Patent Publication Number: US-2023161215-A1

Title: Optical path control member and display device comprising same

Description:
TECHNICAL FIELD 
     An embodiment relates to an optical path control member, and to a display device including the same. 
     BACKGROUND ART 
     A light blocking film blocks transmitting of light from a light source, and is attached to a front surface of a display panel which is a display device used for a mobile phone, a notebook, a tablet PC, a vehicle navigation device, a vehicle touch, etc., so that the light blocking film adjusts a viewing angle of light according to an incident angle of light to express a clear image quality at a viewing angle needed by a user when the display transmits a screen. 
     In addition, the light blocking film may be used for the window of a vehicle, building or the like to shield outside light partially to prevent glare, or to prevent the inside from being visible from the outside. 
     That is, the light blocking film may be an optical path control member that controls the movement path of light to block light in a specific direction and transmit light in a specific direction. Accordingly, it is possible to control the viewing angle of the user by controlling a transmission angle of the light by the light blocking film. 
     Meanwhile, such a light blocking film may be divided into a light blocking film that can always control the viewing angle regardless of the surrounding environment or the user&#39;s environment and a switchable light blocking film that allow the user to turn on/off the viewing angle control according to the surrounding environment or the user&#39;s environment. 
     Such a switchable light blocking film may be implemented by switching a pattern part to a light transmitting part and a light blocking part by filling the inside of the pattern part with particles that may move when a voltage is applied and a dispersion liquid for dispersing the particles and by dispersing and aggregating the particles. 
     The dispersion liquid may be disposed by injecting into an intaglio-shaped pattern portion by a capillary injection method. In case of such a capillary injection method, there are problems that a process takes a long time, and non-uniform filling occurs for each pattern portion. 
     Therefore, an optical path control member having a new structure capable of solving the above problems is required. 
     DISCLOSURE 
     Technical Problem 
     An embodiment is directed to providing an optical path control member that may be easily manufactured with improved reliability. 
     Technical Solution 
     An optical path control member according to an embodiment includes: a first substrate; a first electrode disposed on the first substrate; a second substrate disposed on the first substrate; a second electrode disposed under the second substrate; an optical conversion unit disposed between the first electrode and the second electrode; and an adhesive layer between the optical conversion unit and the second electrode, wherein the optical conversion unit includes a partitioning part and an accommodation part alternately disposed, and a dispersion liquid of which light transmittance changes is disposed inside the accommodation part, the dispersion liquid is disposed in direct contact with a bottom surface, an inner surface of the accommodation part, and a lower surface of the adhesive layer, a first contact angle between the dispersion liquid and the bottom surface and the inner surface of the accommodation part is 20° or less, a second contact angle between the dispersion liquid and the lower surface of the adhesive layer is 20° or less, and a difference between the first contact angle and the second contact angle is 1° to 5°. 
     Advantageous Effects 
     An optical path control member according to an embodiment can control a contact angle of a dispersion liquid disposed inside an accommodation part. 
     In detail, a contact angle between an inner surface and a bottom surface of the accommodation part in contact with the dispersion liquid in the accommodation part and a lower surface of an adhesive layer may be controlled to a size of 20° or less. 
     Accordingly, the inner surface and the bottom surface of the accommodation part and the lower surface of the adhesive layer having a contact angle of 20° or less may have properties close to hydrophobicity. Therefore, when the dispersion liquid having hydrophobicity is filled inside the accommodation part, the dispersion liquid is filled through contact surfaces having similar properties, so that a filling speed and filling properties of the dispersion liquid can be improved. 
     In addition, the dispersion liquid may control a difference between a first contact angle with the inner surface and the bottom surface of the accommodation part and a second contact angle with the adhesive layer in a certain size range. Accordingly, a difference between a speed in a region in contact with the accommodation part and a speed in a region in contact with the adhesive layer may be reduced. 
     Therefore, since the dispersion liquid can be filled in the accommodation part at a uniform speed, the uniformity of filling of the dispersion liquid can be improved. 
     In addition, the dispersion liquid may have a certain composition, and a solvent of the dispersion liquid may have permittivity in a certain size range. Accordingly, by controlling the composition of the dispersion liquid and the permittivity of the solvent, the first contact angle and the second contact angle may have a size of 20° or less. 
     That is, in the optical path control member according to the embodiment, it is possible to have improved characteristics and reliability by controlling contact angles of surfaces in contact with the dispersion liquid to improve the filling properties in the accommodation part and to improve the filling uniformity of the plurality of accommodation parts. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIGS.  1  and  2    are perspective views of an optical path control member according to an embodiment. 
         FIGS.  3  and  4    are a perspective view of a first substrate and a first electrode and a perspective view of a second substrate and a second electrode of the optical path control member according to the embodiment. 
         FIGS.  5  and  7    are perspective views for describing that a sealing part is disposed on an optical path control member according to an embodiment. 
         FIGS.  8  and  9    are perspective views for describing that a sealing part is disposed on an optical path control member according to another embodiment. 
         FIGS.  10  and  11    are cross-sectional views taken along line A-A′ in  FIG.  1   . 
         FIG.  12    is an enlarged view of region B in  FIG.  10   . 
         FIG.  13    is an enlarged view of region C in  FIG.  12   . 
         FIG.  14    is an enlarged view of region D in  FIG.  12   . 
         FIGS.  15  to  18    are other cross-sectional views taken along line A-A′ in  FIG.  1   . 
         FIG.  19    is an enlarged view of region E in  FIG.  10   . 
         FIG.  20    is an enlarged view of region F in  FIG.  11   . 
         FIGS.  21  to  28    are views for describing a method of manufacturing an optical path control member according to an embodiment. 
         FIGS.  29  and  30    are cross-sectional views of a display device to which an optical path control member according to an embodiment is applied. 
         FIGS.  31  to  33    are views for describing one embodiment of the display device to which the optical path control member according to the embodiment is applied. 
     
    
    
