Abstract:
The present invention relates to a film capable of enhancing color purity and correcting brightness for a liquid crystal display device, and a liquid crystal display device comprising the same, and can provide a liquid crystal display device having enhanced color gamut and color purity by introducing, to the inside of an adhesive layer or a coating layer of the liquid crystal display device, a combination of an absorption dye for absorbing a specific wavelength band and a fluorescent dye absorbing a specific wavelength band and emitting light, thereby blocking unnecessary wavelengths except for RGB wavelengths.

Description:
FIELD 
       [0001]    The present invention relates to a color gamut enhancing and brightness compensating film for a liquid crystal display, and a liquid crystal display comprising same. 
       BACKGROUND 
       [0002]    In the past, 40-inch (″) class TVs were mainstream products, but many consumers now buy 50″ class TVs and even 60″ class TVs. When the size competition was over, resolution competition began. Even a year ago, full high definition (HD) (FHD) class TVs belonged to an advanced model, but ultra HD (UHD) TVs now have been rapidly spread on the market. 
         [0003]    Recently, the display market has evolved from large-area, high-resolution competition to color competition. For this reason, competition for the production of a display with excellent color has recently emerged. 
         [0004]    A liquid crystal display (LCD) displays an image using optical properties of liquid crystals, wherein, since a liquid crystal panel displaying the image is a non-emissive device which is not self-luminous, the liquid crystal display has a structure including the liquid crystal panel as well as a back-light unit which is disposed on a rear surface of the liquid crystal panel to provide light to the liquid crystal panel. 
         [0005]    A liquid crystal display has advantages of a small thickness, a light weight, a small consuming power and a low driving voltage when compared to other displays. On the contrary, the liquid crystal display is one step behind the other displays in the sense of color. The color reproduction range of a CRT which is now disappearing amounts to NTSC 80%, and a PDP that has been released recently can achieve the level of NTSC 90%. In addition, an OLED which receives much attention as a next-generation display, may attain up to NTSC 100%. However, an LCD TV may attain at most NTSC 72%. 
         [0006]    Accordingly, there is a need to solve the limitations of the LCD to survive in the depressed display market. 
         [0007]    In particular, it is required in the field to develop a technology for improving the color gamut of the conventional LCD, and a new technology for compensating brightness decrease, which may be accompanied by the improvement of the color gamut. 
       SUMMARY 
       [0008]    Thus, an object of the present invention is to provide a film which may enhance color gamut and compensate brightness decrease in a liquid crystal display by transmitting pure RGB wavelengths emitted from a light source as much as possible and blocking unnecessary wavelengths other than the RGB wavelengths, and a liquid crystal display comprising same. 
         [0009]    To achieve the above object, the present invention provides a liquid crystal display comprising a backlight unit and a liquid crystal panel, wherein the backlight unit, the liquid crystal panel, or both comprise one or more coating layers or adhesive layers, and wherein the one or more coating layers or adhesive layers comprise at least one type of an absorption dye configured to absorb a specific wavelength band, and at least one type of a fluorescent dye configured to absorb and emit a specific wavelength band, in such a manner that both the absorption dye and the fluorescent dye are comprised in the same layer, or each of the absorption dye and the fluorescent dye is comprised in a different layer, respectively, in the one or more coating layers or adhesive layers. 
         [0010]    In addition, the present invention provides a color gamut enhancing and brightness compensating film for a liquid crystal display, comprising a pressure-sensitive adhesive, at least one type of an absorption dye configured to absorb a specific wavelength band, and at least one type of a fluorescent dye configured to absorb and emit a specific wavelength band. 
         [0011]    In addition, the present invention also provides a color gamut enhancing and brightness compensating film for a liquid crystal display, comprising a binder resin, at least one type of an absorption dye configured to absorb a specific wavelength band, and at least one type of a fluorescent dye configured to absorb and emit a specific wavelength band. 
         [0012]    According to the present invention, by using a color gamut enhancing film for a liquid crystal display, which is formed by introducing a combination of absorption dyes configured to absorb a specific wavelength band and a combination of fluorescent dyes configured to absorb and emit a specific wavelength band into an adhesive layer or a coating layer of a liquid crystal display, a color gamut may be enhanced by transmitting pure RGB wavelengths emitted from a light source as much as possible and blocking unnecessary wavelengths other than the RGB wavelengths and a brightness decrease that may be accompanied thereby may be compensated, and thus, a liquid crystal display having the improved color gamut and brightness may be manufactured. In addition, the color gamut enhancing and brightness compensating film according to the present invention may maximize color gamut enhancing effect and brightness compensation effect by freely moving the position thereof according to the characteristics of a display. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0013]      FIG. 1  is a schematic view illustrating a structure of a general liquid crystal display. 
           [0014]      FIGS. 2A to 2D  are schematic views respectively illustrating the structures of a dual brightness enhancement film, a diffusion film, a horizontal prism sheet, and a reflective plate. 
           [0015]      FIGS. 3A to 3E  respectively illustrate the structures of liquid crystal displays according to Examples 1 and 2, and Comparative Examples 1 to 3. 
           [0016]      FIGS. 4A to 4E  respectively illustrate the emission intensity change of liquid crystal displays according to Examples 1 and 2 and Comparative Examples 1 to 3. 
       
