Optical path control member and display having the same

Abstract

A light path control member according to an embodiment includes a first substrate, a first electrode provided on an upper portion of the first substrate, a second substrate provided on the first substrate, a second electrode provided on a lower portion of the second substrate, and a light conversion portion provided between the first electrode and the second electrode, wherein the light conversion portion includes partition wall portions and housing portions alternately provided. The housing portions have light transmittance that changes according to application of a voltage, the housing portions include a plurality of unit accommodation units spaced apart from each other, and include a dispersion liquid and light-absorbing particles dispersed in the dispersion liquid. The light-absorbing particles include first particles and second particles, wherein a particle diameter of the first particles is larger than a particle diameter of the second particles, and surfaces of the first particles and the second particles are charged with charges of the same polarity.

Description

TECHNICAL FIELD

[0001] Embodiments relate to a light path control member and a display having the same. BACKGROUND

[0002] The light blocking film blocks transmission of light from a light source and is attached to a front surface of a display panel, such that the light blocking film adjusts a viewing angle of light according to an incident angle of light to exhibit clear image quality at a viewing angle desired by a user when a display plays a picture, wherein the display panel is a display device for a mobile phone, a notebook computer, a tablet computer, a car navigation device, a vehicle touch, etc.

[0003] In addition, the light blocking film can be used for a window of a vehicle, a building, etc. to partially block external light to prevent glare or prevent the inside from being seen from the outside.

[0004] That is, the light blocking film can be a light path control member that controls a moving path of light, blocks light in a specific direction, and transmits light in a specific direction. Accordingly, by controlling a light transmission angle through the light blocking film, a viewing angle of a user can be controlled.

[0005] Meanwhile, such a light blocking film can be a light blocking film that can always control a viewing angle regardless of a surrounding environment or a user's environment, and a switchable light blocking film that allows a user to turn on / off viewing angle control according to a surrounding environment or a user's environment can be distinguished.

[0006] Such a switchable light blocking film can be implemented by adding electrically mobile particles to a pattern portion and changing the pattern portion to a light transmission portion and a light blocking portion through dispersion and aggregation of the particles.

[0007] On the other hand, according to the light blocking effect of the particles, the light blocking effect can be improved as the number of particles increases, but when the number of particles in a limited space increases, aggregation occurs between the particles, the moving speed is reduced due to the aggregation of the particles, and the viewing angle control effect can be reduced.

[0008] Therefore, there is a need for a light path control member having a new structure that can achieve an improved light blocking effect while adding the same number of particles. SUMMARY

[0009] TECHNICAL PROBLEM

[0010] Embodiments aim to provide a light path control member capable of preventing aggregation of electrophoretic particles while achieving an improved light blocking effect according to the electrophoretic particles, and a display device including the same.

[0011] TECHNICAL SOLUTION

[0012] The light path control member according to the embodiment includes a first substrate, a first electrode disposed on an upper surface of the first substrate, a second substrate disposed on the first substrate, a second electrode disposed on a lower surface of the second substrate, and a light conversion portion disposed between the first electrode and the second electrode, and the light conversion portion includes partition wall portions and accommodation portions alternately disposed, the accommodation portions include a plurality of unit receiving cells spaced apart from each other, the accommodation portions include a dispersion liquid and a plurality of light-absorbing particles dispersed in the dispersion liquid, the light-absorbing particles include first particles and second particles, a particle diameter of the first particles is larger than a particle diameter of the second particles, and surfaces of the first particles and the second particles are charged with the same polarity of electric charges.

[0013] Advantageous Effects

[0014] The light path control member according to the embodiment and the display device including the same can include electrophoretic particles having different particle diameters.

[0015] That is, in the case of light-absorbing particles including first particles and second particles having different particle diameters, they have an increased packing density compared to light-absorbing particles having the same particle diameter. Accordingly, it can be disposed to be gathered to a low height within the accommodation portion.

[0016] Accordingly, the aggregation height of the light-absorbing particles can be reduced, thereby increasing the light transmission area of the accommodation portion in the light path control member driven in a transmission mode by applying a voltage. Accordingly, by increasing the light transmission area in the transmission mode, the front brightness can be improved, thereby improving the visibility of the user.

[0017] Further, the light path control member according to the embodiment can have improved front transmittance.

[0018] Further, the light path control member according to the embodiment can have improved brightness uniformity.

[0019] In detail, when the light conversion portion is driven to a transmission portion by metal oxide particles that reflect and / or scatter light to light conversion particles disposed in the light conversion portion, the transmittance of the light conversion portion can be improved.

[0020] That is, by disposing light scattering particles in a region in which light-absorbing particles are disposed, the amount of light emitted in the direction of the user through the light scattering particles is increased, thereby improving the front transmittance.

[0021] In addition, a portion in which the amount of light is reduced can be prevented from being visually recognized by the light conversion portion region. That is, the overall brightness uniformity of the light path control member can be ensured, thereby the visibility of the user can be improved.

[0022] Further, in the optical path control member according to the embodiment, the specific gravity of the sealing material can be greater than the specific gravity of the dispersion liquid.

[0023] That is, the sealing material can be disposed on top of the dispersion liquid, the dispersion liquid can be caused to permeate into a predetermined region inside the housing portion, and then the substrate can be flipped upside down to cure the sealing material. Thus, a sealing layer that seals the dispersion liquid can be formed inside the housing portion.

[0024] Therefore, it is possible to solve the material restriction according to the specific gravity of the sealing material and the dispersion liquid, and thus to improve the sealing performance of the dispersion liquid by using a sealing material that has a high specific gravity but has high sealing performance. Further, by using a dispersion liquid that has a high specific gravity but has a high dielectric constant and a low viscosity, it is possible to improve the moving speed of the light-absorbing particles dispersed in the dispersion liquid.

[0025] Further, since the specific gravity of the sealing material is greater than the specific gravity of the dispersion liquid, the dispersion liquid can be disposed by moving upward from the inside of the housing portion, and the sealing material can be disposed by moving from the inside of the housing portion to the bottom.

[0026] Therefore, it is possible to prevent the dispersion liquid from overflowing in the direction of the partition wall portion below the housing portion, and thus to prevent the partition wall portion from being contaminated by the dispersion liquid.

[0027] That is, by causing the specific gravity of the sealing material to be greater than the specific gravity of the dispersion liquid, it is possible to prevent the dispersion liquid from overflowing to the outside.

[0028] Therefore, the optical path control member according to the embodiment can have improved driving characteristics and reliability. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a view that shows a perspective view of the optical path control member according to the embodiment.

[0030] Figure 2 and Figure 3 are views that show perspective views of the first substrate and the first electrode and the second substrate and the second electrode of the optical path control member according to the embodiment, respectively.

[0031] Figure 4 and Figure 5 are views that show cross-sectional views of the optical path control member according to the embodiment.

[0032] Figures 6 to 8 is a view that shows an enlarged view of the region A of Figure 5

[0033] Figures 9 to 12 is a view that shows another cross-sectional view of the optical path control member according to the embodiment.

[0034] Figures 13 to 15 is a view that shows Figure 5 ​is a view of another enlarged view of region A of FIG. 1.

[0035] Figure 16 and Figure 17 is a view of a cross-sectional view illustrating a light path control member according to another embodiment.

[0036] Figure 18 is a view of an enlarged view of region A of FIG. 1. Figure 16

[0037] Figure 19 is a cross-sectional view of a display device to which a light path control member according to an embodiment is applied.

[0038] Figure 20 and Figure 21 is a view for describing one embodiment of a display device to which a light path control member according to an embodiment is applied. DETAILED DESCRIPTION

[0039] Hereinafter, embodiments of the present application will be described in detail with reference to the accompanying drawings. However, the spirit and scope of the present application are not limited to a part of the described embodiments, and can be implemented in various other forms, and one or more elements of the embodiments can be selectively combined and replaced with each other within the spirit and scope of the present application.