     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”, or “coupled” to another element, it may include not only when the element is directly “connected” to, or “coupled” to other elements, but also when the element is “connected”, or “coupled” 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 optical path control member according to an embodiment will be described with reference to drawings. The optical path control member described below relates to a switchable optical path control member driven in various modes according to electrophoretic particles moving by applying a voltage. 
     Referring to  FIGS.  1  to  4   , an optical path control member  1000  according to an embodiment may include a first substrate  110 , a second substrate  120 , a first electrode  210 , a second electrode  220 , and an optical conversion unit  300 . 
     The first substrate  110  may support the first electrode  210 . The first substrate  110  may be rigid or flexible. 
     In addition, the first substrate  110  may be transparent. For example, the first substrate  110  may include a transparent substrate capable of transmitting light. 
     The first substrate  110  may 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 substrate  110  may be a flexible substrate having flexible characteristics. 
     Further, the first substrate  110  may be a curved or bended substrate. That is, the optical path control member including the first substrate  110  may also be formed to have flexible, curved, or bent characteristics. Accordingly, the optical path control member according to the embodiment may be changed to various designs. 
     The first substrate  110  may extend in a first direction  1 A, a second direction  2 A, and a third direction  3 A. 
     In detail, the first substrate  110  may include the first direction  1 A corresponding to a length or width direction of the first substrate  110 , a second direction  2 A extending in a direction different from the first direction  1 A and corresponding to the length or width direction of the first substrate  110 , and a third direction  3 A extending in a direction different from the first direction  1 A and the second direction  2 A and corresponding to a thickness direction of the first substrate  110 . 
     For example, the first direction  1 A may be defined as the length direction of the first substrate  110 , the second direction  2 A may be defined as the width direction of the first substrate  110  perpendicular to the first direction  1 A, and the third direction  3 A may be defined as the thickness direction of the first substrate  110 . Alternatively, the first direction  1 A may be defined as the width direction of the first substrate  110 , the second direction  2 A may be defined as the length direction of the first substrate  110  perpendicular to the first direction  1 A, and the third direction  3 A may be defined as the thickness direction of the first substrate  110 . 
     Hereinafter, for convenience of description, the first direction  1 A will be described as the length direction of the first substrate  110 , the second direction  2 A will be described as the width direction of the first substrate  110 , and the third directions  3 A will be described as the thickness direction of the first substrate  110 . 
     The first electrode  210  may be disposed on one surface of the first substrate  110 . In detail, the first electrode  210  may be disposed on an upper surface of the first substrate  110 . That is, the first electrode  210  may be disposed between the first substrate  110  and the second substrate  120 . 
     The first electrode  210  may include a transparent conductive material. For example, the first electrode  210  may include a conductive material having a light transmittance of about 80% or more. For example, the first electrode  210  may include a metal oxide such as indium tin oxide, indium zinc oxide, copper oxide, tin oxide, zinc oxide, titanium oxide, etc. 
     The first electrode  210  may have a thickness of 0.05 μm to 2 μm. 
     Alternatively, the first electrode  210  may include various metals to realize low resistance. For example, the first electrode  210  may include at least one metal of chromium (Cr), nickel (Ni), copper (Cu), aluminum (Al), silver (Ag), molybdenum (Mo). Gold (Au), titanium (Ti), and alloys thereof. 
     Referring to  FIG.  3   , the first electrode  210  may be disposed on the entire surface of one surface of the first substrate  110 . In detail, the first electrode  210  may be disposed as a surface electrode on one surface of the first substrate  110 . However, the embodiment is not limited thereto, and the first electrode  210  may be formed of a plurality of pattern electrodes having a uniform pattern such as a mesh or stripe shape. 
     For example, the first electrode  210  may include a plurality of conductive patterns. In detail, the first electrode  210  may include a plurality of mesh lines crossing each other and a plurality of mesh openings formed by the mesh lines. 
     Accordingly, even though the first electrode  210  includes a metal, the first electrode  210  is not visually recognized from the outside, so that visibility may be improved. In addition, the light transmittance is increased by the openings, so that the brightness of the optical path control member according to the embodiment may be improved. 
     The second substrate  120  may be disposed on the first substrate  110 . In detail, the second substrate  120  may be disposed on the first electrode  210  on the first substrate  110 . 
     The second substrate  120  may include a material capable of transmitting light. The second substrate  120  may include a transparent material. The second substrate  120  may include a material the same as or similar to that of the first substrate  110  described above. 
     For example, the second substrate  120  may 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). This is only an example, but the embodiment is not limited thereto. 
     In addition, the second substrate  120  may be a flexible substrate having flexible characteristics. 
     Further, the second substrate  120  may be a curved or bended substrate. That is, the optical path control member including the second substrate  120  may also be formed to have flexible, curved, or bent characteristics. Accordingly, the optical path control member according to the embodiment may be changed to various designs. 
     The second substrate  120  may also extend in the first direction  1 A, the second direction  2 A, and the third direction  3 A in the same manner as the first substrate  110  described above. 
     In detail, the second substrate  120  may include the first direction  1 A corresponding to a length or width direction of the second substrate  120 , the second direction  2 A extending in a direction different from the first direction  1 A and corresponding to the length or width direction of the second substrate  120 , and the third direction  3 A extending in the direction different from the first direction  1 A and the second direction  2 A and corresponding to the thickness direction of the second substrate  120 . 
     For example, the first direction  1 A may be defined as the length direction of the second substrate  120 , the second direction  2 A may be defined as the width direction of the second substrate  120  perpendicular to the first direction  1 A, and the third direction  3 A may be defined as the thickness direction of the second substrate  120 . 
     Alternatively, the first direction  1 A may be defined as the width direction of the second substrate  120 , the second direction  2 A may be defined as the length direction of the second substrate  120  perpendicular to the first direction  1 A, and the third direction  3 A may be defined as the thickness direction of the second substrate  120 . 
     Hereinafter, for convenience of description, the first direction  1 A will be described as the length direction of the second substrate  120 , the second direction  2 A the second direction  2 A will be described as the width direction of the second substrate  120 , and the third directions  3 A will be described as the thickness direction of the second substrate  120 . 
     The second electrode  220  may be disposed on one surface of the second substrate  120 . In detail, the second electrode  220  may be disposed on a lower surface of the second substrate  120 . That is, the second electrode  220  may be disposed on one surface of the second substrate  120  in which the second substrate  120  and the first substrate  110  face each other. That is, the second electrode  220  may be disposed to face the first electrode  210  on the first substrate  110 . That is, the second electrode  220  may be disposed between the first electrode  210  and the second substrate  120 . 
     The second electrode  220  may include a material the same as or similar to that of the first substrate  110  described above. 
     The second electrode  220  may include a transparent conductive material. For example, the second electrode  220  may include a conductive material having a light transmittance of about 80% or more. As an example, the second electrode  220  may include a metal oxide such as indium tin oxide, indium zinc oxide, copper oxide, tin oxide, zinc oxide, titanium oxide, etc. 
     The second electrode  220  may have a thickness of about 0.1 μm to about 0.5 μm. 
     Alternatively, the second electrode  220  may include various metals to realize low resistance. For example, the second electrode  220  may include at least one metal of chromium (Cr), nickel (Ni), copper (Cu), aluminum (Al), silver (Ag), molybdenum (Mo). gold (Au), titanium (Ti), and alloys thereof. 
     Referring to  FIG.  4   , the second electrode  220  may be disposed on the entire surface of one surface of the second substrate  120 . In detail, the second electrode  220  may be disposed as a surface electrode on one surface of the second substrate  120 . However, the embodiment is not limited thereto, and the second electrode  220  may be formed of a plurality of pattern electrodes having a uniform pattern such as a mesh or stripe shape. 
     For example, the second electrode  220  may include a plurality of conductive patterns. In detail, the second electrode  220  may include a plurality of mesh lines crossing each other and a plurality of mesh openings formed by the mesh lines. 
     Accordingly, even though the second electrode  220  includes a metal, the second electrode  220  is not visually recognized from the outside, so that visibility may be improved. In addition, the light transmittance is increased by the openings, so that the brightness of the optical path control member according to the embodiment may be improved. 
     The first substrate  110  and the second substrate  120  may have sizes corresponding to each other. The first substrate  110  and the second substrate  120  may have sizes the same as or similar to each other. 
     In detail, a first length extending in the first direction  1 A of the first substrate  110  may have a size the same as or similar to a second length L 2  extending in the first direction  1 A of the second substrate  120 . 
     For example, the first length and the second length may have a size of 300 mm to 400 mm. 
     In addition, a first width extending in the second direction  2 A of the first substrate  110  may have a size the same as or similar to a second width extending in the second direction  2 A of the second substrate  120 . 
     For example, the first width and the second width may have a size of 150 mm to 200 mm. 