    
    
       [0017]      
         [0000]    
       
         
               
             
               
               
             
               
             
               
               
             
           
               
                   
               
               
                 &lt;Explanation of Reference Marks&gt; 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                  10: liquid crystal panel 
                  20: backlight unit 
               
               
                 101: upper polarizing plate 
                 102: first adhesive layer 
               
               
                 103: liquid crystal cell 
                 104: second adhesive layer 
               
               
                 105: lower polarizing plate 
               
             
          
           
               
                 201: dual brightness enhancement film (DBEF) or lower diffusion sheet 
               
             
          
           
               
                 202: horizontal prism sheet 
                 202-1: prism pattern layer 
               
               
                 202-2: prism sheet base 
                 202-3: rear coating layer 
               
               
                 202-4: third beads 
                 203: vertical prism sheet 
               
               
                 204: lower diffusion sheet 
                 205: light guide plate 
               
               
                 206: reflective plate 
                 206-1: fourth beads 
               
               
                 206-2: front coating layer 
                 206-3: reflective plate base 
               
               
                 211: dual brightness enhancement film 
                 221: diffusion film 
               
               
                 221-1: first beads 
                 221-2: diffusion coating layer 
               
               
                 221-3: base 
                 221-4: concealing coating layer 
               
               
                 221-5: second beads 
               
               
                   
               
             
          
         
       
     