[0040] In addition, unless explicitly defined and described otherwise, terms used in the embodiments of the present application, including technical terms and scientific terms, can be interpreted the same as the meaning that is commonly understood by one of ordinary skill in the art to which the present application pertains and can be interpreted as having the same meaning as the context of relevant technology.

[0041] In addition, the terms used in the embodiments of the present application are used to describe the embodiments, and are not intended to limit the present application. In the present specification, the singular form can also include the plural form unless explicitly defined and described otherwise in the context, and when described as "at least one of (or) a combination of" A, B, and C, it can include at least one of all combinations of the elements that can be combined in A, B, and C.

[0042] Further, in describing elements of the embodiments of the present application, terms such as first, second, A, B, (a), and (b) can be used. These terms are used only to distinguish the elements from other elements, and the terms do not limit the nature, order, or sequence of the elements.

[0043] In addition, when one element is described as being "connected", "coupled", or "bound" to another element, it can include not only a case where the element is directly "connected", "coupled", or "bound" to the other element, but also a case where the element is "connected", "coupled", or "bound" to the other element through another element.​

[0044] In addition, when described as being formed or disposed "on (above)" or "under (below)" each element, "on (above)" or "under (below)" can include not only a case where two elements are directly connected to each other, but also a case where one or more other elements are formed or disposed between the two elements.

[0045] In addition, when described as "on (above)" or "under (below)", it can include not only a direction based on an upper side of one element, but also a direction based on a lower side of one element.

[0046] Hereinafter, an optical path control member according to an embodiment will be described with reference to the accompanying drawings. The optical path control member described below relates to a switchable optical path control member driven in various modes according to movement of electrophoretic particles caused by voltage application.

[0047] Referring to Figures 1 to 3 The optical path control member according to an embodiment can include a first substrate 110, a second substrate 120, a first electrode 210, a second electrode 220, and a light conversion part 300.

[0048] The first substrate 110 can support the first electrode 210. The first substrate 110 can be rigid or flexible.

[0049] In addition, the first substrate 110 can be transparent. For example, the first substrate 110 can include a transparent substrate capable of transmitting light.

[0050] The first substrate 110 can include glass, plastic, or a flexible polymer film. For example, the flexible polymer film can 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), triacetyl cellulose (TAC) film, polyvinyl alcohol (PVA) film, polyimide (PI) film, and polystyrene (PS), which are merely examples, but embodiments are not limited thereto.

[0051] In addition, the first substrate 110 can be a flexible substrate having a flexible characteristic.

[0052] In addition, the first substrate 110 can be a flexible substrate having a flexible characteristic.

[0053] The first substrate 110 can have a thickness of 30 µm to 100 µm.

[0054] The first electrode 210 can be disposed on one surface of the first substrate 110. In detail, the first electrode 210 can be disposed on the upper surface of the first substrate 110. That is, the first electrode 210 can be disposed between the first substrate 110 and the second substrate 120.

[0055] The first electrode 210 can include a transparent conductive material. For example, the first electrode 210 can include a metal oxide, such as indium tin oxide, indium zinc oxide, copper oxide, tin oxide, zinc oxide, titanium oxide, or the like.

[0056] The first electrode 210 can be disposed on the first substrate 110 in a film shape. In detail, the light transmittance of the first electrode 210 can be about 80% or more. In detail, the first electrode 210 can be disposed on the entire surface of one surface of the first substrate 110. That is, the first electrode 210 can be disposed as a surface electrode on the first substrate 110.

[0057] The first electrode 210 can have a thickness of about 0.1 μm to about 0.5 μm.

[0058] Alternatively, the first electrode 210 can include various metals to achieve low resistance. For example, the first electrode 210 can include at least one metal of chromium (Cr), nickel (Ni), copper (Cu), aluminum (Al), silver (Ag), molybdenum (Mo), gold (Au), titanium (Ti), and an alloy of the above-described metals.

[0059] The first electrode 210 can be disposed on the entire surface of one surface of the first substrate 110. In detail, the first electrode 210 can be disposed on one surface of the first substrate 110 as a surface electrode. However, embodiments are not limited thereto, and the first electrode 210 can be formed of a plurality of pattern electrodes having a predetermined pattern.

[0060] For example, the first electrode 210 can include a plurality of conductive patterns. In detail, the first electrode 210 can include a plurality of mesh lines crossing each other and a plurality of mesh openings formed by the mesh lines.

[0061] Accordingly, even though the first electrode includes a metal, visibility can be improved because the first electrode is not visible from the outside. In addition, light transmittance is improved through the openings, and thus the brightness of the light path control member according to an embodiment can be improved.

[0062] The second substrate 120 can be disposed on the first substrate 110. In detail, the second substrate 120 can be disposed on the first electrode 210 on the first substrate 110.

[0063] The second substrate 120 can include a material capable of transmitting light. The second substrate 120 can include a transparent material. The second substrate 120 can include the same or similar material as the material of the first substrate 110 described above.

[0064] For example, the second substrate 120 can include glass, plastic, or a flexible polymer film. For example, the flexible polymer film can 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), triacetyl cellulose (TAC) film, polyvinyl alcohol (PVA) film, polyimide (PI) film, and polystyrene (PS), which are merely examples, but embodiments are not limited thereto.

[0065] In addition, the second substrate 120 can be a flexible substrate having a flexible characteristic.

[0066] Further, the second substrate 120 can be a curved or bent substrate. That is, the light path control member including the second substrate 120 can also be formed to have a flexible, curved, or bent characteristic. Accordingly, the light path control member according to the embodiments can be changed to various designs.

[0067] The second substrate 120 can have a thickness of 30 μm to 100 μm.

[0068] The second electrode 220 can be disposed on one surface of the second substrate 120. In detail, the second electrode 220 can be disposed on the lower surface of the second substrate 120. That is, the second electrode 220 can be disposed on the surface of the second substrate 120 facing the first substrate 110. That is, the second electrode 220 can be disposed to face the first electrode 210 on the first substrate 110. That is, the second electrode 220 can be disposed between the first electrode 210 and the second substrate 120.

[0069] The second electrode 220 can include a transparent conductive material. For example, the second electrode 220 can include a metal oxide, such as indium tin oxide, indium zinc oxide, copper oxide, tin oxide, zinc oxide, titanium oxide, or the like.

[0070] The second electrode 220 can be disposed on the first substrate 110 in a film shape. In addition, the light transmittance of the second electrode 220 can be about 80% or more. In detail, the second electrode 220 can be disposed on the entire surface of one surface of the second substrate 120. That is, the second electrode 220 can be disposed on the second substrate 120 as a surface electrode.

[0071] The second electrode 220 can have a thickness of about 0.1 μm to about 0.5 μm.

[0072] Alternatively, the second electrode 220 can include various metals to achieve low resistance. For example, the second electrode 220 can include at least one of chromium (Cr), nickel (Ni), copper (Cu), aluminum (Al), silver (Ag), molybdenum (Mo), gold (Au), titanium (Ti), and an alloy of the above-mentioned metals.

[0073] The second electrode 220 can be disposed on the entire surface of one surface of the second substrate 120. In detail, the second electrode 220 can be disposed as a surface electrode on one surface of the second substrate 120. However, embodiments are not limited thereto, and the second electrode 220 can be formed of a plurality of pattern electrodes having a predetermined pattern.

[0074] For example, the second electrode 220 can include a plurality of conductive patterns. In detail, the second electrode 220 can include a plurality of mesh lines crossing each other and a plurality of mesh openings formed by the mesh lines.