     In addition, a first thickness extending in the third direction  3 A of the first substrate  110  may have a size the same as or similar to a second thickness extending in the third direction  3 A of the second substrate  120 . 
     For example, the first thickness and the second thickness may have a size of 30 μm to 200 μm. 
     Referring to  FIG.  1   , the first substrate  110  and the second substrate  120  may be disposed to be misaligned from each other. 
     In detail, the first substrate  110  and the second substrate  120  may be disposed at positions misaligned from each other in the first direction  1 A. In detail, the first substrate  110  and the second substrate  120  may be disposed so that side surfaces of the substrates are misaligned from each other. 
     Accordingly, the first substrate  110  may be disposed to protrude in one direction in the first direction  1 A, and the second substrate  120  may be disposed to protrude in the other direction in the first direction  1 A. 
     That is, the first substrate  110  may include a first protrusion protruding in one direction in the first direction  1 A, and the second substrate  110  may include a second protrusion protruding in the other direction in the first direction  1 A. 
     Accordingly, the optical path control member  1000  may include a region where the first electrode  210  is exposed on the first substrate  110  and a region where the second electrode  220  is exposed under the second substrate  120 . 
     That is, the first electrode  210  disposed on the first substrate  110  may be exposed at the first protrusion, and the second electrode  220  disposed under the second substrate  120  may be exposed at the second protrusion. 
     The first electrode  210  and the second electrode  220  exposed at the protrusions may be connected to an external printed circuit board through a connection portion that will be described below. 
     Alternatively, referring to  FIG.  2   , the first substrate  110  and the second substrate  120  may be disposed at positions corresponding to each other. In detail, the first substrate  110  and the second substrate  120  may be disposed such that side surfaces thereof correspond to each other. 
     Accordingly, the first substrate  110  may be disposed to protrude in one direction in the first direction  1 A, and the second substrate  120  may also be disposed in one direction in the first direction  1 A, that is, may be disposed to protrude in the same direction as that of the first substrate  110 . 
     That is, the first substrate  110  may include a first protrusion protruding in one direction in the first direction  1 A, and the second substrate may also include a second protrusion protruding in one direction in the first direction  1 A. 
     That is, the first protrusion and the second protrusion may protrude in the same direction. 
     Accordingly, the optical path control member  1000  may include a region where the first electrode  210  is exposed on the first substrate  110  and a region where the second electrode  220  is exposed under the second substrate  120 . 
     That is, the first electrode  210  disposed on the first substrate  110  may be exposed at the first protrusion, and the second electrode  220  disposed under the second substrate  120  may be exposed at the second protrusion. 
     The first electrode  210  and the second electrode  220  exposed at the protrusions may be connected to an external printed circuit board through a connection portion that will be described below. 
     The optical conversion unit  300  may be disposed between the first substrate  110  and the second substrate  120 . In detail, the optical conversion unit  300  may be disposed between the first electrode  210  and the second electrode  220 . 
     Functional layers may be disposed between at least one of between the optical conversion unit  300  and the first substrate  110  or between the optical conversion unit  300  and the second substrate  120 . 
     In detail, a buffer layer  410  that facilitates adhesion between the optical conversion unit  300  and the first substrate  110  may be disposed between the optical conversion unit  300  and the first substrate  110 . In addition, an adhesive layer  420  that adheres the second electrode  220  and the optical conversion unit  300  may be disposed between the optical conversion unit  300  and the second substrate  120 . 
     The optical conversion unit  300  may include a plurality of partitioning parts and accommodation parts. Optical conversion particles that move by applying a voltage may be disposed in the accommodation part, and light transmission characteristics of the optical path control member may be changed by the optical conversion particles. 
     The optical path control member may include a sealing part. 
     Referring to  FIGS.  5  to  7   , a sealing part  500  may be disposed on an outer surface of the optical path control member. 
     The sealing part  500  may be disposed while covering the outer surface of the optical path control member. In detail, the sealing part  500  may be disposed while partially covering the outer surface of the optical path control member. That is, the sealing part  500  may be disposed while extending from the first substrate  110  toward the second substrate  120  and partially covering the outer surface of the optical path control member. 
     The optical path control member  1000  may include a plurality of side surfaces. In detail, the optical path control member  1000  may include side surfaces extending in the first direction  1 A and facing each other and side surfaces extending in the second direction  2 A and facing each other. 
     The sealing part  500  may be disposed to surround the side surfaces of the optical path control member extending in the first direction  1 A. For example, the sealing part  500  may be disposed to surround the side surfaces of the optical path control member in which the accommodation part  320  in which the optical conversion particles are disposed is exposed from the optical conversion unit  300 . 
     In detail, as shown in  FIG.  5   , the sealing part  500  may be partially disposed on the side surface of the optical path control member while covering the accommodation part  320  exposed from the side surface of the optical path control member. 
     Alternatively, as shown in  FIG.  6   , the sealing part  500  may be entirely disposed on the side surface of the optical path control member while covering the accommodation part  320  exposed from the side surface of the optical path control member. 
     In detail, the accommodation part  320  may be disposed to extend from the optical conversion unit  300  in the second direction  2 A with respect to the first substrate  110  and the second substrate  120 . That is, the plurality of accommodation parts  320  may be disposed to extend in the second direction  2 A while being spaced apart from each other. 
     Accordingly, the accommodation part  320  may be exposed in both lateral directions of the first direction  1 A of the optical conversion unit  300 . The sealing part  500  may be disposed while covering the accommodation part  320  exposed from the optical conversion unit  300  to protect the optical conversion particles inside the exposed accommodation part. 
     That is, the sealing part  500  may be disposed on a part of a side surface of the optical conversion unit  300 , a part of a lower surface of the first substrate  110 , and a part of an upper surface of the second substrate  120 . In other words, the sealing part  500  may be disposed on a part of the side surface of the optical conversion unit  300 , a part of the lower surface of the first substrate  110 , and a part of the upper surface of the second substrate  120  while surrounding the exposed accommodation part of the optical conversion unit. 
     The sealing part  500  may include a resin material having a viscosity of 300 cP or more. 
     Alternatively, referring to  FIG.  7   , the sealing part  500  may be disposed to surround side surfaces of the optical path controlling member extending in the first direction  1 A and side surfaces of the optical path controlling member extending in the second direction  2 A. 
     Accordingly, at least one side surface of the side surfaces in the second direction of the optical conversion unit  300  may also be entirely surrounded by the sealing part  500 . 
     Accordingly, in the optical path control member according to the embodiment, the outer surface of the optical conversion unit  300  may be entirely sealed by the sealing part  500 . That is, it is possible to prevent the penetration of impurities, such as moisture and air, which may penetrate into the accommodation part from the side surface of the optical conversion unit  300  in the second direction. 
     That is, during a manufacturing process of the optical path control member, thicknesses of the side surfaces of the optical conversion unit  300  in the second direction may be different from each other due to a tolerance, and a width of any one of the side surfaces in the second direction is formed to be small, so that impurities that may permeate into the accommodation part may permeate into the accommodation part through the partitioning part. 
     In the optical path control member according to the embodiment, by disposing the sealing part also on the side surface of the optical conversion unit in the second direction, it is possible to effectively prevent the penetration of impurities according to a size of the partitioning part. 
     Meanwhile, although it is illustrated that the sealing part is disposed on the outer surface of the optical path member in  FIGS.  5  to  7   , the embodiment is not limited thereto, and the sealing part may be disposed on an upper surface of the optical conversion unit  300 . 
     Referring to  FIGS.  8  and  9   , unlike  FIGS.  1  and  2   , the first substrate  110  and the second substrate  120  may have different sizes. 
     In detail, a first length extending in the first direction  1 A of the first substrate  110  may have a size the same as or similar to a second width L 2  extending in the first direction  1 A of the second substrate  120  within a size range of 300 mm to 400 mm. 
     In addition, a first width extending in the second direction  2 A of the first substrate  110  and a second width extending in the second direction of the second substrate  120  may have different sizes within a size range of 150 mm to 200 mm. 
     For example, the second width extending in the second direction of the second substrate  120  may be smaller than a size of the first width extending in the second direction  2 A of the first substrate  110 . 
     Accordingly, both ends of the optical conversion unit  300  in the second direction may be disposed to be spaced apart from the second substrate  120 . 
     A sealing part  500  and a dam part  600  which are respectively disposed on the optical conversion unit may be disposed at both ends of the optical conversion unit  300  in the second direction. 
     When the optical conversion material is injected into the accommodation part, the dam part  600  may determine an injection part and an outlet part, and the sealing part  500  may seal the injection part and the outlet part after the optical conversion material is injected. 
     That is, the sealing part  500  may be disposed on the partitioning part  310  while filling the accommodation part  320  of the optical conversion unit  300  at both ends of the optical conversion unit  300  in the second direction. 
     Referring to  FIGS.  10  and  11   , the optical conversion unit  300  may include a partitioning part  310  and an accommodation part  320 . 