       DETAILED DESCRIPTION 
       [0018]    A liquid crystal display of the present invention includes a backlight unit and a liquid crystal panel, wherein the backlight unit, the liquid crystal panel, or both include one or more coating layers or adhesive layers, wherein the one or more coating layers or adhesive layers include at least one type of an absorption dye configured to absorb a specific wavelength band and at least one type of a fluorescent dye configured to absorb and emit a specific wavelength band, in such a manner that both the absorption dye and the fluorescent dye are included in the same layer, or each of the absorption dye and the fluorescent dye is included in a different layer, respectively, in the one or more coating layers or adhesive layers. 
         [0019]    According to the present invention, a combination of at least one type of an absorption dye configured to selectively absorb at least one specific wavelength band and a combination of at least one type of a fluorescent dye configured to absorb and emit a specific wavelength band are introduced into an adhesive layer or a coating layer of the liquid crystal display, by which the color gamut and brightness of a liquid crystal display may be enhanced by improving color gamut by transmitting pure RGB wavelengths from a light source and blocking unnecessary wavelengths other than RGB wavelengths and by compensating brightness decrease that may be accompanied thereby. 
         [0020]    A structure of a general liquid crystal display is illustrated in  FIG. 1 . Referring to  FIG. 1 , a liquid crystal panel  10  may include an upper polarizing plate  101 , a first adhesive layer  102 , a liquid crystal cell  103 , a second adhesive layer  104 , and a lower polarizing plate  105  in a sequentially stacked form, and a backlight unit  20  may sequentially include a dual brightness enhancement film (DBEF) or an upper diffusion sheet  201 , a horizontal prism sheet  202 , a vertical prism sheet  203 , a lower diffusion sheet  204 , a light guide plate  205 , and a reflective plate  206 . 
         [0021]    Referring to  FIGS. 2A to 2D , the dual brightness enhancement film  211  may have a multilayer structure (not shown in the drawings), and the diffusion sheet  221  which is used as an upper diffusion sheet or a lower diffusion sheet may include a diffusion coating layer  221 - 2  having first beads  221 - 1  on one side of a diffusion sheet base  221 - 3  and a concealing coating layer  221 - 4  having second beads  221 - 5  on the opposite side thereof. Furthermore, the horizontal prism sheet  202  may include a prism pattern layer  202 - 1  on one side of a prism sheet base  202 - 2  and a rear coating layer  202 - 3  having third beads  202 - 4  on an opposite side thereof. In addition, the vertical prism sheet may also have the layer configuration the same as or similar to the horizontal prism sheet  202 . Also, the reflective plate  206  may include a front coating layer  206 - 2  having fourth beads  206 - 1  on one side of a reflective plate base  206 - 3 . 
         [0022]    However, the liquid crystal display of the present invention is not limited to the above-described structure and may encompass diverse modifications, if necessary. 
         [0023]    In particular, the backlight unit  20  may include the following laminated structures. 
         [0024]    i) upper diffusion sheet/horizontal prism sheet/vertical prism sheet/lower diffusion sheet 
         [0025]    ii) upper diffusion sheet/horizontal prism sheet/vertical prism sheet 
         [0026]    iii) dual brightness enhancement film/horizontal prism sheet/vertical prism sheet 
         [0027]    iv) micro lens film (MLF)/horizontal prism sheet/vertical prism sheet 
         [0028]    v) upper diffusion sheet/horizontal prism sheet/vertical prism sheet 
         [0029]    Under the basic principle of a liquid crystal display, while light emitted from a light source is guided toward a liquid crystal panel through a light guide plate and then passes through a light diffusion sheet, the light is diffused in horizontal/vertical directions with respect to the surface thereof. Since the light going out of the light diffusion sheet passes through a prism sheet and is prevented from going in a direction other than a front light exit surface, light directivity is improved to narrow a viewing angle, brightness in a direction of the front light exit surface of backlight is increased. In this case, the increase in the brightness may be maximized through light recycling, if a separate sheet such as a dual brightness enhancement film is used in a backlight unit. 
         [0030]    According to the present invention, the backlight unit, the liquid crystal panel, or both include a coating layer or an adhesive layer comprising at least one type of an absorption dye configured to absorb a specific wavelength band and/or a fluorescent dye configured to absorb and emit a specific wavelength band. 
         [0031]    For example, the liquid crystal panel may include at least one type of an absorption dye configured to absorb a specific wavelength band and at least one type of a fluorescent dye configured to absorb and emit a specific wavelength band in one of the first adhesive layer or the second adhesive layer, in such a manner that both the absorption dye and the fluorescent dye are included in the same layer, or each of the absorption dye and the fluorescent dye is included in a different layer, respectively, in the first adhesive layer and the second adhesive layer. 