[0075] Accordingly, even though the second electrode 220 includes a metal, visibility can be improved because the second electrode 220 is not visible from the outside. In addition, light transmittance is improved through the openings, and thus brightness of the light path control member according to an embodiment can be improved.

[0076] The light conversion part 300 can be disposed between the first substrate 110 and the second substrate 120. In detail, the light conversion part 300 can be disposed between the first electrode 210 and the second electrode 220.

[0077] The light conversion part 300 can be attached to the first electrode 210 and the second electrode 220. For example, a buffer layer for improving adhesion to the light conversion part 300 is disposed on the first electrode 210, and the first electrode 210 and the light conversion part 300 can be formed through the buffer layer. In addition, an adhesive layer 400 for adhesion to the light conversion part 300 is disposed below the second electrode 220, and the second electrode 220 and the light conversion part 300 can be adhered to each other through the adhesive layer 400.

[0078] Referring to Figure 4 and Figure 5 The light conversion part 300 can include a partition wall part 310 and a housing part 320.

[0079] The partition wall part 310 can be defined as a partition wall part region that partitions the light transmission part. That is, the partition wall unit 310 is a partition wall part region that partitions a plurality of light transmission parts. In addition, the housing part 320 can be defined as a region that becomes a light blocking part and a light transmission part according to the application of a voltage.

[0080] That is, the accommodation portion 320 includes a plurality of accommodation portions. In detail, the accommodation portion 320 includes a plurality of unit accommodation units. In more detail, the accommodation portion 320 includes a plurality of unit accommodation units spaced apart from each other.

[0081] The partition wall portion 310 and the accommodation portion 320 can be alternately disposed with each other. The partition wall portion 310 and the accommodation portion 320 can be disposed to have different widths. For example, the width of the partition wall portion 310 can be greater than the width of the accommodation portion 320.

[0082] The partition wall portion 310 and the accommodation portion 320 can be alternately disposed. In detail, the partition wall portion 310 and the accommodation portion 320 can be alternately disposed. That is, each of the partition wall portions 310 can be disposed between the accommodation portions 320 adjacent to each other, and each of the accommodation portions 320 can be disposed between the partition wall portions 310 adjacent to each other.

[0083] The partition wall portion 310 can include a transparent material. The partition wall portion 310 can include a material that can transmit light.

[0084] The partition wall portion 310 can include a resin material. For example, the partition wall portion 310 can include a photocurable resin material. As an example, the partition wall portion 310 can include a UV resin or a transparent photoresist resin. Alternatively, the partition wall portion 310 can include a polyurethane resin or an acrylic resin.

[0085] The partition wall portion 310 can transmit light incident on any one of the first substrate 110 and the second substrate 120 toward the other substrate.

[0086] For example, in Figure 4 and Figure 5 , light can be emitted from the lower portion of the first substrate 110 and can be incident in a direction toward the second substrate 120. The partition wall portion 310 transmits the light, and the transmitted light can move to the upper portion of the second substrate 120.

[0087] The sealing portion 500 that seals the light path control member can be disposed on the side surface of the partition wall portion. Also, the side surface of the light conversion unit 300 can be sealed by the sealing portion.

[0088] The accommodation portion 320 can include the dispersion liquid 320a and the light absorbing particles 10 described above. In detail, the accommodation portion 320 is filled with the dispersion liquid 320a, and a plurality of light absorbing particles 10 can be dispersed in the dispersion liquid 320a.

[0089] The dispersion liquid 320a can be a material for dispersing the light absorbing particles 10. The dispersion liquid 320a can include a transparent material. The dispersion liquid 320a can include a non-polar solvent. In addition, the dispersion liquid 320a can include a material capable of transmitting light. For example, the dispersion liquid 320a can include at least one of a halogen hydrocarbon-based oil, a paraffin-based oil, and isopropyl alcohol.

[0090] The light absorbing particles 10 can be disposed to be dispersed in the dispersion liquid 320a. In detail, a plurality of light absorbing particles 10 can be disposed to be spaced apart from each other in the dispersion liquid 320a.

[0091] The light absorbing particles 10 can include a material capable of absorbing light. The light absorbing particles can have a color. In detail, the light absorbing particles 10 can include black particles capable of absorbing light. For example, the light absorbing particles can include carbon black particles.

[0092] Although not shown in the drawings, a sealing layer can be provided on the upper portion of the accommodation portion 320. In detail, a sealing layer for sealing the dispersion body from the outside can be provided on the upper portion of the accommodation portion 320.

[0093] The light transmittance of the accommodation portion 320 can be changed by the light absorbing particles 10. In detail, the accommodation portion 320 can change the light transmittance due to the light absorbing particles 10 and thus change into a light blocking portion and a light transmitting portion. That is, the accommodation portion 320 can change the transmittance of light passing through the accommodation portion 320 by the dispersion and aggregation of the light absorbing particles 10 in the dispersion liquid 320a provided therein.

[0094] For example, the light path control member according to the embodiment can change from the first mode to the second mode or from the second mode to the first mode by the voltage applied to the first electrode 210 and the second electrode 220.

[0095] In detail, in the light path control member according to the embodiment, the accommodation portion 320 becomes a light blocking portion in the first mode, and light of a specific angle can be blocked by the accommodation portion 320. That is, the angle of view of the user observed from the outside can be narrowed.

[0096] In addition, in the light path control member according to the embodiment, the accommodation portion 320 becomes a light transmitting portion in the second mode, and in the light path control member according to the embodiment, light can be transmitted through both the partition wall unit 310 and the accommodation portion 320. That is, the angle of view of the user observed from the outside can be widened.

[0097] The switching from the first mode to the second mode, i.e., the conversion of the housing portion 320 from the light blocking portion to the light transmitting portion, can be achieved by the movement of the light absorbing particles 10 of the housing portion 320. That is, the light absorbing particles 10 have a charge on the surface, and can move in the direction of the first electrode or the second electrode according to the characteristics of the charge by the applied voltage. That is, the light absorbing particles 10 can be electrophoretic particles.

[0098] In detail, the housing portion 320 can be electrically connected to the first electrode 210 and the second electrode 220.

[0099] In this case, when no voltage is applied from the outside to the light path control member, the light absorbing particles 10 of the housing portion 320 are uniformly dispersed in the dispersion liquid 320a, and light can be blocked by the light conversion particles in the housing portion 320. Therefore, in the first mode, the housing portion 320 can be driven as a light blocking portion.

[0100] Alternatively, when a voltage is applied from the outside to the light path control member, the light absorbing particles 10 can move. For example, the light absorbing particles 10 can move toward one end or the other end of the housing portion 320 by the voltage transmitted through the first electrode 210 and the second electrode 220. That is, the light absorbing particles 10 can move from the housing portion 320 toward the first electrode or the second electrode.

[0101] In detail, when a voltage is applied to the first electrode 210 and / or the second electrode 220, an electric field is formed between the first electrode 210 and the second electrode 220, and the charged carbon black, i.e., the light absorbing particles, can move toward the anode of the first electrode 210 and the second electrode 220 using the dispersion liquid 320a as a medium.

[0102] That is, when no voltage is applied to the first electrode 210 and / or the second electrode 220, as shown in FIG. 2A, the light absorbing particles 10 can be uniformly dispersed in the dispersion liquid 320a to drive the housing portion 320 as a light blocking portion. Figure 4

[0103] Further, when a voltage is applied to the first electrode 210 and / or the second electrode 220, as shown in FIG. 2B, the light absorbing particles 10 can move toward the first electrode 210 in the dispersion liquid 320a. That is, the light absorbing particles 10 move in one direction, and the housing portion 320 can be driven as a light transmitting portion. Figure 5

[0104] Therefore, according to the surrounding environment of the user, the light path control member according to the embodiment can be driven in two modes. That is, when the user needs light transmission only at a specific viewing angle, the housing portion is driven as a light blocking portion, or in an environment where the user needs high brightness, a voltage can be applied to drive the housing portion as a light transmitting portion. ​​

[0105] Therefore, since the light path control member according to the present embodiment can be implemented in two modes according to the user's needs, the light path control member can be applied regardless of the user's environment.