     The partitioning part  310  may be defined as a partitioning part dividing the accommodation part. That is, the partitioning part  310  may transmit light as a barrier region dividing a plurality of accommodation parts. In addition, the accommodation part  320  may be defined as a variable region where the accommodation part  320  is switched to a light blocking part and a light transmitting part by applying a voltage. 
     The partitioning part  310  and the accommodation part  320  may be alternately disposed with each other. The partitioning part  310  and the accommodation part  320  may be disposed to have different widths. For example, a width of the partitioning part  310  may be greater than that of the accommodation part  320 . 
     The partitioning part  310  and the accommodation part  320  may be alternately disposed with each other. In detail, the partitioning part  310  and the accommodation part  320  may be alternately disposed with each other. That is, each of the partitioning parts  310  may be disposed between the accommodation parts  320  adjacent to each other, and each of the accommodation parts  320  may be disposed between the adjacent partitioning parts  310 . 
     The partitioning part  310  may include a transparent material. The partitioning part  310  may include a material that may transmit light. 
     The partitioning part  310  may include a resin material. For example, the partitioning part  310  may include a photo-curable resin material. As an example, the partitioning part  310  may include a UV resin or a transparent photoresist resin. Alternatively, the partitioning part  310  may include urethane resin or acrylic resin. 
     The partitioning part  310  may transmit light incident on any one of the first substrate  110  and the second substrate  120  toward another substrate. 
     For example, in  FIGS.  10  and  11   , light may be emitted from the first substrate  110  by a light source disposed under the first substrate  110 , and the light may be incident toward the second substrate  120 . In this case, the partitioning part  310  may transmit the light, and the transmitted light may move toward the second substrate  120 . 
     The accommodation part  320  may include the dispersion liquid  320   a  and the optical conversion particles  320   b . In detail, the accommodation part  320  may be filled by injecting the dispersion liquid  320   a . A plurality of optical conversion particles  320   b  may be dispersed in the dispersion liquid  320   a.    
     The dispersion liquid  320   a  may be a material for dispersing the optical conversion particles  320   b . The dispersion liquid  320   a  may include a transparent material. The dispersion liquid  320   a  may include a non-polar solvent. In addition, the dispersion liquid  320   a  may include a material capable of transmitting light. For example, the dispersion liquid  320   a  may include at least one of a halocarbon-based oil, a paraffin-based oil, and isopropyl alcohol. 
     The optical conversion particles  320   b  may be disposed to be dispersed in the dispersion liquid  320   a . In detail, the plurality of optical conversion particles  320   b  may be disposed to be spaced apart from each other in the dispersion liquid  320   a.    
     The optical conversion particles  320   b  may include a material capable of absorbing light. That is, the optical conversion particles  320   b  may be light absorbing particles. The optical conversion particles  320   b  may have a color. For example, the optical conversion particles  320   b  may have a black-based color. As an example, the optical conversion particles  320   b  may include carbon black. 
     The optical conversion particles  320   b  may have a polarity by charging surfaces thereof. For example, the surfaces of the optical conversion particles  320   b  may be charged with a negative (−) charge. Accordingly, the optical conversion particles  320   b  may move toward the first electrode  210  or the second electrode  220  by applying a voltage. 
     The light transmittance of the accommodation part  320  may be changed by the optical conversion particles  320   b . In detail, the accommodation part  320  may be switched to the light blocking part and the light transmitting part by changing the light transmittance due to the movement of the optical conversion particles  320   b . That is, the accommodation part  320  may change the transmittance of light passing through the accommodation part  320  by dispersion liquid and aggregation of the optical conversion particles  320   b  disposed inside the dispersion liquid  320   a.    
     For example, the optical path control member according to the embodiment may be converted from a first mode to a second mode or from the second mode to the first mode by a voltage applied to the first electrode  210  and the second electrode  220 . 
     In detail, in the optical path control member according to the embodiment, the accommodation part  320  becomes the light blocking part in the first mode, and light of a specific angle may be blocked by the accommodation part  320 . That is, a viewing angle of the user viewing from the outside is narrowed, so that the optical path control member may be driven in a privacy mode. 
     In addition, in the optical path control member according to the embodiment, the accommodation part  320  becomes the light transmitting part in the second mode, and in the optical path control member according to the embodiment, light may be transmitted through both the partitioning part  310  and the accommodation part  320 . That is, the viewing angle of the user viewing from the outside may be widened, so that the optical path control member may be driven in a share mode. 
     Switching from the first mode to the second mode, that is, the conversion of the accommodation part  320  from the light blocking part to the light transmitting part may be realized by movement of the optical conversion particles  320   b  of the accommodation part  320 . That is, the optical conversion particles  320   b  may have a charge on the surfaces thereof and may move toward the first electrode or the second electrode by applying a voltage according to characteristics of the charge. That is, the optical conversion particles  320   b  may be electrophoretic particles 
     In detail, the accommodation part  320  may be electrically connected to the first electrode  210  and the second electrode  220 . 
     In this case, when a voltage is not applied to the optical path control member from the outside, the optical conversion particles  320   b  of the accommodation part  320  are uniformly dispersed in the dispersion liquid  320   a , and the accommodation part  320  may block light by the optical conversion particles. Accordingly, in the first mode, the accommodation part  320  may be driven as the light blocking part. 
     Alternatively, when a voltage is applied to the optical path control member from the outside, the optical conversion particles  320   b  may move. For example, the optical conversion particles  320   b  may move toward one end or the other end of the accommodation part  320  by a voltage transmitted through the first electrode  210  and the second electrode  220 . That is, the optical conversion particles  320   b  may move from the accommodation part  320  toward the first electrode  210  or the second electrode  220 . 
     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 optical conversion particles  320   b  charged with the negative charge may move toward a positive electrode of the first electrode  210  and the second electrode  220  using the dispersion liquid  320   a  as a medium. 
     That is, when the voltage is applied to the first electrode  210  and/or the second electrode  220 , as shown in  FIG.  10   , the optical conversion particles  320   b  may move toward the first electrode  210  in the dispersion liquid  320   a . That is, the optical conversion particles  320   b  may move in one direction, and the accommodation part  320  may be driven as the light transmitting part. 
     Alternatively, when the voltage is not applied to the first electrode  210  and/or the second electrode  220 , as shown in  FIG.  11   , the optical conversion particles  320   b  may be uniformly dispersed in the dispersion liquid  320   a  to drive the accommodation part  320  as the light blocking part. 
     Accordingly, the optical path control member according to the embodiment may be driven in two modes according to a user&#39;s surrounding environment. That is, when the user requires light transmission only at a specific viewing angle, the accommodation part 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 accommodation part as the light transmitting part. 
     Therefore, since the optical path control member according to the embodiment may be implemented in two modes according to the user&#39;s requirement, the optical path control member may be applied regardless of the user&#39;s environment. 
     As described above, the dispersion liquid  320   a  in which the optical conversion particles  320   b  are dispersed may be disposed inside the accommodation part  320 . 
     The dispersion liquid  320   a  may be disposed in each accommodation part in the direction from the injection part toward the outlet part using a capillary injection method. In this case, according to characteristics of the dispersion liquid  320   a  and characteristics of the inside of the accommodation part  320  in contact with the dispersion liquid  320   a  and the adhesive layer  420 , filling properties of the injected dispersion liquid may be changed. 
     That is, when the inside of the accommodation part  320  in contact with the dispersion liquid and the adhesive layer  420  has hydrophobicity, the dispersion liquid  320   a  having hydrophobicity may have improved filling properties inside the accommodation part. 
     Therefore, in the optical path control member according to the embodiment, by controlling permittivity and composition of the dispersion liquid  320   a  and controlling a contact angle between the dispersion liquid and the inside of the accommodation part  320  and the adhesive layer  420  so that the characteristics of the accommodation part and the adhesive layer. Has hydrophobicity similar to that of the dispersion liquid, thereby improving the filling properties of the dispersion liquid. 
     Referring to  FIGS.  12  to  14   , the dispersion liquid  320   a  disposed in the accommodation part  320  may be disposed in direct contact with a bottom surface BS of the accommodation part  320 , an inner surface IS of the accommodation part  320 , and a lower surface of the adhesive layer  420 . 
     The dispersion liquid of the optical path control member according to the embodiment may have different contact angles on the inner surface IS of the accommodation part  320  and the lower surface of the adhesive layer  420 . 
     In detail, when the dispersion liquid  320   a  is in contact with the bottom surface BS of the accommodation part  320  and the inner surface IS of the accommodation part, the dispersion liquid  320   a  may have a first contact angle θ 1 . In addition, when the dispersion liquid  320   a  is in contact with the lower surface of the adhesive layer  420 , the dispersion liquid  320   a  may have a second contact angle θ 2 . 
     Here, the first contact angle θ 1  may be defined as an angle between a surface of a droplet of the dispersion liquid and the bottom and inner surfaces of the accommodation part when the dispersion liquid is dropped on the bottom and inner surfaces of the accommodation part. 
     In addition, the second contact angle θ 2  may be defined as an angle between a surface of a droplet of the dispersion liquid and the lower surface of the adhesive layer when the dispersion liquid is dropped on the lower surface of the adhesive layer. 
