Patent Publication Number: US-2019179185-A1

Title: Display device

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority from and the benefit of Korean Patent Application No. 10-2017-0167717, filed on Dec. 7, 2017, which is hereby incorporated by reference for all purposes as if fully set forth herein. 
     BACKGROUND 
     Field 
     Exemplary embodiments of the invention relate generally to a display device. More specifically, exemplary embodiments of the present invention relate to a display device with improved color reproducibility and luminance. 
     Discussion of the Background 
     A liquid crystal display may include two field generating electrodes, a liquid crystal layer, a color filter, and a polarization layer. Light generated from a light source reaches a viewer after passing through the liquid crystal layer, the color filter, and the polarization layer. In this case, there is a problem that light loss is generated between the polarization layer and the color filter, etc. The light loss may also be generated in a display device such as an organic light emitting diode display as well as the liquid crystal display. 
     In order to implement a display device with reduced light loss and having high color reproducibility, a display device including a color conversion display panel using a semiconductor nanocrystal is proposed. 
     The above information disclosed in this Background section is only for understanding of the background of the inventive concepts, and, therefore, it may contain information that does not constitute prior art. 
     SUMMARY 
     Exemplary embodiments relate to a display device with improved color reproducibility and luminance. 
     A display device according to an exemplary embodiment includes a thin film transistor array panel including a first pixel electrode connected to the thin film transistor and a second pixel electrode adjacent to the first pixel electrode and connected to a second thin film transistor; and a color conversion display panel overlapping the thin film transistor array panel. The color conversion display panel includes a color conversion layer including a semiconductor nanocrystal and a transmissive layer. The thin film transistor array panel includes a first shielding electrode positioned between the first pixel electrode and the second pixel electrode and a second shielding electrode positioned adjacent to the first pixel electrode and separated from the first shielding electrode. The first shielding electrode and the second shielding electrode are configured to receive different voltages. 
     The first shielding electrode may be configured to receive a voltage that may be larger than a voltage that the second shielding electrode is configured to receive. 
     The first shielding electrode may be configured to receive a higher voltage than the voltage applied to the first pixel electrode, and the second shielding electrode may be configured to receive a voltage that is the same as or lower than the voltage applied to the pixel electrode. 
     The first pixel electrode may include a first vertical stem part, a first horizontal stem part, and a first minute branch part, the first pixel electrode may be positioned between the first shielding electrode and the second shielding electrode, and the first vertical stem part may be positioned adjacent to the first shielding electrode. 
     The first horizontal stem part may be orthogonal at the center of the first vertical stem part. 
     The liquid crystal layer overlapping the first pixel electrode may include two domains with different arrangement directions of the liquid crystal molecules. 
     The second pixel electrode includes a second vertical stem part, a second horizontal stem part, and a second minute branch part. The second pixel electrode is positioned between the first shielding electrode and a different second shielding electrode, and the second vertical stem part of the second pixel electrode is positioned adjacent to the first shielding electrode. The first pixel electrode and the second pixel electrode may be symmetrical with reference to the first shielding electrode. 
     The first shielding electrode, the second shielding electrode, and the first pixel electrode may be positioned on a same layer. 
     Liquid crystal molecules positioned between the first vertical stem part and the first shielding electrode may be arranged parallel to liquid crystal molecules overlapping the first minute branch part. 
     The color conversion display panel may further include at least one of a light filter layer, an over-coating layer, and a polarization layer positioned between the color conversion layer and the thin film transistor array panel and between the transmissive layer and the thin film transistor array panel. 
     A display device according to an exemplary embodiment includes: a thin film transistor array panel; a color conversion display panel overlapping the thin film transistor array panel; and a liquid crystal layer positioned between the thin film transistor array panel and the color conversion display panel and including a plurality of liquid crystal molecules. The color conversion display panel includes a color conversion layer including a semiconductor nanocrystal and a transmissive layer. The thin film transistor array panel includes a first pixel electrode including a first vertical stem part, a first horizontal stem part, and a first minute branch part; a second pixel electrode adjacent to the first pixel electrode and including a second vertical stem part, a second horizontal stem part, and a second minute branch part; and a shielding electrode positioned between the first pixel electrode and the second pixel electrode, and liquid crystal molecules positioned between the first vertical stem part and the shielding electrode are arranged parallel to liquid crystal molecules overlapping the first minute branch part. 