[0106] Meanwhile, in the second mode in which the light-absorbing particles 10 of the accommodation portion 320 move toward the electrodes and the accommodation portion 320 is driven as a light-transmitting portion, the emitted light can pass through the accommodation portion.

[0107] In this case, the light is still blocked in the region in which the light-absorbing particles 10 of the accommodation portion 320 are gathered, and thus the region through which the light is transmitted can decrease as the gathered region increases.

[0108] Therefore, the light path control member according to the present embodiment can increase the light transmission area of the accommodation portion in the second mode by controlling the particle diameter of the light-absorbing particles.

[0109] In detail, referring to Figure 6 , the light-absorbing particles 10 can include first particles 11 and second particles 12.

[0110] The first particles 11 and the second particles 12 can include the same material. For example, the first particles 11 and the second particles 12 can include carbon black particles.

[0111] The first particles 11 and the second particles 12 can be formed in a spherical shape. In addition, the first particles 11 and the second particles 12 can be formed to have a particle diameter of a nanometer unit. In detail, the first particles 11 and the second particles 12 can be formed to have a particle diameter of 500 nm to 700 nm.

[0112] When the particle diameter of the first particles 11 and the second particles 12 is less than 500 nm, the first particles 11 and the second particles 12 are gathered within the dispersion liquid 320a, and thus the dispersibility can decrease.

[0113] In addition, when the particle diameter of the first particles 11 and the second particles 12 exceeds 700 nm, the weight of the first particles 11 and the second particles 12 increases, and thus the first particles 11 and the second particles 12 can be deposited at the lower portion of the accommodation portion.

[0114] In addition, the first particles 11 and the second particles 12 can be charged with the same polarity of charges. That is, the surfaces of the first particles 11 and the second particles 12 can be charged with (+) or (-) polarity of charges. Therefore, when a voltage is applied to the first electrode and / or the second electrode, the first particles 11 and the second particles 12 can move in the same direction to each other.

[0115] In addition, the first particles 11 and the second particles 12 can have the same specific gravity. Specifically, the specific gravity of the first particles 11 and the second particles 12 can be 2 or less.

[0116] The first particles 11 and the second particles 12 can have different sizes. In detail, the particle diameter of the first particles 11 and the particle diameter of the second particles 12 can be different from each other.

[0117] That is, light-absorbing particles having different sizes can be disposed together in each accommodation portion of the light path control member. That is, by disposing light-absorbing particles having different sizes together inside the accommodation portion 320, the same light-absorbing effect can be achieved. In addition, when power is applied and the light-absorbing particles are gathered in one area, the packing density of the gathered light-absorbing particles can be improved.

[0118] Reference Figure 6 The particle diameter of the first particles 11 can be greater than the particle diameter of the second particles 12. The ratio of the particle diameter of the second particles 12 to the particle diameter of the first particles 11 can be 1:3 or more. In detail, the ratio of the particle diameter of the second particles 12 to the particle diameter of the first particles 11 can be 1:3 to 1:10.

[0119] When the ratio of the particle diameter of the second particles 12 to the particle diameter of the first particles 11 is less than 1:3, since the difference in the particle diameter of the first particles 11 and the second particles 12 is not large, the packing density of the light-absorbing particles can be reduced. Therefore, the transmission effect can not be large.

[0120] In addition, when the ratio of the particle diameter of the second particles 12 to the particle diameter of the first particles 11 exceeds 1:10, either particle becomes too large to reduce the packing density of the light-absorbing particles, or either particle can become too small to manufacture.

[0121] In addition, the contents of the first particles 11 and the second particles 12 can be different. In detail, the total volume of the first particles 11 and the second particles 12 disposed inside any one of the accommodation portions can be different from each other. In detail, in at least one of the plurality of unit accommodation units, the total volume of the first particles can be greater than the total volume of the second particles. That is, in all of the plurality of unit accommodation units, the total volume of the first particles is greater than the total volume of the second particles, or in some of the plurality of unit accommodation units, the total volume of the first particles is greater than the total volume of the second particles.

[0122] For example, in at least one of the plurality of unit accommodation units, the second particles 12 having a relatively small particle size can be included in an amount of 5% or more by volume based on the total volume of the light-absorbing particles. In detail, the second particles 12 can be included in an amount of 5% to 20% by volume based on the total volume of the light-absorbing particles.

[0123] When the content of the second particles 12 is less than 5% by volume, the transmittance improvement effect is small due to the increase in the bulk density of the first particles 11. When the content of the second particles 12 exceeds 20% by volume, the light absorption effect can be reduced, and thus the viewing angle control effect can be reduced.

[0124] Figure 7 is a view for explaining an example in which only light-absorbing particles having the same particle diameter are disposed inside the accommodation portion 320, Figure 8 is a view for explaining an example in which light-absorbing particles of which the first particles 11 and the second particles 12 having different particle diameters are disposed inside the accommodation portion 320.

[0125] Referring to Figure 7 and 8 , the second particles 12 can improve the transmittance of the light path control member.

[0126] In detail, referring to Figure 7 , when only light-absorbing particles 10 having the same particle diameter are disposed inside the accommodation portion 320, in the second mode, the bulk density of the light-absorbing particles gathered in the direction of the first electrode 210 can depend on the particle diameter of the light-absorbing particles 10.

[0127] For example, referring to Figure 7 , the light-absorbing particles 10 inside the accommodation portion have a first height h1 due to the bulk density of the light-absorbing particles gathered in the direction of the first electrode 210 in the second mode.

[0128] In addition, referring to Figure 8 , when the light-absorbing particles 10 including the first particles 11 and the second particles 12 having different particle diameters are disposed inside the accommodation portion 320, in the second mode, the bulk density of the light-absorbing particles gathered in the direction of the first electrode 210 can depend on the volume percentage and the particle diameter of the first particles 11 and the second particles 12.

[0129] For example, referring to Figure 8 , in the second mode, the light-absorbing particles 10 can be disposed at a second height h2 inside the accommodation portion due to the bulk density of the light-absorbing particles gathered in the direction of the first electrode 210.

[0130] At this time, in the case of the light-absorbing particles 10 including the first particles 11 and the second particles 12 having different particle diameters, they can be gathered and disposed at a low height inside the accommodation portion compared to the light-absorbing particles 10 having the same particle diameter.

[0131] That is, in the case of the light absorbing particles 10 including the first particles 11 and the second particles 12 having different particle diameters, since they have an increased packing density compared to the light absorbing particles 10 having the same particle diameter, they can be gathered and disposed at a low height within the accommodation portion.

[0132] Accordingly, the gathering height of the light absorbing particles can be reduced, thereby increasing the light transmission area of the accommodation portion in the second mode. Accordingly, by increasing the light transmission area in the second mode, the front luminance can be improved, thereby improving the visibility of the user.

[0133] Meanwhile, the accommodation portion 320 can be formed in various shapes.

[0134] Reference Figure 4 and Figure 5 , the accommodation portion 320 extends from one end of the accommodation portion 310 to the other end, and the width of the accommodation portion 320 can vary.

[0135] For example, with reference to Figure 4 and Figure 5 , the accommodation portion 320 can be formed in a trapezoidal shape. In detail, the accommodation portion 320 can be formed such that the width of the accommodation portion 320 widens while extending from the first electrode 210 to the second electrode 220.