         [0032]    In addition, the backlight unit may have a coating layer on at least one of one side or both sides of the dual brightness enhancement film or the upper diffusion sheet, one side or both sides of the horizontal prism sheet, one side or both sides of the vertical prism sheet, one side or both sides of the lower diffusion sheet, and one side of the reflective plate (i.e., the light guide plate facing side), wherein the one or more coating layers include at least one type of an absorption dye configured to absorb a specific wavelength band and at least one type of a fluorescent dye configured to absorb and emit a specific wavelength band in one of the first adhesive layer and the second adhesive layer, in such a manner that both the absorption dye and the fluorescent dye are included in the same layer, or each of the absorption dye and the fluorescent dye is included in a different layer, respectively, in the one or more coating layers. 
         [0033]    The adhesive layer or the coating layer including the absorption dye and the fluorescent dye both is referred to as a color gamut enhancing and brightness compensating film, and according to the position of the color gamut enhancing film, particularly, the position of the coating layer, the emission color purity and the brightness loss of a liquid crystal display may vary, and thus, the position thereof may be appropriately controlled according to the need. 
         [0034]    In addition, the absorption dye used in the present invention may be a combination of at least one absorption dye which has a main absorption wavelength band other than RGB wavelengths. 
         [0035]    For example, the absorption dye used in the present invention may have a main absorption wavelength band of 430 nm or less (e.g., 380 nm to 430 nm), 480 nm to 510 nm, or 560 nm to 600 nm as a wavelength band other than RGB wavelengths, and may be a combination of at least one type of the absorption dye. 
         [0036]    Particularly, (i) an absorption dye blocking a wavelength band of 380 nm to 430 nm may include a hydroxybenzotriazole (HB)-based absorption dye, a tris-resorcinol-triazine chromophore (TRTC)-based absorption dye, and a hydroxyphenyl-benzotriazole chromophore (HBC)-based absorption dye; (ii) an absorption dye blocking a wavelength band of 480 nm to 510 nm may include a pyrrole methine (PM)-based absorption dye, a rhodamine (RH)-based absorption dye, and a boron dipyrromethene (BODIBY)-based absorption dye; and (iii) an absorption dye blocking a wavelength band of 560 nm to 600 nm may include a tetraazaporphyrin (TAP)-based absorption dye, a squaraine (SQ)-based absorption dye, and a cyanine (CY)-based absorption dye. 
         [0037]    Preferably, a combination of at least two absorption dyes selected from the group consisting of a hydroxybenzotriazole-based absorption dye, a pyrrole methine-based absorption dye, a rhodamine-based absorption dye, a cyanine-based absorption dye, and a tetraazaporphyrin-based absorption dye may be used, and more preferably, a combination of a hydroxybenzotriazole-based absorption dye, a cyanine-based absorption dye, and a tetraazaporphyrin-based absorption dye may be used. 
         [0038]    In addition, the fluorescent dye used in the present invention may be a combination of at least one fluorescent dye which has a main absorption wavelength band other than RGB wavelengths and has a main emission wavelength band corresponding to the RGB wavelengths. 
         [0039]    For example, the fluorescent dye used in the present invention may have a main absorption wavelength band of 430 nm or less (e.g., 380 nm to 430 nm), 480 nm to 510 nm, or 560 nm to 600 nm other than RGB wavelengths, and a main emission wavelength band of 430 nm to 480 nm, 510 nm to 580 nm, or 600 nm or more (e.g., 600 nm to 650 nm) corresponding to RGB wavelengths, and may be a combination of at least one type of the fluorescent dye. 
         [0040]    Particularly, the fluorescent dye may include an anthracene-based fluorescent dye, an anthraquinone-based fluorescent dye, an arylmethine-based fluorescent dye, an azo-based fluorescent dye, an azomethine-based fluorescent dye, a bimane-based fluorescent dye, a coumarin-based fluorescent dye, an 1,5-diazabicyclo[3,3,0]octadiene-based fluorescent dye, a diketo-pyrrole-based fluorescent dye, a naphthalenol-imine-based fluorescent dye, a naphthalimide-based fluorescent dye, a perylene-based fluorescent dye, a phenolphthalein-based fluorescent dye, a pyrrole methine-based fluorescent dye, a pyran-based fluorescent dye, a pyrene-based fluorescent dye, a porphycene-based fluorescent dye, a porphyrin-based fluorescent dye, a quinacridone-based fluorescent dye, a rhodamine-based fluorescent dye, a rubrene-based fluorescent dye, and a stilbene-based fluorescent dye. 
         [0041]    Preferably, a combination of at least two fluorescent dyes selected from the group consisting of a perylene-based fluorescent dye, an azo-based fluorescent dye, a pyrrole methine-based fluorescent dye, a pyran-based fluorescent dye, and a coumarin-based fluorescent dye may be used. 
         [0042]    More preferably, a combination of the fluorescent dye of the perylene-based fluorescent dye, a pyrrole methine-based fluorescent dye, a pyran-based fluorescent dye, and a coumarin-based fluorescent dye may be used. 