     The shielding electrode may include a first shielding electrode and a second shielding electrode configured to receive different voltages. The first shielding electrode may be positioned between the first pixel electrode and the second pixel electrode and the second shielding electrode may be positioned adjacent to the first pixel and separated from the first shielding electrode. 
     The first shielding electrode may be configured to receive a voltage larger than a voltage that the second shielding electrode is configured to receive. 
     The first minute branch part may overlap the color conversion layer and the transmissive layer. 
     The color conversion display panel may further include a light blocking member positioned between the color conversion layer and the transmissive layer, and the light blocking member may overlap the shielding electrode. 
     The color conversion display panel may further include a light blocking member positioned between the color conversion layer and the transmissive layer. The light blocking member may overlap the shielding electrode. 
     The liquid crystal layer overlapping the first pixel electrode may include two domains in which the arrangement directions of the liquid crystal molecules are different. 
     The first pixel electrode and the second pixel electrode may be symmetrical with reference to the first shielding electrode. 
     The first shielding electrode, the second shielding electrode, and the first pixel electrode are positioned on a same layer. 
     The first shielding electrode may be configured to receive a higher voltage than a voltage applied to the first pixel electrode. The second shielding electrode may be configured to receive a voltage that is the same as or lower than the voltage applied to the first pixel electrode. 
     A plurality of first shielding electrodes may be connected to each other, and a plurality of second shielding electrodes may be connected to each other. 
     Additional features of the inventive concepts will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the inventive concepts. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention, and together with the description serve to explain the inventive concepts. 
         FIG. 1  is a schematic top plan view of a display device according to an exemplary embodiment. 
         FIG. 2  is a top plan view of a plurality of pixels according to an exemplary embodiment. 
         FIG. 3  is a cross-sectional view taken along a line of  FIG. 2 . 
         FIG. 4  is a view to schematically explain a movement of a liquid crystal molecule according to an exemplary embodiment of  FIG. 2 . 
         FIG. 5  is a view to schematically explain a movement of a liquid crystal molecule according to a comparative example. 
         FIG. 6  is a top plan view of a pixel of a display device according to a variation in the exemplary embodiment of  FIG. 2 . 
         FIG. 7  is a luminance simulation image of a pixel according to Comparative Example 1, Comparative Example 2, Comparative Example 3, Exemplary Embodiment 1, and Exemplary Embodiment 2. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various exemplary embodiments or implementations of the invention. As used herein “embodiments” and “implementations” are interchangeable words that are non-limiting examples of devices or methods employing one or more of the inventive concepts disclosed herein. It is apparent, however, that various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring various exemplary embodiments. Further, various exemplary embodiments may be different, but do not have to be exclusive. For example, specific shapes, configurations, and characteristics of an exemplary embodiment may be used or implemented in another exemplary embodiment without departing from the inventive concepts. 
     Unless otherwise specified, the illustrated exemplary embodiments are to be understood as providing exemplary features of varying detail of some ways in which the inventive concepts may be implemented in practice. Therefore, unless otherwise specified, the features, components, modules, layers, films, panels, regions, and/or aspects, etc. (hereinafter individually or collectively referred to as “elements”), of the various embodiments may be otherwise combined, separated, interchanged, and/or rearranged without departing from the inventive concepts. 
     The use of cross-hatching and/or shading in the accompanying drawings is generally provided to clarify boundaries between adjacent elements. As such, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for particular materials, material properties, dimensions, proportions, commonalities between illustrated elements, and/or any other characteristic, attribute, property, etc., of the elements, unless specified. Further, in the accompanying drawings, the size and relative sizes of elements may be exaggerated for clarity and/or descriptive purposes. When an exemplary embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. Also, like reference numerals denote like elements. 