[0136] That is, the width of the accommodation portion 320 can narrow while extending in the opposite direction from the observation surface of the user. In addition, when a voltage is applied to the light conversion portion, the light absorbing particles of the accommodation portion 320 can move in the direction in which the width of the accommodation portion narrows.

[0137] That is, the width of the accommodation portion 320 can increase while extending from the light incident portion to which light is incident to the light output portion from which light is emitted.

[0138] Accordingly, since the light absorbing particles move in the direction opposite to the observation surface rather than the observation surface, it is possible to prevent the blocking of light emitted in the direction of the observation surface, thereby improving the luminance of the light path control member.

[0139] In addition, since the light absorbing particles move from a wide area to a narrow area, the light absorbing particles can easily move.

[0140] In addition, since the light absorbing particles move to the narrow area of the accommodation portion, the amount of light transmitted in the direction of the observation surface of the user increases, thereby improving the front luminance.

[0141] Alternatively, on the contrary, the accommodation portion 320 can be formed such that the width of the accommodation portion 320 narrows while extending from the first electrode 210 to the second electrode 220.

[0142] That is, the width of the accommodation portion 320 can widen while extending from the light incident portion to which light is incident to the light output portion from which light is emitted.

[0143] That is, the width of the accommodation portion 320 can narrow while extending from the light incident portion to which light is incident to the light output portion from which light is emitted.

[0144] Accordingly, the contact area between the first electrode and one surface of the accommodation portion through which the light-absorbing particles move increases, and thus the moving speed of the light-absorbing particles, that is, the driving speed can increase.

[0145] Further, the accommodation portion 320 can be disposed to be spaced apart from the first electrode 210 or the second electrode 220.

[0146] For example, referring to Figure 4 and 5 , the accommodation portion 320 can be spaced apart from the first electrode 210 and can be in indirect contact with the second electrode 220.

[0147] The same or similar material as the partition wall portion 310 can be disposed in a region in which the accommodation portion 320 and the first electrode 220 are spaced apart from each other.

[0148] Alternatively, embodiments are not limited thereto, and as shown in Figure 9 and Figure 10 , both ends of the accommodation portion can be disposed to be in direct or indirect contact with the first electrode 210 and the second electrode 220, respectively.

[0149] Accordingly, since the accommodation portion 320 is in direct contact with the first electrode 210 and the second electrode 220, a voltage is easily transmitted in the direction of the accommodation portion 320 without being affected by resistance, and thus driving characteristics can be improved.

[0150] Further, the accommodation portion 320 can be disposed to have a constant inclination angle θ. In detail, referring to Figure 11 and Figure 12 , the accommodation portion 320 can be disposed to have an inclination angle θ of greater than 0° to less than 90° with respect to the first electrode 210. In detail, the accommodation portion 320 can extend upward while having an inclination angle θ of greater than 0° to less than 90° with respect to one surface of the first electrode 210.

[0151] Accordingly, when the light path member is used together with the display panel, moiré caused by the overlap between the pattern of the display panel and the accommodation portion 320 of the light path control member can be prevented, and thus user visibility can be improved.

[0152] Hereinafter, a light path control member according to another embodiment will be described with reference to Figures 13 to 15 .

[0153] Figures 13 to 15 is a view showing another enlarged view of the area A of Figure 5 .

[0154] Referring to Figure 13 , the light absorbing particles 10 can include first particles 11 and second particles 12.

[0155] The first particles 11 and the second particles 12 can be disposed together in the dispersion liquid 320a. In detail, the first particles 11 and the second particles 12 can be spaced apart from each other and dispersed in the dispersion liquid 320a.

[0156] The first particles 11 and the second particles 12 can have different reflectances. In detail, the reflectance of the first particles 11 can be less than the reflectance of the second particles 12. For example, the reflectance of the first particles 11 can be about 0.1% or less, and the reflectance of the second particles 12 can be about 50% to about 90%.

[0157] That is, light incident to the first particles 11 is hardly reflected, the first particles 11 can absorb it, and light incident to the second particles 12 can be reflected and diffused about 50% to about 90%.

[0158] In detail, the first particles 11 can absorb light incident into the accommodation portion 320. That is, the accommodation portion 320 can become a light transmission portion and a light blocking portion by the first particles 11. That is, the first particles 11 can be light absorbing particles.

[0159] The first particles 11 can be formed in a spherical shape. In addition, the first particles 11 can be formed to have a particle diameter of a nanometer unit. In detail, the first particles 11 can be formed to have a particle diameter of 500 nm to 700 nm.

[0160] When the particle diameter of the first particles 11 is less than 500 nm, dispersibility can be decreased due to aggregation of the first particles 11 within the dispersion liquid 320a.

[0161] In addition, when the particle diameter of the first particles 11 exceeds 700 nm, the weight of the first particles 11 can increase, and thus the first particles 11 can be deposited into a lower portion of the accommodation portion.

[0162] The first particles 11 can have a color. In detail, the first particles 11 can include black particles. For example, the first particles 11 can include carbon black.

[0163] The second particles 12 can partially absorb and partially reflect light incident into the accommodation portion. That is, the second particles 12 can have both reflection and absorption characteristics. That is, the second particles 12 can be light scattering particles.

[0164] The second particles 12 can be formed in a spherical shape. Also, the second particles 12 can be formed to have a particle diameter of a nanometer unit. In detail, the second particles 12 can be formed to have a particle diameter of 500 nm to 700 nm. The first particles 11 and the second particles 12 can have the same or similar particle diameters in a particle diameter size range.

[0165] When the particle diameter of the second particles 12 is less than 500 nm, the second particles 12 can be aggregated in the dispersion liquid 320a, and thus the dispersibility can be decreased.

[0166] Also, when the particle diameter of the second particles 12 exceeds 700 nm, the weight of the second particles 12 can be increased, and thus the second particles 12 can be deposited in a lower portion of the accommodation portion.

[0167] The second particles 12 can have a color. In detail, the second particles 12 can include black particles.

[0168] The second particles 12 can include a metal. In detail, the second particles 12 can include a metal oxide. For example, the second particles 12 can include at least one of titanium dioxide (TiO2), zirconium oxide (ZrO2), indium oxide (In2O3), tin oxide (SnO2), and aluminum oxide (Al2O3).

[0169] In addition, the first particles 11 and the second particles 12 can be charged with the same polarity of charges. That is, the surfaces of the first particles 11 and the second particles 12 can be charged with (+) or (-) polarity of charges. Thus, when a voltage is applied to the first electrode and / or the second electrode, the first particles 11 and the second particles 12 can move in the same direction.

[0170] Also, the first particles 11 and the second particles 12 can have different specific gravities. In detail, the specific gravity of the first particles 11 can be less than the specific gravity of the second particles 12. For example, the specific gravity of the first particles 11 can be 2 or less, and the specific gravity of the second particles 12 can be 3 to 8.

[0171] A dispersant for facilitating dispersion of the first particles 11 and the second particles 12 can be further included in the accommodation portion. In detail, in order to prevent phase separation due to a difference in specific gravity between the first particles 11 and the second particles 12 including different materials, a dispersant for causing dispersion of the first particles 11 and the second particles 12 can be further included in the accommodation portion.

[0172] Figure 14 is a view for explaining an example in which only the first particles 11 are disposed in the accommodation portion 320, Figure 15 is a view for explaining an example in which the first particles 11 and the second particles 12 are disposed together in the accommodation portion 320.

[0173] ReferenceFigure 14 and 15 The second particles 12 can improve the front surface brightness of the light path control member.