     The first contact angle θ 1  and the second contact angle θ 2  may be 20° or less. 
     In detail, the first contact angle θ 1  may be 20° or less. In more detail, the first contact angle θ 1  may be 5° to 20°. In more detail, the first contact angle θ 1  may be 8° to 15°. 
     When the first contact angle θ 1  has a contact angle exceeding 20°, the bottom surface BS of the accommodation part  320  in contact with the dispersion liquid  320   a  and the inner surface IS of the accommodation part have a property close to hydrophilicity, and thus the dispersion liquid  320   a  having hydrophobicity may not be easily filled in the accommodation part. 
     In addition, when the first contact angle θ 1  is formed to be less than 5°, a weight % of the optical conversion particles  320   b  dispersed inside the dispersion liquid  320   a  may be changed, and thus the optical conversion characteristics of the optical path control member may be deteriorated. 
     In addition, the second contact angle θ 2  may be 20° or less. In more detail, the second contact angle θ 2  may be 3° to 15°. In more detail, the second contact angle θ 2  may be 5° to 10°. 
     When the second contact angle θ 2  has a contact angle exceeding 20°, the adhesive layer in contact with the dispersion liquid  320   a  has a property close to hydrophilicity, and thus the dispersion liquid  320   a  having hydrophobicity may not be easily filled in the accommodation part by the adhesive layer. 
     In addition, when the second contact angle θ 2  is formed to be less than 3°, a weight % of the optical conversion particles  320   b  dispersed inside the dispersion liquid  320   a  may be changed, and thus the optical conversion characteristics of the optical path control member may be deteriorated. 
     That is, since both the first contact angle θ 1  of the bottom surface BS of the accommodation part  320  and the inner surface IS of the accommodation part that are in contact with the dispersion liquid  320   a  having hydrophobicity and the second contact angle θ 2  of the lower surface of the adhesive layer  420  that is in contact with the dispersion liquid  320   a  are formed to be 20° or less, the bottom surface BS of the accommodation part  320 , the inner surface IS of the accommodation part, and the lower surface of the adhesive layer  420  may have hydrophobicity. That is, the bottom surface BS of the accommodation part  320 , the inner surface IS of the accommodation part, and the lower surface of the adhesive layer  420  may also have hydrophobicity similar to that of the dispersion liquid  302   a.    
     In addition, the first contact angle θ 1  and the second contact angle θ 2  may be different. In detail, a size of the first contact angle θ 1  may be greater than a size of the second contact angle θ 2 . In addition, a difference θ 1 -θ 2  between the first contact angle θ 1  and the second contact angle θ 2  may be 10° or less. In detail, the difference θ 1 -θ 2  between the first contact angle θ 1  and the second contact angle θ 2  may be 1° to 5°. In more detail, the difference θ 1 -θ 2  between the first contact angle θ 1  and the second contact angle θ 2  may be 3° to 5°. 
     By forming the difference between the first contact angle θ 1  and the second contact angle θ 2  within the above range, filling properties and filling uniformity of the dispersion liquid filled inside the accommodation part may be improved. 
     In detail, it is possible to reduce a difference between a filling speed of the dispersion liquid in contact with the accommodation part while having the first contact angle and a filling speed of the dispersion liquid in contact with the adhesive layer while having the second contact angle. Therefore, the filling speed of the dispersion liquid filled inside the accommodation part may be filled at a similar speed regardless of a type of surfaces with which the dispersion liquid is in contact. 
     Therefore, it is possible to improve the filling uniformity of the plurality of accommodation parts, and it is possible to improve the filling properties and the filling speed in each accommodation part. 
     The dispersion liquid  320   a  may include a solvent, optical conversion particles  320   b , and a dispersant. In order to control the sizes of the first contact angle θ 1  and the second contact angle θ 2 , a composition ratio of the dispersion liquid  320   a  may be controlled at a certain ratio. 
     In detail, the dispersion liquid  320   a  may include a solvent including at least one of a halocarbon-based oil, a paraffin-based oil, and isopropyl alcohol. 
     The solvent may be included in an amount of 89.5 wt % to 94.7 wt % with respect to a total weight of the dispersion liquid. 
     In addition, the optical conversion particles  320   b  may include carbon black particles. The optical conversion particles  320   b  may be included in an amount of 1 wt % to 3.5 wt % with respect to the total weight of the dispersion liquid. 
     In addition, the dispersion liquid may include a dispersant capable of uniformly dispersing the optical conversion particles in the solvent. 
     The dispersant may be included in an amount of 1 wt % to 1.8 wt % with respect to the total weight of the dispersion liquid. 
     When the solvent, the optical conversion particles  320   b , and the dispersant are out of the weight % range, the first contact angle of the dispersion liquid and the accommodation part and the second contact angle of the dispersion liquid and the adhesive layer increase, and accordingly, the accommodation part and the adhesive layer is close to hydrophilicity, and thus the filling properties of the dispersion liquid having hydrophobicity may be deteriorated. 
     In addition, the solvent may have permittivity of a certain size. In detail, the permittivity of the solvent may be less than 7.5. In more detail, the permittivity of the solvent may be 1 to less than 7.5. In more detail, the permittivity of the solvent may be 2 to 3. 
     When the permittivity of the solvent is 7.5 or more, even though the composition ratio is satisfied, the first contact angle of the dispersion liquid and the accommodation part and the second contact angle of the dispersion liquid and the adhesive layer increase by the permittivity, and accordingly, the accommodation part and the adhesive layer is close to hydrophilicity, and thus the filling properties of the dispersion liquid having hydrophobicity may be deteriorated. 
     Meanwhile, the accommodation part may be disposed in a different shape in consideration of driving characteristics and the like. 
     Referring to  FIGS.  15  and  16   , in an optical path control member according to another embodiment, both ends of an accommodation part  320  may be disposed in contact with a buffer layer  410  and an adhesive layer  420  unlike  FIGS.  10  and  11   . 
     For example, a lower portion of the accommodation part  320  may be disposed in contact with the buffer layer  410 , and an upper portion of the accommodation part  320  may be disposed in contact with the adhesive layer  420 . 
     Accordingly, a distance between the accommodation part  320  and the first electrode  210  may be reduced, so that the voltage applied from the first electrode  210  may be smoothly transmitted to the accommodation part  320 . 
     Accordingly, a moving speed of the optical conversion particles  320   b  inside the accommodation part  320  may be improved, and thus the driving characteristics of the optical path control member may be improved. 
     In addition, referring to  FIGS.  17  and  18   , in the optical path control member according to the embodiment, unlike  FIGS.  10  and  11   , the accommodation part  320  may be disposed while having a constant inclination angle θ. 
     In detail, referring to  FIGS.  17  and  18   , the accommodation part  320  may be disposed to have an inclination angle θ of greater than 0° to less than 90° with respect to the first substrate  110 . In detail, the accommodation part  320  may extend upward while having an inclination angle θ of greater than 0° to less than 90° with respect to one surface of the first substrate  110 . 
     Accordingly, when the optical path control member is used together with a display panel, moire caused by an overlapping phenomenon between a pattern of the display panel and the accommodation part  320  of the optical path control member may be alleviated, thereby improving user visibility. 
     The optical path control member according to the embodiment may control the contact angle of the dispersion liquid disposed inside the accommodation part. 
     In detail, the contact angle between the inner surface and the bottom surface of the accommodation part in contact with the dispersion liquid in the accommodation part and the lower surface of the adhesive layer may be controlled to a size of 20° or less. 
     Accordingly, the inner surface and the bottom surface of the accommodation part and the lower surface of the adhesive layer having a contact angle of 20° or less may have properties close to hydrophobicity. Therefore, when the dispersion liquid having hydrophobicity is filled inside the accommodation part, the dispersion liquid is filled through contact surfaces having similar properties, so that the filling speed and filling properties of the dispersion liquid may be improved. 
     In addition, the dispersion liquid may control the difference between the first contact angle with the inner surface and the bottom surface of the accommodation part and the second contact angle with the adhesive layer in a certain size range. Accordingly, a difference between a speed in a region in contact with the accommodation part and a speed in a region in contact with the adhesive layer may be reduced. 
     Therefore, since the dispersion liquid may be filled in the accommodation part at a uniform speed, the uniformity of filling of the dispersion liquid may be improved. 
     In addition, the dispersion liquid may have a certain composition, and the solvent of the dispersion liquid may have permittivity in a certain size range. Accordingly, by controlling the composition of the dispersion liquid and the permittivity of the solvent, the first contact angle and the second contact angle may have a size of 20° or less. 
     That is, in the optical path control member according to the embodiment, it is possible to have improved characteristics and reliability by controlling contact angles of surfaces in contact with the dispersion liquid to improve the filling properties in the accommodation part and to improve the filling uniformity of the plurality of accommodation parts. 
     Hereinafter, an optical path control member according to another embodiment will be described with reference to  FIGS.  19  and  20   . 
     Referring to  FIGS.  19  and  20   , an optical conversion material may be disposed in the accommodation part  320 . In detail, an optical conversion material having a constant viscosity may be disposed inside the accommodation part  320 . 
     The optical conversion material may include a solvent  320   a , optical conversion particles  320   b , and a liquid crystal  320   c . The optical conversion particles  320   b  and the liquid crystal  320   c  may be dispersed in the solvent  320   a.    
     That is, the accommodation part  320  may be filled by injecting with the solvent  320   a  in which the optical conversion particles  320   b  and the liquid crystal  320   c  are dispersed. 
     The solvent  320   a  may be a material that disperses the optical conversion particles  320   b  and the liquid crystal  320   c . The dispersion liquid  320   a  may include a transparent material. The solvent  320   a  may include a material capable of transmitting light. 
