlapping the partition wall unit310and the receiving unit320of the light conversion unit, and the second electrode220may be only disposed on a region overlapping the receiving unit320of the light conversion unit.

In addition, referring toFIGS.27and28, the first protruding pattern P1may be disposed on one surface of the first substrate110, and the second protruding pattern P2may be disposed on one surface of the second substrate120.

The first protrusion pattern P1may be disposed on the same surface as the first electrode210. In detail, the first electrode210and the first protrusion pattern P1may be disposed on the upper surface of the first substrate110.

Also, the second protrusion pattern P2may be disposed on a surface different from that of the second electrode220. In detail, the second electrode220may be disposed on the lower surface of the second substrate120, and the second protruding pattern P2may be disposed on the upper surface of the second substrate120.

That is, the second electrode220may be disposed to face the first electrode210and the first protrusion pattern P1.

The second electrode220may be disposed as a surface electrode on one surface of the second substrate. Also, the first electrode210may be disposed as a plurality of pattern electrodes on one surface of the first substrate. That is, the second electrode220may be disposed on a region overlapping the partition wall unit310and the receiving unit320of the light conversion unit, and the first electrode210may be only disposed the receiving unit320of the light conversion unit.

The light route control member according to another embodiment may include a plurality of protrusion patterns protruding from one surface of the first and second substrates on which the electrodes are disposed.

In detail, the first protrusion pattern may be disposed on the first substrate, and the second protrusion pattern may be disposed on the second substrate. The first and second protrusion patterns may extend in different directions and may serve to collect light moving from the first substrate to the second substrate.

That is, the plurality of protrusion patterns formed on the first and second substrates may have the same function as the prism sheet of the backlight module.

Accordingly, when the light route control member is used in combination with the backlight module, the prism substrate for condensing light in the backlight module may be omitted. Accordingly, it is possible to reduce the thickness of the display device and to reduce light loss occurring while passing through the prism substrate.

In addition, by increasing the surface roughness of the first and second substrates by the first and second protruding members, a contact area between the light conversion unit and the adhesive layer in close contact with the first and second substrates may be increased. Accordingly, it is possible to have an improved adhesion.

Accordingly, the light route control member and the display device including the same according to the embodiment may be formed to have a thin thickness, and may have improved front luminance and reliability.

Hereinafter, referring toFIGS.29to31, a display device and a display apparatus to which a light route control member according to an embodiment is applied will be described.

Referring toFIG.29, a light route control member1000according to an embodiment may be disposed on a display panel2000.

The display panel2000and the light route control member1000may be disposed to be adhered to each other. For example, the display panel2000and the light route control member1000may be adhered to each other via an adhesive layer1500. The adhesive layer1500may be transparent. For example, the adhesive layer1500may include an adhesive or an adhesive layer containing an optical transparent adhesive material.

The adhesive layer1500may include a release film. In detail, when adhering the light route control member and the display panel, the light route control member and the display panel may be adhered after the release film is removed.

The display panel2000may include a first substrate2100and a second substrate2200. When the display panel2000is a liquid crystal display panel, the light route control member may be formed under the liquid crystal panel. That is, when the user-viewed side of the liquid crystal panel is defined as the upper portion of the liquid crystal panel, the light route control member may be disposed below the liquid crystal panel. The display panel2000may be formed in a structure in which the first substrate2100including a thin film transistor (TFT) and a pixel electrode and the second substrate2200including color filter layers are bonded with a liquid crystal layer interposed therebetween.

In addition, the display panel2000may be a liquid crystal display panel of a color filter on transistor (COT) structure in which a thin film transistor, a color filter, and a black matrix are formed at the first substrate2100and the second substrate2200is bonded to the first substrate2100with the liquid crystal layer interposed therebetween. That is, a thin film transistor may be formed on the first substrate2100, a protective film may be formed on the thin film transistor, and a color filter layer may be formed on the protective film. In addition, a pixel electrode in contact with the thin film transistor may be formed on the first substrate2100. At this point, in order to improve an aperture ratio and simplify a masking process, the black matrix may be omitted, and a common electrode may be formed to function as the black matrix.