         [0043]    Accordingly, the present invention provides a color gamut enhancing and brightness compensating film for a liquid crystal display, wherein the film includes a pressure-sensitive adhesive, at least one type of an absorption dye configured to absorb a specific wavelength band, and at least one type of a fluorescent dye configured to absorb and emit a specific wavelength band. In this case, the color gamut enhancing and brightness compensating film may be provided as an adhesive layer in the liquid crystal display. 
         [0044]    In addition, the present invention provides a color gamut enhancing and brightness compensating film for a liquid crystal display, wherein the film includes a binder resin, at least one type of an absorption dye configured to absorb a specific wavelength band, and at least one type of a fluorescent dye configured to absorb and emit a specific wavelength band. In this case, the color gamut enhancing and brightness compensating film may be provided as a coating layer in the liquid crystal display. 
         [0045]    The absorption dye may be included in an amount of 0.01 wt % to 10 wt %, and specifically, in an amount of 0.05 wt % to 7 wt %, based on the weight of the color gamut enhancing and brightness compensating film (i.e., an adhesive layer or a coating layer). 
         [0046]    In addition, the fluorescent dye may be included in an amount of 0.01 wt % to 10 wt %, and specifically, in an amount of 0.05 wt % to 7 wt %, based on the weight of the color gamut enhancing and brightness compensating film (i.e., an adhesive layer or a coating layer). 
         [0047]    In addition, the weight ratio of absorption dye:fluorescent dye in the film may be from 0.1:100 to 100:0.1. 
         [0048]    Examples of the pressure-sensitive adhesive used in the adhesive layer (a first adhesive layer and a second adhesive layer) may include at least one adhesive selected from the group consisting of an acryl-based adhesive, a urethane-based adhesive, an epoxy-based adhesive, and a silicone-based adhesive. Specifically, the pressure-sensitive adhesive may be an acryl-based adhesive. For example, the adhesive layer may be formed by being wet coated on the one side or both sides of the upper polarizing plate and the lower polarizing plate, and the thickness of the adhesive layer may be in a range of 2 μm to 100 μm, 5 μm to 100 μm, and preferably, 15 μm to 25 μm. 
         [0049]    Examples of the binder resin used in the coating layer may include at least one resin selected from the group consisting of a polyester-based binder resin, an acryl-based binder resin, a polyurethane-based binder resin, a melamine-based binder resin, a polyvinyl alcohol-based binder resin, and an oxazoline-based binder resin. Specifically, the binder resin may be an acryl-based binder resin. For example, the coating layer may be formed by being wet coated on one side or both sides of a dual brightness enhancement film or an upper diffusion sheet, one side or both sides of a horizontal prism sheet, one side or both sides of a vertical prism sheet, one side or both sides of a lower diffusion sheet, and one side of a reflective plate (i.e., light guide plate facing side), and the thickness of the coating layer may be in a range of 1 μm to 100 μm, 2 μm to 100 μm, and preferably, 2 μm to 15 μm. 
         [0050]    The adhesive layer and the coating layer may further include an ultraviolet blocking agent for blocking UV light according to the need. The ultraviolet blocking agent absorbs (shields) light having a wavelength of 430 nm or less, and may use, for example, a hydroxybenzotriazole (HB)-based absorption dye, a tris-resorcinol-triazine chromophore (TRTC)-based absorption dye, or a hydroxyphenyl-benzotriazole chromophore (HBC)-based absorption dye alone or as a mixture of two or more thereof. The adhesive layer and the coating layer may include the ultraviolet blocking agent in an amount of 0.01 wt % to 10 wt %, and preferably, 0.05 wt % to 7 wt %, based on the weight of the adhesive layer or the coating layer. 
         [0051]    Light transmittance of the color gamut enhancing film according to the present invention may be adjusted according to a brightness range of a liquid crystal display, but, specifically, the color gamut enhancing film may have a visible light transmittance of 30% to 90%, and preferably, 50% to 90%. 
         [0052]    Component layers of each of the backlight unit and the liquid crystal panel constituting the liquid crystal display of the present invention may have a material, a thickness, and a shape, which are commonly accepted in the art, and may be diversely modified if necessary. 
         [0053]    Thus, the liquid crystal display including the color gamut enhancing and brightness compensating film of the present invention may provide enhanced color gamut and brightness by blocking unnecessary wavelengths other than the RGB wavelengths while transmitting the pure RGB wavelengths emitted from a light source as much as possible, and may maximize a color gamut enhancing effect and brightness compensation effect depending on display characteristics by freely moving the position of the color gamut enhancing and brightness compensating film. 
       EXAMPLE 
       [0054]    Hereinafter, the present invention will be explained in more detail referring to embodiments. The following embodiments are intended to further illustrate the present invention without limiting its scope. 
       Example 1 