[0174] In detail, referring to Figure 14 When only the first particles 11, that is, only the light absorbing particles are disposed in the accommodation portion 320, most of the light incident in the direction of the accommodation portion can be blocked by the first particles gathered. That is, since the light incident in the direction of the accommodation portion is blocked and cannot be emitted in the direction of the user, the front surface brightness of the light path control member can be reduced. In addition, since the light incident in the direction of the accommodation portion is blocked, the brightness in a specific area becomes less than the brightness in other areas, and the brightness uniformity of the light path control member can be reduced.

[0175] However, referring to Figure 15 When the first particles 11 and the second particles 12 are disposed together in the accommodation portion 320, the amount of light emitted toward the user through the second particles 12 can be increased.

[0176] In detail, referring to Figure 15 The light incident to the second particles 12 through the second particles 12 gathered together with the first particles 11 can be scattered and refracted. Therefore, the amount of light emitted in the direction of the user through the accommodation portion can be increased by reflection and refraction of the light passing through the second particles 12.

[0177] Therefore, the front surface brightness of the light path control member can be improved, and the brightness uniformity of the light path control member can be improved.

[0178] Meanwhile, the first particles 11 and the second particles 12 can be contained in different weight percentages. In detail, the first particles 11 included in each accommodation portion can be contained more than the second particles 12.

[0179] In detail, the first particles 11 within each accommodation portion can be contained in an amount of 95 wt% to 99 wt% with respect to the total particles. In addition, the second particles 12 can be contained in an amount of 1 wt% to 5 wt% based on the total particles.

[0180] When the content of the second particles 12 is less than about 1 wt% with respect to the total particles, since the light scattering effect of the second particles is small, it is difficult to improve the front surface transmittance. In addition, when the content of the second particles 12 is greater than about 5 wt% with respect to the total particles, since the amount of the first particles is reduced, the light absorption rate in the accommodation portion can be reduced, and the change in improvement of the front surface transmittance can not be significant.

[0181] Hereinafter, the present application will be described in more detail by the transmittance of the light path control member according to the examples and the comparative examples. These examples are presented only as examples to explain the present application in more detail. Therefore, the present application is not limited to these examples.

[0182] Example 1

[0183] A first electrode and a second electrode including indium tin oxide (ITO) are formed on one surface of a first substrate and a second substrate including polyethylene terephthalate (PET), respectively.

[0184] Then, a UV resin is disposed on the first substrate and is imprint-pressed by a mold to form a housing portion.

[0185] Then, a light conversion portion is formed by filling the housing portion with paraffin oil in which carbon black particles and titanium dioxide particles are dispersed.

[0186] At this time, the content of the titanium dioxide particles is 5 wt% with respect to the total particles.

[0187] Next, after the first substrate, the second substrate, and the light conversion portion are attached to prepare a light path control member, when a voltage is applied, the front surface transmittance of the light path control member is measured.

[0188] Example 2

[0189] After the light path control member is manufactured in the same manner as in Example 1 except that paraffin oil in which carbon black particles and zirconium oxide particles are dispersed is filled in the housing portion, when a voltage is applied, the front surface transmittance of the light path control member is measured.

[0190] At this time, the content of the zirconium oxide particles is 5 wt% with respect to the total particles.

[0191] Example 3

[0192] After the light path control member is manufactured in the same manner as in Example 1 except that paraffin oil in which carbon black particles and indium oxide particles are dispersed is filled in the housing portion, when a voltage is applied, the front surface transmittance of the light path control member is measured.

[0193] At this time, the content of the indium oxide particles is 5 wt% with respect to the total particles.

[0194] Example 4

[0195] After the light path control member is manufactured in the same manner as in Example 1 except that paraffin oil in which carbon black particles and tin oxide particles are dispersed is filled in the housing portion, when a voltage is applied, the front surface transmittance of the light path control member is measured.

[0196] At this time, the content of the tin oxide particles is 5 wt% with respect to the total particles.

[0197] Example 5

[0198] In addition to filling the paraffin oil in which the carbon black particles and the alumina particles are dispersed in the housing portion, after the light path control member was manufactured in the same manner as in Example 1, the front surface transmittance of the light path control member was measured when a voltage was applied.

[0199] At this time, the content of the alumina particles was 5 wt% with respect to the total particles.

[0200] Comparative Example 1

[0201] In addition to filling the paraffin oil in which only the carbon black particles were dispersed in the housing portion, after the light path control member was manufactured in the same manner as in Example 1, the front surface transmittance of the light path control member was measured when a voltage was applied.

[0202] Comparative Example 2

[0203] In addition to the content of the titanium dioxide particles being 7 wt% with respect to the total particles, after the light path control member was manufactured in the same manner as in Example 1, the front surface transmittance of the light path control member was measured when a voltage was applied.

[0204] Comparative Example 3

[0205] In addition to the content of the zirconium dioxide particles being 7 wt% with respect to the total particles, after the light path control member was manufactured in the same manner as in Example 2, the front surface transmittance of the light path control member was measured when a voltage was applied.

[0206] Comparative Example 4

[0207] In addition to the content of the indium oxide particles being 7 wt% with respect to the total particles, after the light path control member was manufactured in the same manner as in Example 3, the front surface transmittance of the light path control member was measured when a voltage was applied.

[0208] Comparative Example 5

[0209] In addition to the content of the tin oxide particles being 7 wt% with respect to the total particles, after the light path control member was manufactured in the same manner as in Example 4, the front surface transmittance of the light path control member was measured when a voltage was applied.

[0210] Comparative Example 6

[0211] In addition to the content of the alumina particles being 7 wt% with respect to the total particles, after the light path control member was manufactured in the same manner as in Example 6, the front surface transmittance of the light path control member was measured when a voltage was applied.

[0212] [Table 1]

[0213]

[0214] Referring to Table 1, the front surface transmittance of the light path control member according to Embodiments 1 to 5 is greater than that of the light path control member according to Comparative Example.

[0215] That is, when a voltage is applied to the light path control member according to Embodiments 1 to 5 to drive the accommodation portion as the light-transmissive portion, the amount of light moving in the front surface direction is increased by the metal oxide particles that reflect and diffuse light.

[0216] In addition, when the metal oxide particles exceed 5 wt% with respect to the total particles, the effect of improving the front surface transmittance can be reduced due to an increase in the side surface transmittance rather than the front surface transmittance.

[0217] Hereinafter, a light path control member according to another embodiment will be described with reference to Figures 16 to 18 A light path control member according to another embodiment will be described.

[0218] Referring to Figures 16 to 18 , the adhesive layer 400 is disposed between the second substrate 120 and the light conversion portion 300, and the second substrate 120 and the light conversion portion 300 can be adhered to each other by the adhesive layer 400.

[0219] The adhesive layer 400 can have a dielectric constant. In addition, the adhesive layer 400 can have polarity. For example, the adhesive layer 400 can include an optically clear adhesive (OCA).

[0220] The adhesive layer 400 can be disposed on the first substrate 110 and have a different thickness for each region.

[0221] In detail, referring to Figure 18 , the first substrate 110 includes a first region 1A corresponding to the partition wall portion 310 and a second region 2A corresponding to the accommodation portion 320, and the adhesive layer 400 can be disposed to have a different thickness in the first region 1A and the second region 2A.

[0222] In detail, the adhesive layer thickness T2 of the second region can be greater than the adhesive layer thickness T1 of the first region. That is, the adhesive layer of the second region is disposed to partially fill the inside of the accommodation portion 320, and it can be disposed to be thicker than the adhesive layer in the first region by the same thickness as the adhesive layer disposed in the accommodation portion 320.

[0223] Since the adhesive layer 400 is disposed on the first substrate 110 with a different thickness for each region, the adhesive surface of the adhesive layer can be formed in a concave-convex shape. Therefore, after the first substrate 110 and the light conversion portion 300 are attached by the adhesive layer 400, the adhesion of the light conversion portion 300 can be improved by the concave-convex shape.