     The solvent  320   a  may include a polar solvent or a non-polar solvent. 
     For example, the solvent  320   a  may include a material having an aromatic ring to have polarity. For example, the solvent  320   a  may include a polar hydrocarbon having an aromatic ring. 
     Alternatively, the solvent  320   a  may include at least one of non-polar halocarbon-based oil, paraffin-based oil, and isopropyl alcohol. 
     The optical conversion particles  320   b  may be disposed to be dispersed in the solvent  320   a . In detail, the plurality of optical conversion particles  320   b  may be disposed to be spaced apart from each other in the solvent  320   a.    
     The liquid crystal  320   c  may be dispersed in the solvent  320   a.    
     As the optical conversion material includes the liquid crystal  320   c , the optical conversion material may have a low viscosity. Accordingly, the moving speed of the optical conversion particles  320   b  dispersed in the solvent  320   a  may be improved. That is, it is possible to improve the moving speed of the optical conversion particles  320   b  in inverse proportion to the viscosity of the solvent. 
     Accordingly, the moving speed of the optical conversion particles  320   b  may be increased, thereby improving a driving speed of the optical path controlling member. 
     In addition, as the optical conversion material includes the liquid crystal  320   c , the optical conversion material may have low volatility. 
     That is, in case of a general low-viscosity material, there is a problem that an evaporation rate is increased due to a decrease in a flash point, but the optical conversion material may prevent the problem by the liquid crystal  320   c  while implementing low viscosity, thereby having low volatility while implementing low viscosity. 
     In addition, when a voltage is applied to the optical path control member, the liquid crystal  320   c  may facilitate movement of the moving optical conversion particles  320   b.    
     Referring to  FIG.  19   , when a voltage is not applied to the optical path control member, the liquid crystal  320   c  may be arranged in an irregular direction in the solvent  320   a.    
     However, referring to  FIG.  20   , when a voltage is applied to the optical path control member, the liquid crystal  320   c  may be arranged in a regular direction in the solvent  320   a . That is, a length direction of the liquid crystal  320   c  may be arranged in a direction in which the first electrode  210  and the second electrode  220  face each other. 
     Accordingly, when the optical conversion particles  320   b  move toward the first electrode  210  or the second electrode  220 , the optical conversion particles  320   b  may easily move by the liquid crystal  320   c  arranged in a movement direction of the optical conversion particles  320   b , thereby improving the driving speed of the optical conversion particles. 
     The liquid crystal  320   c  may be included in a constant weight % range with respect to a total weight of the optical conversion material. The liquid crystal  320   c  may be included in an amount of 10 wt % or less with respect to the total weight of the optical conversion material. In detail, the liquid crystal  320   c  may be included in an amount of 1 wt % to 10 wt % with respect to the total weight of the optical conversion material. In more detail, the liquid crystal  320   c  may be included in an amount of 1 wt % to 5 wt % with respect to the total weight of the optical conversion material. 
     When the liquid crystal  320   c  is included in an amount exceeding 10 wt % with respect to the total amount of the optical conversion material, a phenomenon in which the liquid crystals  320   c  are aggregated with each other in the solvent  320   a  may occur. 
     In particular, when the solvent  320   a  includes a non-polar solvent, the liquid crystals  320   c  having polarity may not be dispersed and may be aggregated with each other. 
     The optical conversion particles  320   b  and the liquid crystal  320   c  may be included in different weight % ranges with respect to the total weight of the optical conversion material. 
     For example, the weight % of the optical conversion particles  320   b  with respect to the total weight of the optical conversion material may be greater than or smaller than the weight % of the liquid crystal  320   c  with respect to the total weight of the optical conversion material. 
     In detail, a ratio of the weight % of the optical conversion particles  320   b  with respect to the total weight of the optical conversion material and the weight % of the liquid crystal  320   c  with respect to the total weight of the optical conversion material may be 1:0.2 to 1:3. 
     When the ratio of the weight % of the optical conversion particles  320   b  with respect to the total weight of the optical conversion material and the weight % of the liquid crystal  320   c  with respect to the total weight of the optical conversion material is less than 1:0.2, a content of the liquid crystal in the optical conversion material is reduced, so that the viscosity of the optical conversion material may be increased, and thus the driving speed of the optical path controlling member may be lowered. 
     In addition, when the ratio of the weight % of the optical conversion particles  320   b  with respect to the total weight of the optical conversion material and the weight % of the liquid crystal  320   c  with respect to the total weight of the optical conversion material exceeds 1:3, an effect of improving the driving speed may be insignificant compared to an amount in which the content of the liquid crystal in the optical conversion material is increased, and the liquid crystals may be agglomerated with each other, and thus the driving characteristics of the optical path control member may be deteriorated. 
     Meanwhile, as described above, the solvent  320   a  may have a polarity. When the solvent  320   a  has a polarity, dispersibility of the liquid crystal  320   c  disposed in the solvent  320   a  may be improved. 
     That is, since both the solvent  320   a  and the liquid crystal  320   c  have polarity, the aggregation of the liquid crystals  320   c  with each other in the solvent  320   a  may be minimized. 
     A polar magnitude of the solvent  320   a  and a polar magnitude of the liquid crystal  320   c  may be different from each other. In detail, the polar magnitude of the solvent  320   a  may be smaller than the polar magnitude of the liquid crystal  320   c.    
     A difference between the polar magnitude of the solvent  320   a  and the polar magnitude of the liquid crystal  320   c  may be 0.08 to 0.8. 
     When the difference between the polar magnitude of the solvent  320   a  and the polar magnitude of the liquid crystal  320   c  is less than 0.08, the moving speed of the optical conversion material in the solvent may be reduced due to the increase in the polar magnitude of the solvent. In addition, when the difference between the polar magnitude of the solvent  320   a  and the polar magnitude of the liquid crystal  320   c  exceeds 0.8, the liquid crystal may be aggregated with each other in the solvent due to a polarity difference between the solvent and the liquid crystal. 
     Hereinafter, a method of manufacturing the optical path control member according to the embodiment will be described with reference to  FIGS.  21  to  28   . A method of manufacturing the optical path control member to be described below will be mainly described with respect to a case in which the first substrate and the second substrate have the same size as shown in  FIGS.  1  and  2   . 
     Referring to  FIG.  21   , a first substrate  110  and an electrode material for forming a first electrode are prepared. Then, the first electrode may be formed by coating or depositing the electrode material on one surface of the first substrate. In detail, the electrode material may be formed on the entire surface of the first substrate  110 . Accordingly, the first electrode  210  formed as a surface electrode may be formed on the first substrate  110 . 
     Subsequently, referring to  FIG.  22   , a resin layer  350  may be formed by coating a resin material on the first electrode  210 . In detail, the resin layer  350  may be formed by applying a urethane resin or an acrylic resin on the first electrode  210 . 
     In this case, before disposing the resin layer  350 , a buffer layer  410  may be additionally disposed on the first electrode  210 . In detail, by disposing the resin layer  350  on the buffer layer  410  after disposing the buffer layer  410  having good adhesion to the resin layer  350  on the first electrode  210 , it is possible to improve the adhesion of the resin layer  350 . 
     For example, the buffer layer  410  may include an organic material including a lipophilic group such as —CH—, an alkyl group, etc. Having good adhesion to the electrode and a hydrophilic group such as —NH, —OH, —COOH, etc. Having a good adhesion to the resin layer  410 . 
     The resin layer  350  may be disposed on a partial region of the first substrate  110 . That is, the resin layer  350  may be disposed in an area smaller than that of the first substrate  110 . Accordingly, a region where the resin layer  350  is not disposed and the first electrode  210  is exposed may be formed on the first substrate  110 . In addition, when the buffer layer  410  is disposed on the first electrode  210 , a region where the buffer layer  410  is exposed may be formed. 
     Subsequently, referring to  FIG.  23   , the resin layer  350  may be patterned to form a plurality of partitioning parts  310  and a plurality of accommodation parts  320  in the resin layer  350 . In detail, an engraved portion may be formed in the resin layer  350  to form an engrave-shaped accommodation part  320  and the emboss-shaped partitioning part  310  between the engraved portions. 
     Accordingly, an optical conversion unit  300  including the partitioning part  310  and the accommodation part  320  may be formed on the first substrate  110 . 
     In addition, the buffer layer  410  exposed on the first electrode  210  may be removed to expose the first electrode  210  in a region where the first substrate  110  protrudes. 
     Subsequently, referring to  FIG.  24   , a second electrode and an electrode material for forming a second substrate  120  and are prepared. Then, the second electrode may be formed by coating or depositing the electrode material on one surface of the second substrate. In detail, the electrode material may be formed on the entire surface of the second substrate  120 . Accordingly, the second electrode  220  formed as a surface electrode may be formed on the second substrate  120 . 
     A size of the second substrate  120  may be smaller than that of the first substrate  110 . In addition, the size of the second substrate  120  may be smaller than that of the resin layer  350 . 
     In detail, a size of a second length extending in a first direction of the second substrate  120  may be greater than a third length extending in the first direction of the resin layer  350 , and a size of a second width extending in a second direction of the second substrate  120  may be smaller than a size of a third width extending in the second direction of the resin layer  350 . 
     Subsequently, referring to  FIG.  25   , an adhesive layer  420  may be formed by coating an adhesive material on the second electrode  220 . In detail, a light-transmitting adhesive layer capable of transmitting light may be formed on the second electrode  220 . For example, the adhesive layer  420  may include an optical transparent adhesive layer OCA. 