       [0055]    35 parts by weight of GS1000 manufactured by Soken as an acryl binder resin, 50 parts by weight of methyl ethyl ketone (MEK) as a solvent, and 15 parts by weight of MX-500 manufactured by Soken as beads were mixed, and an absorption dye, SK-d593 manufactured by SK Chemicals was then added thereto in an amount of 0.1 parts by weight based on 100 parts by weight of the mixture to prepare an absorption dye-containing coating composition. One surface of a diffusion film was coated with the absorption dye-containing coating composition using a Mayer bar and dried and cured to form a 5 μm thick concealing coating layer containing the absorption dye. 
         [0056]    Meanwhile, 35 parts by weight of GS1000 manufactured by Soken as an acryl binder resin, 50 parts by weight of methyl ethyl ketone (MEK) as a solvent, and 15 parts by weight of MX-1000 manufactured by Soken as beads were mixed, and a fluorescent dye, FL560 manufactured by SK Chemicals was then added thereto in an amount of 0.1 parts by weight based on 100 parts by weight of the mixture to prepare a fluorescent dye-containing coating composition. The opposite surface of the diffusion film on which the concealing coating layer was formed, was coated with the fluorescent dye-containing coating composition using a Mayer bar and dried and cured to form a 15 μm thick diffusion coating layer containing the fluorescent dye. 
         [0057]    The diffusion film thus obtained was introduced as an upper diffusion sheet in a commercially available liquid crystal display so that the concealing coating layer faced a horizontal prism sheet to manufacture a liquid crystal display of the present invention (see  FIG. 3A ). 
       Example 2 
       [0058]    An absorption dye-containing coating composition was prepared by the same method described in Example 1, and a concealing coating layer containing the absorption dye was formed on one surface of a diffusion film. On the opposite surface of the diffusion film on which the concealing coating layer was formed, a diffusion coating layer was formed by the same method described in Example 1, except that excluding the fluorescent dye was not included in the diffusion coating layer. 
         [0059]    In addition, a fluorescent dye-containing coating composition was prepared by the same method described in Example 1, and the fluorescent dye-containing coating composition was coated on the surface of a horizontal prism sheet where a prism was not formed by using a Mayer bar and dried and cured to form a 5 μm thick rear coating layer containing the fluorescent dye. 
         [0060]    The diffusion film thus obtained was introduced as an upper diffusion sheet, and the horizontal prism sheet thus obtained was used in a commercially available liquid crystal display so that the concealing coating layer of the diffusion film faced the horizontal prism sheet, and the rear coating layer of the horizontal prism sheet faced a vertical prism sheet to manufacture a liquid crystal display of the present invention (see  FIG. 3B ). 
       Comparative Example 1 
       [0061]    A diffusion coating layer and a concealing coating layer were formed on a diffusion film by performing the same procedure described in Example 1, except that none of the absorption dye and the fluorescent dye were included in the diffusion coating layer and the concealing coating layer. 
         [0062]    The diffusion film thus obtained was introduced as an upper diffusion sheet in a commercially available liquid crystal display so that the concealing coating layer faced a horizontal prism sheet to manufacture a comparative liquid crystal display (see  FIG. 3C ). 
       Comparative Example 2 
       [0063]    An absorption dye-containing coating composition was prepared, and a concealing coating layer containing the absorption dye was formed on one surface of a diffusion film by performing the same procedure described in Example 1. On the opposite surface of the diffusion film on which the concealing coating layer was formed, a diffusion coating layer was formed by performing the same procedure described in Example 1, except that a fluorescent dye was not included in the diffusion coating layer. 
         [0064]    The diffusion film thus obtained was introduced as an upper diffusion sheet in a commercially available liquid crystal display so that the concealing coating layer faced a horizontal prism sheet to manufacture a comparative liquid crystal display (see  FIG. 3D ). 
       Comparative Example 3 
       [0065]    A fluorescent dye-containing coating composition was prepared, and a diffusion coating layer containing the fluorescent dye was formed on one surface of a diffusion film by performing the same procedure described in Example 1. On the opposite surface of the diffusion film on which the diffusion coating layer was formed, a concealing coating layer was formed by performing the same procedure described in Example 1, except that an absorption dye was not included in the concealing coating layer. 
         [0066]    The diffusion film thus obtained was introduced as an upper diffusion sheet in a commercially available liquid crystal display so that the concealing coating layer faced a horizontal prism sheet to manufacture a comparative liquid crystal display (see  FIG. 3E ). 
       Experimental Example 
       [0067]    Characteristics and changes in spectrum were measured for the liquid crystal displays manufactured in the examples and comparative examples by using a radiometer (CS-2000, Minolta Co., Ltd.) and the results thereof are presented in Table 1 below and  FIGS. 4A to 4E . In the following Table 1, a color gamut indicates a color reproduction area. 
         [0000]    
       