     When an element, such as a layer, is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it may be directly on, connected to, or coupled to the other element or layer or intervening elements or layers may be present. When, however, an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. To this end, the term “connected” may refer to physical, electrical, and/or fluid connection, with or without intervening elements. Further, the first direction, the second direction, and the third direction are not limited to three axes of a rectangular coordinate system, such as the x, y, and z-axes, and may be interpreted in a broader sense. For example, the first direction, the second direction, and the third direction may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Although the terms “first,” “second,” etc. may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. Thus, a first element discussed below could be termed a second element without departing from the teachings of the disclosure. 
     Spatially relative terms, such as “beneath,” “below,” “under,” “lower,” “above,” “upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), and the like, may be used herein for descriptive purposes, and, thereby, to describe one elements relationship to another element(s) as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of an apparatus in use, operation, and/or manufacture in addition to the orientation depicted in the drawings. For example, if the apparatus in the drawings is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below. Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and, as such, the spatially relative descriptors used herein interpreted accordingly. 
     The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms, “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Moreover, the terms “comprises,” “comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It is also noted that, as used herein, the terms “substantially,” “about,” and other similar terms, are used as terms of approximation and not as terms of degree, and, as such, are utilized to account for inherent deviations in measured, calculated, and/or provided values that would be recognized by one of ordinary skill in the art. 
     Various exemplary embodiments are described herein with reference to sectional and/or exploded illustrations that are schematic illustrations of idealized exemplary embodiments and/or intermediate structures. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, exemplary embodiments disclosed herein should not necessarily be construed as limited to the particular illustrated shapes of regions, but are to include deviations in shapes that result from, for instance, manufacturing. In this manner, regions illustrated in the drawings may be schematic in nature and the shapes of these regions may not reflect actual shapes of regions of a device and, as such, are not necessarily intended to be limiting. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure is a part. Terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein. 
     Now, a display device according to an exemplary embodiment will be described with reference to  FIG. 1 ,  FIG. 2 ,  FIG. 3 ,  FIG. 4 , and  FIG. 5 .  FIG. 1  is a schematic top plan view of a display device according to an exemplary embodiment.  FIG. 2  is a top plan view of a plurality of pixels according to an exemplary embodiment.  FIG. 3  is a cross-sectional view taken along a line III-III′ of  FIG. 2 .  FIG. 4  is a view to schematically explain a movement of liquid crystal molecules according to an exemplary embodiment of  FIG. 2 .  FIG. 5  is a view to schematically explain a movement of liquid crystal molecules according to a comparative example. 
     First, referring to  FIG. 1 , the display device according to an exemplary embodiment of the present invention may include a first shielding electrode  192   a  and a second shielding electrode  192   b  positioned on a first substrate  110 . The first shielding electrode  192   a  and the second shielding electrode  192   b  may be alternately positioned along a first direction (a gate line extending direction) and may have a shape extends along a second direction (a data line extending direction). 
     The plurality of first shielding electrodes  192   a  included in the display device may be connected to each other and receive a predetermined first voltage through a first pad part  193   a.  The plurality of second shielding electrodes  192   b  may receive a predetermined second voltage through a second pad part  193   b.  The first voltage and the second voltage may be different, and as an example, the first voltage may be larger than the second voltage. 
     Next, the structure of the display device will be described in detail with reference to  FIG. 2  and  FIG. 3 . 
     The display device according to an exemplary embodiment includes a light unit  500 , a thin film transistor array panel  100 , a color conversion display panel  300  separated from and overlapping the thin film transistor array panel  100 , and a liquid crystal layer  3  positioned between the thin film transistor array panel  100  and the color conversion display panel  300 . 
     The light unit  500  is positioned at a rear surface of the thin film transistor array panel  100  along a third direction. The light unit  500  may include a light source generating light, and a light guide (not shown) receiving the light and guiding the received light toward the thin film transistor array panel  100 . 
     The light unit  500  may include any light source emitting blue light, and may include a light emitting diode (LED) as an example. Instead of the light unit  500  including the blue light source, the light unit  500  may include a white light source or an ultraviolet ray light source. However, the display device using the light unit  500  including the blue light source will be described hereinafter. 
     The light source may be an edge type disposed on at least one lateral surface of the light guide or a direct type positioned directly below the light guide, but is not limited thereto. 