[0224] Accordingly, the light conversion part 300 can be prevented from being removed from the substrate, thereby improving reliability of the light path control member.

[0225] Meanwhile, the sealing layer 600 can be provided in the accommodation part 320. In detail, the sealing layer 600 can be provided in the accommodation part 320. The sealing layer 600 can be provided on the adhesive layer 400 provided inside the accommodation part. That is, the adhesive layer 400, the sealing layer 600, and the dispersion liquid 320a in which the light absorbing particles are dispersed under the second substrate 120 can be sequentially provided in the accommodation part 320.

[0226] The sealing layer 600 prevents the dispersion liquid 320a from being changed due to exposure of the dispersion liquid 320a to the outside, and can prevent degradation of the light absorbing particles 10 inside the dispersion liquid 320a.

[0227] The sealing layer 600 can be provided only in a specific area. That is, the sealing layer 600 can be provided only inside the accommodation part 320, and can not be provided on an area corresponding to the partition wall part 310.

[0228] Accordingly, the adhesive layer 400 can be in direct contact with the partition wall part 310 of the light conversion part, thereby improving adhesion properties of the adhesive layer 400.

[0229] Further, direct contact between the adhesive layer 400 and the dispersion liquid 320a can be prevented by the sealing layer 600.

[0230] In the case where the adhesive layer 400 includes an optically transparent adhesive, when the adhesive layer has dielectric properties, it can have polarity. Accordingly, when the dispersion liquid having polarity is in direct contact with the adhesive layer 400, the performance of the adhesive layer at the interface can be reduced.

[0231] That is, as the adhesive layer 400 and the dispersion liquid 320a are in direct contact with each other, the adhesion of the adhesive layer 400 and the polarity of the dispersion liquid 320a can be reduced.

[0232] Accordingly, by providing the sealing layer 600 between the adhesive layer 400 and the dispersion liquid 320a, direct contact between the adhesive layer 400 and the dispersion liquid 320a can be prevented. That is, the sealing layer having no polarity can be in direct contact with the adhesive layer and the dispersion liquid between the adhesive layer and the dispersion liquid.

[0233] Accordingly, by maintaining the adhesion of the adhesive layer, the adhesion of the first substrate and the light conversion part can be improved, and by preventing reduction of the polarity of the dispersion liquid, reduction of the moving speed of the light absorbing particles in the dispersion liquid can be prevented.

[0234] The sealing layer 600 can be formed by curing the sealing material. In this case, the specific gravity of the sealing layer 600 can be different from the specific gravity of the dispersion liquid 320a. In detail, the specific gravity of the sealing layer 600 can be greater than the specific gravity of the dispersion liquid 320a.

[0235] For example, the specific gravity of the dispersion liquid 320a can be 0.7 to 0.9. Also, the specific gravity of the sealing material forming the sealing layer can exceed 0.9 and be up to 2.2. In detail, the sealing material can include a polymer material having a specific gravity exceeding 0.9 and being up to 2.2. For example, the sealing material can include a material such as polyurethane acrylate or epoxy resin having a specific gravity exceeding 0.9 and being up to 2.2.

[0236] Conventionally, a photocurable resin layer is coated on a substrate, a concave-shaped accommodation portion is formed on the resin layer through an imprint process, and then the accommodation portion is filled with a dispersion liquid in which light-absorbing particles are dispersed. Then, a sealing material is coated on the dispersion liquid, and then the sealing material is cured to form a sealing layer.

[0237] In this case, when the specific gravity of the sealing material is higher than the specific gravity of the dispersion liquid, there is a problem that a sealing material having a specific gravity lower than the dispersion liquid should be used due to the problem of the sealing material penetrating into the lower portion of the dispersion liquid.

[0238] That is, there is a limitation in the selection of materials according to the specific gravity of the sealing material and the dispersion liquid due to the process sequence of the sealing material and the dispersion liquid.

[0239] However, in the light path control member according to the embodiment, the specific gravity of the sealing material can be higher than the specific gravity of the dispersion liquid. Therefore, since the sealing material having a higher specific gravity than the dispersion liquid can be used, the selection range of the sealing material can be expanded. Also, since a dispersion liquid having high dielectric properties and low viscosity can be applied because the dispersion liquid uses a material having a large specific gravity, the moving speed of the light-absorbing particles in the dispersion liquid can be increased.

[0240] In addition, since the specific gravity of the sealing material is greater than the specific gravity of the dispersion liquid, the dispersion liquid can be disposed by moving from the inside of the accommodation portion to the upper portion, and the sealing material can be disposed by moving downward in the accommodation portion.

[0241] Therefore, it is possible to prevent the partition wall portion from being contaminated by the dispersion liquid overflowing in the direction of the partition wall portion below the accommodation portion.

[0242] That is, by making the specific gravity of the sealing material greater than the specific gravity of the dispersion liquid, it is possible to prevent the dispersion liquid from overflowing to the outside.

[0243] Hereinafter, a display device and a display apparatus to which the light path control member according to the embodiment is applied will be described with reference to Figures 19 to 21 ​

[0244] Reference Figure 19 According to the embodiment, the optical path control component 1000 can be disposed on the display panel 2000.

[0245] The display panel 2000 and the optical path control component 1000 can be configured to be attached to each other. For example, the display panel 2000 and the optical path control component 1000 can be attached to each other via an adhesive layer 1500. The adhesive layer 1500 can be transparent. For example, the adhesive layer 1500 can include an adhesive or an adhesive layer containing an optically transparent adhesive material.

[0246] The adhesive layer 1500 may include a release film. Specifically, when attaching the optical path control component and the display panel, the optical path control component and the display panel can be attached after removing the release film.

[0247] The display panel 2000 may include a first substrate 2100 and a second substrate 2200. When the display panel 2000 is a liquid crystal display panel, a light path control member may be formed below the liquid crystal panel. That is, when the user viewing side of the liquid crystal panel is defined as the upper part of the liquid crystal panel, a light path control member may be provided below the liquid crystal panel. The display panel 2000 may be formed as a structure in which a first substrate 2100 including thin-film transistors (TFTs) and pixel electrodes is attached to a second substrate 2200 including a color filter layer through a liquid crystal layer interposed between them.

[0248] Alternatively, the display panel 2000 can be a liquid crystal display panel with a color filter on transistor (COT) structure. In this COT structure, thin-film transistors, a color filter, and a black matrix are formed on a first substrate 2100, a second substrate 2200 is bonded to the first substrate 2100, and a liquid crystal layer is disposed between the first substrate 2100 and the second substrate 2200. That is, thin-film transistors can be formed on the first substrate 2100, a protective film can be formed on the thin-film transistors, and a color filter layer can be formed on the protective film. Additionally, pixel electrodes that contact the thin-film transistors can be formed on the first substrate 2100. In this respect, to improve the aperture ratio and simplify the masking process, the black matrix can be omitted, and a common electrode can be formed to serve as the black matrix.

[0249] Furthermore, when the display panel 2000 is a liquid crystal display panel, the display device may further include a backlight unit that provides light from the rear surface of the display panel 2000. The backlight unit may be disposed below the light path control member.

[0250] That is, such as Figure 18 As shown, the optical path control component can be located below the LCD panel.

[0251] Alternatively, when the display panel 2000 is an organic light emitting display panel, the light path control member can be formed on the organic light emitting display panel. That is, when a surface observed by a user of the organic light emitting display panel is defined as an upper portion of the organic light emitting display panel, the light path control member can be disposed on the organic light emitting display panel. The display panel 2000 can include a self-emitting element that does not require a separate light source. In the display panel 2000, a thin film transistor can be formed on the first substrate 2100, and an organic light emitting element in contact with the thin film transistor can be formed. The organic light emitting element can include an anode, a cathode, and an organic light emitting layer formed between the anode and the cathode. Further, a second substrate 2200 configured to function as an encapsulation substrate for encapsulation can be further included on the organic light emitting element.