         
               
               
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                   
                   
                 Comparative 
                 Comparative 
                 Comparative 
               
               
                   
                 Example 1 
                 Example 2 
                 Example 1 
                 Example 2 
                 Example 3 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                 Relative brightness 
                 96.3% 
                 96.2% 
                 100.0% 
                 85.1% 
                 113.3% 
               
               
                 ratio 
               
             
          
           
               
                 Full W 
                 Lv 
                 285.7 
                 296.7 
                 252.6 
                 285.4 
                 336.1 
               
               
                   
                 x 
                 0.3087 
                 0.3150 
                 0.2933 
                 0.3289 
                 0.3307 
               
               
                   
                 y 
                 0.3560 
                 0.3347 
                 0.3164 
                 0.4077 
                 0.3748 
               
               
                 Full R 
                 Lv 
                 52.0 
                 61.3 
                 46.6 
                 50.2 
                 67.7 
               
               
                   
                 x 
                 0.6512 
                 0.6417 
                 0.6481 
                 0.6543 
                 0.6440 
               
               
                   
                 y 
                 0.3291 
                 0.3381 
                 0.3264 
                 0.3314 
                 0.3404 
               
               
                 Full G 
                 Lv 
                 212.5 
                 213.4 
                 184.6 
                 216.0 
                 245.8 
               
               
                   
                 x 
                 0.2921 
                 0.3121 
                 0.2936 
                 0.2933 
                 0.3098 
               
               
                   
                 y 
                 0.6406 
                 0.6250 
                 0.6339 
                 0.6475 
                 0.6314 
               
               
                 Full B 
                 Lv 
                 22.8 
                 23.1 
                 22.0 
                 20.1 
                 24.0 
               
               
                   
                 x 
                 0.1552 
                 0.1561 
                 0.1546 
                 0.1569 
                 0.1569 
               
               
                   
                 y 
                 0.0719 
                 0.0631 
                 0.0601 
                 0.0925 
                 0.0768 
               
               
                 Color 
                 Color 
                 0.123 
                 0.115 
                 0.123 
                 0.122 
                 0.115 
               
               
                 gamut 
                 gamut 
               
               
                   
                 Against 
                 78.0% 
                 72.7% 
                 77.8% 
                 77.0% 
                 72.6% 
               
               
                   
                 NTSC 
               
               
                   
                 Against 
                 81.2% 
                 75.6% 
                 81.0% 
                 80.1% 
                 75.6% 
               
               
                   
                 DCI 
               
             
          
           
               
                 Transmittance loss 
                 −3.7% 
                 −3.8% 
                 — 
                 −14.9% 
                 +13.3% 
               
               
                 (T % loss) 
               
               
                   
               
             
          
         
       
     
         [0068]    As shown in Table 1 above and  FIGS. 4A to 4E , it may be understood that the liquid crystal displays of the examples including the color gamut enhancing and brightness compensating film according to the present invention provide improved color gamut and color purity, while exhibiting excellent brightness.