     The thin film transistor array panel  100  includes a first polarization layer  12  positioned between the first substrate  110  and the light unit  500 . The first polarization layer  12  polarizes light incident from the light unit  500  to the first substrate  110 . 
     The first polarization layer  12  may be at least one of a deposited polarization layer, a coated polarization layer, and a printed polarization layer, but is not limited thereto. As an example, it may be a wire grid polarizer and but is not limited thereto. 
     The thin film transistor array panel  100  may include a gate line  121  extending in a first direction between the first substrate  110  and the liquid crystal layer  3  and including a gate electrode  124 , a gate insulating layer  140  positioned between a gate line  121  and the liquid crystal layer  3 , a semiconductor layer  154  positioned between the gate insulating layer  140  and the liquid crystal layer  3 , a data line  171  positioned between the semiconductor layer  154  and the liquid crystal layer  3  and extending in a second direction, a source electrode  173  connected to the data line  171 , a drain electrode  175  separated from the source electrode  173 , and a passivation layer  180  positioned between the data line  171  and the liquid crystal layer  3 . 
     The semiconductor layer  154  forms a channel in a part that is not covered by the source electrode  173  and the drain electrode  175 . The gate electrode  124 , the semiconductor layer  154 , the source electrode  173 , and the drain electrode  175  form one thin film transistor Tr. 
     A pixel electrode  191  is positioned on the passivation layer  180 . The pixel electrode  191  may be physically and electrically connected to the drain electrode  175  through a contact hole  185  included in the passivation layer  180 . 
     The pixel electrode  191  according to an exemplary embodiment includes a horizontal stem part  191   a,  a vertical stem part  191   b  connected to the horizontal stem part  191   a  to be crossed therewith, and a plurality of minute branch parts  191   c  extending from the horizontal stem part  191   a  and the vertical stem part  191   b  along a diagonal direction. The horizontal stem part  191   a  according to an exemplary embodiment may be connected to the vertical stem part  191   b  to be crossed therewith at a center of the vertical stem part  191   b.  The minute branch part  191   c  forms an angle of about 45 degrees or 135 degrees with the horizontal stem part  191   a.  The minute branch parts  191   c  extending in different diagonal directions from each other may be crossed with each other. 
     One pixel electrode  191  may include a first region Da and a second region Db divided with reference to the horizontal stem part  191   a  and the vertical stem part  191   b.  Arrangement directions of liquid crystal molecules  31  may be different in the first region Da and the second region Db. In detail, a side of the minute branch part  191   c  distorts an electric field to form a horizontal component determining an inclination direction of the liquid crystal molecules  31 . The horizontal component of the electric field may be substantially parallel to the side of the minute branch parts  191   c.  The liquid crystal molecules  31  may be inclined along a direction parallel to a length direction of the minute branch parts  191   c.  Because one pixel electrode  191  includes the minute branch parts  191   c  that are inclined in two different directions from each other, the directions in which the liquid crystal molecules  31  are inclined may be two directions. Two domains having the different alignment directions of the liquid crystal molecules  31  may be formed in the liquid crystal layer  3 . 
     The first shielding electrode  192   a  and the second shielding electrode  192   b  may be positioned on the same layer as the pixel electrode  191 . The first shielding electrode  192   a  and the second shielding electrode  192   b  are disposed to be separated from the pixel electrode  191  and extend to be substantially parallel to the data line  171 . The first shielding electrode  192   a  and the second shielding electrode  192   b  overlap the data line  171 . The first shielding electrode  192   a  and the second shielding electrode  192   b  may be alternately disposed along the first direction. 
     The first shielding electrode  192   a  and the second shielding electrode  192   b  may include the same material as the pixel electrode  191 . The first shielding electrode  192   a  and the second shielding electrode  192   b  may be simultaneously formed in a process forming the pixel electrode  191 , but are not limited thereto. 
     The first shielding electrode  192   a  and the second shielding electrode  192   b  may receive different voltages from each other. According to an exemplary embodiment, the first shielding electrode  192   a  may receive a first voltage that is higher than a voltage applied to the pixel electrode  191 , and the second shielding electrode  192   b  may receive a second voltage that has a same level as or a lower than the voltage applied to the pixel electrode  191 . 