[0252] Further, although not shown in the drawings, a polarizing plate can be further disposed between the light path control member 1000 and the display panel 2000. The polarizing plate can be a linear polarizing plate or an external light reflection prevention polarizing plate. For example, when the display panel 2000 is a liquid crystal display panel, the polarizing plate can be a linear polarizing plate. Further, when the display panel 2000 is an organic light emitting display panel, the polarizing plate can be an external light reflection prevention polarizing plate.

[0253] In addition, an additional functional layer 1300, such as an anti-reflection layer, an anti-glare, etc., can be further disposed on the light path control member 1000. Specifically, the functional layer 1300 can be adhered to one surface of the substrate of the light path control member. Although not shown in the drawings, the functional layer 1300 can be adhered to the first substrate 110 of the light path control member by an adhesive layer. In addition, a release film for protecting the functional layer can be further disposed on the functional layer 1300.

[0254] Further, a touch panel can be further disposed between the display panel and the light path control member.

[0255] Although the light path control member is shown as being disposed on an upper portion of the display panel in the drawings, embodiments are not limited thereto, and the light path control member can be disposed at various positions, such as a position where light can be adjusted, i.e., a lower portion of the display panel, can be disposed between the second substrate and the first substrate of the display panel, etc.

[0256] Referring to Figure 20 and Figure 21 , the light path control member according to embodiments can be applied to a vehicle.

[0257] Referring to Figure 20 and Figure 21 , the light path control member according to embodiments can be applied to a display device displaying a display.

[0258] For example, when as Figure 20As shown, when no power is applied to the light path control member, the housing unit functions as a light blocking portion, so that the display device is driven in a light blocking mode, and when power is applied to the light path control member as shown, the housing unit functions as a light transmitting portion, so that the display device can be driven in an open mode. Figure 21 As shown, when no power is applied to the light path control member, the housing unit functions as a light blocking portion, so that the display device is driven in a light blocking mode, and when power is applied to the light path control member as shown, the housing unit functions as a light transmitting portion, so that the display device can be driven in an open mode.

[0259] Therefore, the user can easily drive the display device in a privacy mode or a normal mode according to the application of power.

[0260] In addition, although not shown in the drawings, a display device to which the light path control member according to the embodiment is applied can also be applied to a vehicle interior.

[0261] For example, a display device including the light path control member according to the embodiment can display video confirmation information of a vehicle and a moving route of the vehicle. The display device can be disposed between a driver seat and a passenger seat of the vehicle.

[0262] In addition, the light path control member according to the embodiment can be applied to an instrument panel that displays a speed, an engine, an alarm signal, etc. of a vehicle.

[0263] Further, the light path control member according to the embodiment can be applied to a front glass (FG) or a left and right window glass of a vehicle.

[0264] The features, structures, effects, etc. described in the above-described embodiments are included in at least one embodiment of the present application, but are not limited to only one embodiment. In addition, a person skilled in the art can combine or modify the features, structures, and effects shown in each embodiment for other embodiments. Therefore, it should be understood that such combinations and modifications are included in the scope of the present application.

[0265] In addition, the above mainly describes the embodiments, but these embodiments are only examples and do not limit the present application, and a person skilled in the art can understand that a variety of changes and applications not mentioned above can be made without departing from the basic features of the embodiments. For example, each component specifically expressed in the embodiments can be changed. In addition, it should be understood that the differences related to such changes and such applications are included in the scope of the present application defined by the attached claims.

Claims

1. An optical path control member comprising: a first substrate; a first electrode provided on an upper surface of the first substrate; a second substrate provided on the first substrate; a second electrode provided on a lower surface of the second substrate; and a light conversion portion provided between the first electrode and the second electrode, wherein the light conversion portion includes partition wall portions and accommodation portions alternately provided, wherein the accommodation portions include a plurality of unit accommodation units spaced apart from each other, wherein the accommodation portions include a dispersion liquid and a plurality of light-absorbing particles dispersed in the dispersion liquid, wherein the light-absorbing particles include first particles and second particles, wherein a particle diameter of the first particles is larger than a particle diameter of the second particles, wherein surfaces of the first particles and the second particles have charges of the same polarity, wherein a total volume of the first particles is larger than a total volume of the second particles in at least one of the unit accommodation units, wherein a ratio of the particle diameter of the second particles to the particle diameter of the first particles is 1:3 to 1:

10. The specific gravity of the first particles and the second particles is 2 or less.

2. The optical path control member according to claim 1, wherein The second particles are 5% to 20% by volume relative to a total volume of the light-absorbing particles in at least one of the unit accommodation units.

3. The optical path control member according to claim 1, wherein The first particles and the second particles include the same material.

4. The optical path control member according to claim 1, wherein The particle diameter of the first particles and the second particles is 500 nm to 700 nm.

5. The optical path control member according to claim 1, wherein When a voltage is applied, the first particles and the second particles move in the same direction as the first electrode or the second electrode.

6. The optical path control member according to claim 1, wherein 7.An optical path control member comprising: a first substrate; a first electrode provided on an upper surface of the first substrate; a second substrate provided on the first substrate; a second electrode provided on a lower surface of the second substrate; and a light conversion portion provided between the first electrode and the second electrode, wherein the light conversion portion includes partition wall portions and accommodation portions alternately provided, wherein a light transmittance of the accommodation portions changes according to application of a voltage, wherein the accommodation portions include a dispersion liquid and light-absorbing particles dispersed in the dispersion liquid, wherein the light-absorbing particles include first particles and second particles, wherein a reflectance of the second particles is larger than a reflectance of the first particles, wherein surfaces of the first particles and the second particles have charges of the same polarity, wherein a content of the first particles is 95% to 99% by weight relative to total particles, wherein a content of the second particles is 1% to 5% by weight relative to the total particles. The first particles absorb light, wherein the reflectance of the second particles is 50% to 90%.

8. The optical path control member according to claim 7, wherein The first particles include carbon black particles, wherein the second particles include metal oxide particles.

9. The optical path control member according to claim 7, wherein ​ ​ 10. The optical path control member according to claim 9, wherein The metal oxide particles include at least one of titanium dioxide (TiO2), zirconium oxide (ZrO2), indium oxide (In2O3), tin oxide (SnO2), and aluminum oxide (Al2O3).

11. The optical path control member according to claim 7, wherein The particle diameter of the first particles and the second particles is 500 nm to 700 nm.

12. The optical path control member according to claim 7, wherein The specific gravity of the first particles is smaller than that of the second particles.

13. A display device comprising: a display panel; and a light path control member provided on the display panel, wherein the light path control member includes: a first substrate; a first electrode provided on an upper surface of the first substrate; a second substrate provided on the first substrate; a second electrode provided on a lower surface of the second substrate; and a light conversion portion provided between the first electrode and the second electrode, wherein the light conversion portion includes partition wall portions and accommodation portions alternately provided, wherein the accommodation portions include a plurality of unit accommodation units spaced apart from each other, wherein the accommodation portions include a dispersion liquid and a plurality of light-absorbing particles dispersed in the dispersion liquid, wherein the light-absorbing particles include first particles and second particles, wherein the particle diameter of the first particles is larger than that of the second particles, and wherein the surfaces of the first particles and the second particles carry charges of the same polarity, wherein the ratio of the particle diameter of the second particles to that of the first particles is 1:3 to 1:

10.

14. The display device according to claim 13, wherein in at least one of the unit accommodation units, the second particles are 5% to 20% by volume relative to the total volume of the light-absorbing particles.

15. The display device of claim 13, wherein, The first particles and the second particles include carbon black.

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