     The adhesive layer  420  may be disposed on a partial region of the optical conversion unit  300 . That is, the adhesive layer  420  may be disposed in an area smaller than that of the optical conversion unit  300 . Accordingly, a region where the adhesive layer  410  is not disposed and the optical conversion unit  300  is exposed may be formed on the optical conversion unit  300 . 
     Subsequently, referring to  FIG.  26   , the first substrate  110  and the second substrate  120  may be adhered. In detail, the second substrate  120  may be disposed on the optical conversion unit  300 , and the second substrate  120  and the optical conversion unit  300  may be adhered through the adhesive layer  420  disposed under the second substrate  120 . 
     The optical conversion unit  300  and the second substrate  120  may be sequentially stacked in the thickness direction of the first substrate  110 , the optical conversion unit  300 , and the second substrate  120 . 
     In this case, since the second substrate  120  is disposed in a size smaller than the size of the resin layer  350 , a plurality of partitioning parts  310  and accommodation parts  320  may be exposed in a region where the second substrate  120  is not disposed on the optical conversion unit  300 . 
     In detail, since the size of the second width extending in the second direction of the second substrate  120  is smaller than the size of the third width extending in the second direction of the resin layer  350 , the plurality of partitioning parts  310  and the accommodation part  320  may be exposed in an end region of at least one of one end and the other end facing in a width direction of the resin layer  350 . 
     Subsequently, an optical conversion material  380  may be injected between the partitioning parts  310 , that is, the accommodation parts  320 . In detail, an optical conversion material in which light absorbing particles such as carbon black are dispersed in an electrolyte solvent including a paraffinic solvent and the like may be injected between the partitioning parts, that is, the accommodation parts  320 . That is, the optical conversion material  380  including the above-described dispersion liquid may be injected into the accommodation part. 
     For example, after disposing a dam extending in a length direction of the optical conversion unit  300  on the accommodation part and the partitioning part of the optical conversion unit  300  on which the second substrate  120  is not disposed, the electrolyte solvent may be injected into the accommodation part  320  by a capillary injection method between the dam and a side surface of the optical conversion unit  300 . 
     Subsequently, referring to  FIG.  27   , one optical path control member may be manufactured by cutting the optical conversion unit  300 . In detail, the optical conversion unit  300  may be cut in the length direction of the optical conversion unit  300 . That is, the optical conversion unit  300 , the buffer layer  410  under the optical conversion unit  300 , the first electrode  210 , and the first substrate  110  may be cut along the dotted line shown in  FIG.  22   . A plurality of optical path control members A and B may be formed by the cutting process, and  FIG.  23    is a view showing one of the plurality of optical path control members. 
     In detail, the optical conversion unit  300  may be cut so that the side surfaces of the first substrate  110 , the second substrate  120 , and the optical conversion unit  300  in the width direction may be disposed on the same plane or both ends of the second substrate in the second direction are disposed on a cross-section perpendicular to both ends of the optical conversion unit in the second direction. 
     Accordingly, both ends of the second substrate  120 , the second electrode  220 , or the adhesive layer  420  in the second direction and both ends of the optical conversion unit  300  in the second direction may be disposed on the same plane. 
     That is, the both ends of the adhesive layer  420  in the second direction and the both ends of the optical conversion unit  300  in the second direction may be connected to each other. 
     Alternatively, the both ends of the second substrate  120 , the second electrode  220 , or the adhesive layer  420  in the second direction may be disposed more outside than the both ends of the optical conversion unit  300  in the second direction according to an error during the process. 
     Subsequently, the buffer layer  410  disposed on the first substrate  110  and/or the adhesive layer  420  disposed under the second substrate  120  may be partially removed to form a connection portion in which the electrode is exposed. In detail, when the buffer layer  410  is disposed on the first electrode where the optical conversion unit  300  is not disposed on an upper surface of the first substrate  110 , a first connection portion  211  may be formed on the first substrate  110  by removing a part of the first buffer layer  410  to expose the first electrode  210  or by not disposing the buffer layer  410  on the first electrode on which the optical conversion unit  300  is not disposed from the beginning. In addition, when the adhesive layer  420  is disposed on the second electrode where the optical conversion unit  300  is not disposed on a lower surface of the second substrate  120 , a second connection portion  221  may be formed under the second substrate  120  by removing a part of the adhesive layer  420  or by not disposing the adhesive layer on the second electrode on which the optical conversion unit  300  is not disposed during the adhesive process. 
     A printed circuit board or a flexible printed circuit board may be connected to the connection portions through an anisotropic conductive film (ACF) or the like, and the printed circuit board may be connected to an external power source to apply a voltage to the optical path control member. 
     Subsequently, referring to  FIG.  28   , a sealing part  500  may be disposed through a sealing material. In detail, the sealing part  500  may be disposed in contact with each of side surfaces extending in the first direction, each of side surfaces extending in the second direction of the optical path control member, and upper and lower portions of the optical path control member. 
     Alternatively, the sealing part  500  may be disposed in contact with each of the side surfaces extending in the first direction of the optical path controlling member and the upper and lower portions of the optical path controlling member. 
     Accordingly, by sealing the accommodation part exposed to the outside by the sealing part  500 , that is, the dispersion liquid in which the optical conversion particles are dispersed from the outside, denaturation of the optical conversion particles due to external moisture, oxygen, or the like may be prevented. 
     Hereinafter, the present invention will be described in more detail through the filling properties of the dispersion liquid of the optical path control member according to Examples and Comparative Examples. Such Examples are merely illustrative in order to describe the present invention in more detail. Therefore, the present invention is not limited to the Examples. 
     Example 1 
     After disposing a first electrode on a first substrate, a resin layer was formed on the first electrode. In this case, the resin layer included an acrylate-based resin. 
     Then, the resin layer was patterned to form an optical conversion unit including a partitioning part and an accommodation part between the partitioning parts on the resin layer. 
     Next, after a second electrode was disposed on a second substrate, an adhesive layer was disposed on the second electrode, and the second electrode and the optical conversion unit were adhered. 
     Then, after forming a dam spaced apart from one end and the other end of the accommodation part, an optical conversion material was injected through a space between the dam and the accommodation part. 
     In this case, the optical conversion material included a solvent, carbon black, and a dispersant. 
     Then, a first contact angle θ 1  between contact surfaces of the optical conversion material and the accommodation part and a second contact angle θ 2  between the optical conversion material and the adhesive layer were measured. 
     Example 2 
     After an optical path control member was manufactured in the same manner as in Example 1 except that a composition ratio of the optical conversion material was different as shown in Table 1, the first contact angle θ 1  between contact surfaces of the optical conversion material and the accommodation part and the second contact angle θ 2  between the optical conversion material and the adhesive layer were measured. 
     Example 3 
     After the optical path control member was manufactured in the same manner as in Example 1 except that the composition ratio of the optical conversion material was different as shown in Table 1, the first contact angle θ 1  between the contact surfaces of the optical conversion material and the accommodation part and the second contact angle θ 2  between the optical conversion material and the adhesive layer were measured. 
     Example 4 
     After the optical path control member was manufactured in the same manner as in Example 1 except that the composition ratio of the optical conversion material was different as shown in Table 1, the first contact angle θ 1  between the contact surfaces of the optical conversion material and the accommodation part and the second contact angle θ 2  between the optical conversion material and the adhesive layer were measured. 
     Ccomparative Example 1 
     After manufacturing the optical path control member in the same manner as in Example 1, except that the composition ratio of the optical conversion material and permittivity of a solvent were different as shown in Table 1, the first contact angle θ 1  between the contact surfaces of the optical conversion material and the accommodation part and the second contact angle θ 2  between the optical conversion material and the adhesive layer were measured. 
     Ccomparative Example 2 
     After manufacturing the optical path control member in the same manner as in Example 1, except that the composition ratio of the optical conversion material and the permittivity of the solvent were different as shown in Table 1, the first contact angle θ 1  between the contact surfaces of the optical conversion material and the accommodation part and the second contact angle θ 2  between the optical conversion material and the adhesive layer were measured. 
     Comparative Example 3 
     After manufacturing the optical path control member in the same manner as in Example 1, except that the composition ratio of the optical conversion material and the permittivity of the solvent were different as shown in Table 1, the first contact angle θ 1  between the contact surfaces of the optical conversion material and the accommodation part and the second contact angle θ 2  between the optical conversion material and the adhesive layer were measured. 
     Comparative Example 4 
     After manufacturing the optical path control member in the same manner as in Example 1, except that the composition ratio of the optical conversion material and the permittivity of the solvent were different as shown in Table 1, the first contact angle θ 1  between the contact surfaces of the optical conversion material and the accommodation part and the second contact angle θ 2  between the optical conversion material and the adhesive layer were measured. 
     