     The vertical stem part  191   b  of the pixel electrode  191  may be positioned to be adjacent to the first shielding electrode  192   a  receiving the higher voltage than the voltage applied to the pixel electrode  191 . One pixel positioned at the right of the first shielding electrode  192   a  with reference to the first shielding electrode  192   a  may include the vertical stem part  191   b  positioned to be adjacent to the first shielding electrode  192   a,  and one pixel positioned at the left of the first shielding electrode  192   a  may also include the vertical stem part  191   b  positioned to be adjacent to the first shielding electrode  192   a.  The shape of the pixel electrodes  191  positioned at the left and the right with reference to the first shielding electrode  192   a  may be symmetrical. 
     Two pixel electrodes  191  positioned between two adjacent second shielding electrodes  192   b  may include four domains where the liquid crystal molecules  31  are arranged in the different directions from each other. Two pixel electrodes  191  positioned at respective sides with reference to the first shielding electrode  192   a  may include four domains Da, Db, Dc, and Dd where the liquid crystal molecules  31  are arranged in the different directions from each other. 
     In detail, the pixel electrode  191  positioned at the right with reference to the first shielding electrode  192   a  may include minute branch parts  191   c  extending in the right/upper direction and minute branch parts  191   c  extending in the right/lower direction. Also, the pixel electrode  191  positioned at the left with reference to the first shielding electrode  192   a  may include minute branch parts  191   c  extending in the left/upper direction and minute branch parts  191   c  extending in the left/lower direction. The liquid crystal layer  3  overlapping two adjacent pixel electrodes  191  may include four domains Da, Db, Dc, and Dd divided depending on the arrangement direction of the liquid crystal molecules  31 . 
     Hereinafter, the movement of the liquid crystal molecules  31  of the above-described display device including the pixel electrode  191  and the shielding electrodes  192   a  and  192   b  will be described. 
     Referring to  FIG. 4 , when the first voltage that is higher than the voltage applied to the pixel electrode  191  is applied to the first shielding electrode  192   a,  a fringe field of a front direction is strongly formed. Accordingly, the liquid crystal molecules  31  positioned between the first shielding electrode  192   a  and the vertical stem part may be arranged in the direction parallel to the liquid crystal molecules  31  arranged by the minute branch parts. The luminance of the display device may be improved through the same arrangement of the liquid crystal molecules  31  on the boundary of the first shielding electrode  192   a  and the pixel electrode  191 . 
     Also, when the second voltage that is lower than the voltage applied to the pixel electrode  191  is applied to the second shielding electrode  192   b,  a fringe field of a reverse direction generated on the boundary between the pixel electrode  191  and the second shielding electrode  192   b  may be weak. As the liquid crystal molecules  31  positioned between the second shielding electrode  192   b  and the pixel electrode  191  are arranged parallel to the liquid crystal molecules  31  arranged by the minute branch parts, the luminance of the display device may be improved. 
     As shown in  FIG. 5 , when the same voltage (as one example, a common voltage) is applied to the first shielding electrode  192   a  and the second shielding electrode  192   b,  the arrangement directions of the liquid crystal molecules  31  positioned between the vertical stem part and the first shielding electrode  192   a  and the liquid crystal molecules  31  overlapping the minute branch part are collapsed such that a dark part may be generated. The luminance of the display device may be reduced by the dark part. 
     According to an exemplary embodiment of the present invention, as the liquid crystal molecules  31  are effectively arranged to the region where the shielding electrodes  192   a  and  192   b  are adjacent (where the arrangement control of the liquid crystal molecules  31  is not easy), as well as the region where the minute branch parts  191   c  are positioned, the display device with improved luminance may be provided. 
     A first alignment layer  11  may be positioned between the pixel electrode  191  and the liquid crystal layer  3  and between the shielding electrodes  192   a  and  192   b  and the liquid crystal layer  3 . 
     The color conversion display panel  300  includes a substrate  310  overlapping the thin film transistor array panel  100 . A light blocking member  320  is positioned between the substrate  310  and the thin film transistor array panel  100 . In detail, the light blocking member  320  is positioned between the substrate  310  and later-described color conversion layers  330 R and  330 G and between the substrate  310  and a later-described transmissive layer  330 B. 