In addition, when the display panel2000is the liquid crystal display panel, the display device may further include a backlight unit providing light from a rear surface of the display panel2000. The backlight unit may be disposed under the light route control member.

That is, as shown inFIG.29, the light route control member may be disposed under the liquid crystal panel.

Alternatively, when the display panel2000is an organic light emitting display panel, the light route control member may be formed on the organic light emitting display panel. That is, when the surface viewed by the user of the organic light emitting display panel is defined as the upper portion of the organic light emitting display panel, the light route control member may be disposed on the organic light emitting display panel. The display panel2000may include a self-luminous element that does not require a separate light source. In the display panel2000, a thin film transistor may be formed on the first substrate2100, and an organic light emitting element in contact with the thin film transistor may be formed. The organic light emitting element may include an anode, a cathode, and an organic light emitting layer formed between the anode and the cathode. Further, the second substrate2200configured to function as an encapsulation substrate for encapsulation may further be included on the organic light emitting element.

Furthermore, although not shown in drawings, a polarizing plate may be further disposed between the light route control member1000and the display panel2000. The polarizing plate may be a linear polarizing plate or an external light reflection preventive polarizing plate. For example, when the display panel2000is a liquid crystal display panel, the polarizing plate may be the linear polarizing plate. Further, when the display panel2000is the organic light emitting display panel, the polarizing plate may be the external light reflection preventive polarizing plate.

In addition, an additional functional layer1300such as an anti-reflection layer, an anti-glare, or the like may be further disposed on the light route control member1000. Specifically, the functional layer1300may be adhered to one surface of the substrate of the light route control member. Although not shown in drawings, the functional layer1300may be adhered to the base100of the light route control member via an adhesive layer. In addition, a release film for protecting the functional layer may be further disposed on the functional layer1300.

Further, a touch panel may be further disposed between the display panel and the light route control member.

Although it is shown in the drawings that the light route control member is disposed at an upper portion of the display panel, but the embodiment is not limited thereto, and the light route control member may be disposed at various positions such as a position in which light is adjustable, that is, a lower portion of the display panel, between a second substrate and a first substrate of the display panel, or the like.

Referring toFIGS.29and30, the light route control member according to the embodiment may be applied to a vehicle.

Referring toFIGS.29and30, the light route control member according to the embodiment may be applied to a display device that displays a display.

For example, when power is not applied to the light route control member as shown inFIG.29, the receiving unit functions as the light blocking part, so that the display device is driven in a light blocking mode, and when power is applied to the light route control member as shown inFIG.30, the receiving unit functions as the light transmitting part, so that the display device may be driven in an open mode.

Accordingly, a user may easily drive the display device in a privacy mode or a normal mode according to application of power.

In addition, although not shown in the drawings, the display device to which the light route control member according to the embodiment is applied may also be applied inside the vehicle.

For example, the display device including the light route control member according to the embodiment may display a video confirming information of the vehicle and a movement route of the vehicle. The display device may be disposed between a driver seat and a passenger seat of the vehicle.

In addition, the light route control member according to the embodiment may be applied to a dashboard that displays a speed, an engine, an alarm signal, and the like of the vehicle.

Furthermore, the light route control member according to the embodiment may be applied to a front glass (FG) of the vehicle or right and left window glasses.

The characteristics, structures, effects, and the like described in the above-described embodiments are included in at least one embodiment of the present invention, but are not limited to only one embodiment. Furthermore, the characteristic, structure, and effect illustrated in each embodiment may be combined or modified for other embodiments by a person skilled in the art. Accordingly, it is to be understood that such combination and modification are included in the scope of the present invention.

In addition, embodiments are mostly described above, but the embodiments are merely examples and do not limit the present invention, and a person skilled in the art may appreciate that several variations and applications not presented above may be made without departing from the essential characteristic of embodiments. For example, each component specifically represented in the embodiments may be varied. In addition, it should be construed that differences related to such a variation and such an application are included in the scope of the present invention defined in the following claims.