       
         
           
               
               
               
               
               
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 Solvent 
                 Solute 
                 Dispersant 
                 Solvent 
                 First contact 
                 Second contact 
                 Filling 
               
               
                   
                 (wt %) 
                 (wt %) 
                 (wt %) 
                 permittivity 
                 angle (°) 
                 angle (°) 
                 properties 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
            
               
                 Example 1 
                 94.7 
                 3.5 
                 1.6 
                 2.1 
                 8.3 
                 4.4 
                 high 
               
               
                 Example 2 
                 93.5 
                 3.5 
                 3 
                 2.1 
                 10.9 
                 7.4 
                 high 
               
               
                 Example 3 
                 91.5 
                 3.5 
                 5 
                 2.1 
                 14.1 
                 8.9 
                 high 
               
               
                 Example 4 
                 89.5 
                 3.5 
                 7 
                 2.1 
                 18.7 
                 15 
                 high 
               
               
                 Comparative 
                 93.5 
                 3.5 
                 3 
                 7.5 
                 20.8 
                 47 
                 low 
               
               
                 Example 1 
               
               
                 Comparative 
                 83.5 
                 3.5 
                 15 
                 7.5 
                 16.7 
                 23 
                 low 
               
               
                 Example 2 
               
               
                 Comparative 
                 93.5 
                 3.5 
                 3 
                 40 
                 45.3 
                 54 
                 low 
               
               
                 Example 3 
               
               
                 Comparative 
                 90.5 
                 3.5 
                 6 
                 2.1 
                 17.8 
                 4.1 
                 medium 
               
               
                 Example 4 
               
               
                   
               
            
           
         
       
     
     Referring to Table 1, in the optical conversion material of the optical path control member according to Examples, both the first contact angle θ 1  and the second contact angle θ 2  have a value of 20° or less, and accordingly, it can be seen that both the resin layer and the adhesive layers have hydrophobicity similar to that of the dispersion liquid. 
     Accordingly, it can be seen that the filling properties of the optical conversion material according to Examples are improved. 
     On the other hand, in the optical conversion material of the optical path control member according to Comparative Examples 1 to 3, at least one of the first contact angle θ 1  and the second contact angle θ 2  has a value exceeding 20°, and thus, it can be seen that any one of the resin layer and the adhesive layer has hydrophilicity different from that of the dispersion. 
     Accordingly, it can be seen that the filling properties of the optical conversion material according to Comparative Examples 1 to 3 are deteriorated. 
     In addition, referring to Comparative Example 4, when a difference between the first contact angle θ 1  and the second contact angle θ 2  exceeds 10°, it can be seen that the filling properties are deteriorated depending on a difference in the filling speed of the optical conversion material in contact with the adhesive layer and the resin layer. 
     Hereinafter, referring to  FIGS.  29  to  33   , a display device to which an optical path control member according to an embodiment is applied will be described. 
     Referring to  FIGS.  29  and  30   , an optical path control member  1000  according to an embodiment may be disposed on or under a display panel  2000 . 
     The display panel  2000  and the optical path control member  1000  may be disposed to be adhered to each other. For example, the display panel  2000  and the optical path control member  1000  may be adhered to each other via an adhesive layer  1500 . The adhesive layer  1500  may be transparent. For example, the adhesive layer  1500  may include an adhesive or an adhesive layer including an optical transparent adhesive material. 
     The adhesive layer  1500  may include a release film. In detail, when adhering the optical path control member and the display panel, the optical path control member and the display panel may be adhered after the release film is removed. 
     Meanwhile, referring to  FIGS.  29  and  30   , one end or one end and the other end of the optical path control member may protrude, and the optical conversion unit may not be disposed at the protruding portion. The protrusion region is an electrode connection portion in which the first electrode  210  and the second electrode  220  are exposed, and may connect an external printed circuit board and the optical path control member through the electrode connection portion. 
     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, the optical path control member may be formed under the liquid crystal panel. That is, when a surface viewed by the user in the liquid crystal panel is defined as an upper portion of the liquid crystal panel, the optical path control member may be disposed under the liquid crystal panel. The display panel  2000  may be formed in a structure in which the first′ substrate  2100  including a thin film transistor (TFT) and a pixel electrode and the second′ substrate  2200  including color filter layers are bonded to each other with a liquid crystal layer interposed therebetween. 
     In addition, the display panel  2000  may 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 electrolyte are formed at the first′ substrate  2100  and the second′ substrate  2200  is bonded to the first′ substrate  2100  with the liquid crystal layer interposed therebetween. That is, a thin film transistor may be formed on the first′ substrate  2100 , 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′ substrate  2100 . At this point, in order to improve an aperture ratio and simplify a masking process, the black electrolyte may be omitted, and a common electrode may be formed to function as the black electrolyte. 
     In addition, when the display panel  2000  is the liquid crystal display panel, the display device may further include a backlight unit  3000  providing light from a rear surface of the display panel  2000 . 
     That is, as shown in  FIG.  29   , the optical path control member may be disposed under the liquid crystal panel and on the backlight unit  3000 , and the optical path control member may be disposed between the backlight unit  3000  and the display panel  2000 . 
     Alternatively, as shown in  FIG.  30   , when the display panel  2000  is an organic light emitting diode panel, the optical path control member may be formed on the organic light emitting diode panel. That is, when the surface viewed by the user in the organic light emitting diode panel is defined as an upper portion of the organic light emitting diode panel, the optical path control member may be disposed on the organic light emitting diode panel. The display panel  2000  may include a self-luminous element that does not require a separate light source. In the display panel  2000 , a thin film transistor may be formed on the first′ substrate  2100 , 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. In addition, the second′ substrate  2200  configured to function as an encapsulation substrate for encapsulation may be further included on the organic light emitting element. 
     That is, light emitted from the display panel  2000  or the backlight unit  3000  may move from the second substrate  120  toward the first substrate  110  of the optical path control member. 
     In addition, although not shown in drawings, a polarizing plate may be further disposed between the optical path control member  1000  and the display panel  2000 . The polarizing plate may be a linear polarizing plate or an external light reflection preventive polarizing plate. For example, when the display panel  2000  is a liquid crystal display panel, the polarizing plate may be the linear polarizing plate. Further, when the display panel  2000  is the organic light emitting diode panel, the polarizing plate may be the external light reflection preventing polarizing plate. 
     In addition, an additional functional layer  1300  such as an anti-reflection layer, an anti-glare, or the like may be further disposed on the optical path control member  1000 . Specifically, the functional layer  1300  may be adhered to one surface of the first substrate  110  of the optical path control member. Although not shown in drawings, the functional layer  1300  may be adhered to the first substrate  110  of the optical path control member via an adhesive layer. In addition, a release film for protecting the functional layer may be further disposed on the functional layer  1300 . 
     Further, a touch panel may be further disposed between the display panel and the optical path control member. 
     It is shown in the drawings that the optical path control member is disposed at an upper portion of the display panel, but the embodiment is not limited thereto, and the optical path 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, or between a second substrate and a first substrate of the display panel, or the like. 
     In addition, it is shown in the drawings that the optical conversion unit of the optical path control member according to the embodiment is in a direction parallel or perpendicular to an outer surface of the second substrate, but the optical conversion unit is formed to be inclined at a predetermined angle from the outer surface of the second substrate. Through this, a moire phenomenon occurring between the display panel and the optical path control member may be reduced. 
     Referring to  FIGS.  31  to  33   , an optical path control member according to an embodiment may be applied to various display devices. 
     Referring to  FIGS.  31  to  33   , the optical path control member according to the embodiment may be applied to a display device that displays a display. 
     For example, when power is applied to the optical path control member as shown in  FIG.  31   , the accommodation part functions as the light transmitting part, so that the display device may be driven in the share mode, and when power is not applied to the optical path control member as shown in  FIG.  32   , the accommodation part functions as the light blocking part, so that the display device may be driven in the privacy mode. 
     Accordingly, a user may easily drive the display device in the privacy mode or a normal mode by applying power. 
     Light emitted from the backlight unit or the self-luminous element may move from the first substrate toward the second substrate. Alternatively, the light emitted from the backlight unit or the self-luminous element may also move from the second substrate toward the first substrate. 
     In addition, referring to  FIG.  33   , the display device to which the optical path control member according to the embodiment is applied may also be applied inside a vehicle. 
     For example, the display device including the optical path 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 optical path 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. 
     Further, the optical path 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.