     The light blocking member  320  may be positioned between the red color conversion layer  330 R and the green color conversion layer  330 G, between the green color conversion layer  330 G and the transmissive layer  330 B, and between the transmissive layer  330 B and the red color conversion layer  330 R along the first direction. Also, the light blocking member  320  may be positioned between the red color conversion layer  330 R and the red color conversion layer  330 R adjacent to each other in the second direction, between the green color conversion layer  330 G and the green color conversion layer  330 G adjacent to each other in the second direction, and between the transmissive layer  330 B and the transmissive layer  330 B adjacent to each other in the second direction. The light blocking member  320  may have a lattice shape or a straight line shape in plan view or when view from above. 
     The light blocking member  320  may prevent a mixture of different colors emitted from adjacent pixels and define regions where the red color conversion layer  330 R, the green color conversion layer  330 G, and the transmissive layer  330 B are disposed. The light blocking member  320  may use any material to block (reflect or absorb) the light. 
     A blue light cutting filter  325  may be positioned between the substrate  310  and the light blocking member  320 , and the thin film transistor array panel  100 . The blue light cutting filter  325  may be positioned between the red color conversion layer  330 R and the substrate  310  and between the green color conversion layer  330 G and the substrate  310 . The blue light cutting filter  325  may not overlap a region emitting blue light where the transmissive layer  330 B is positioned. 
     The blue light cutting filter  325  may include a first region overlapping the red color conversion layer  330 R and a second region overlapping the green color conversion layer  330 G, and the regions may be connected to each other. However, it is not limited thereto, and the first region and the second region may be formed to be separated from each other. When the first region and the second region are separated from each other, the separated blue light cutting filters  325  may include different materials from each other. 
     The blue light cutting filter  325  may block blue light supplied from the light unit  500 . The blue light incident from the light unit  500  to the red color conversion layer  330 R and the green color conversion layer  330 G may be converted into red or green light by semiconductor nanocrystals  331 R and  331 G, and some blue light may be emitted as it is without the conversion. The blue light emitted without the conversion is mixed with the red light or the green light, thus the color reproducibility may be deteriorated. The blue light cutting filter  325  may block (absorb or reflect) blue light supplied from the light unit  500  from being emitted through the substrate  310  without being absorbed in the red color conversion layer  330 R and the green color conversion layer  330 G. 
     The blue light cutting filter  325  may include any material capable of obtaining the above-described effects, and as one example, may include a yellow color filter. The blue light cutting filter  325  may have a stacked structure of a single layer or multiple layers. 
     In exemplary embodiments, the blue light cutting filter  325  contacting the substrate  310  is shown, but the present invention is not limited thereto, and a separate buffer layer may be positioned between the substrate  310  and blue light cutting filter  325 . 
     The plurality of the color conversion layers  330 R and  330 G and the transmissive layer  330 B may be positioned between the substrate  310  and the thin film transistor array panel  100 . The plurality of the color conversion layers  330 R and  330 G and the transmissive layer  330 B may be alternately arranged along the first direction. 
     The plurality of the color conversion layers  330 R and  330 G may convert incident light into light having a different wavelength from that of the incident light, and emit the converted light. The plurality of the color conversion layers  330 R and  330 G may include the red color conversion layer  330 R and the green color conversion layer  330 G. The incident light is not converted in the transmissive layer  330 B, and the incident light may be emitted as it is. As an example, blue light may be incident on the transmissive layer  330 B, and may be emitted as it is. 
     The red color conversion layer  330 R may include the first semiconductor nanocrystal  331 R that converts incident blue light into red light. The first semiconductor nanocrystal  331 R may include at least one of a phosphor and a quantum dot. 
     The green color conversion layer  330 G may include the second semiconductor nanocrystal  331 G that coverts incident blue light into green light. The second semiconductor nanocrystal  331 G may include at least one of a phosphor and a quantum dot. 
     The quantum dot included in the first semiconductor nanocrystal  331 R and the second semiconductor nanocrystal  331 G may be independently selected from a Group II-VI compound, a Group III-V compound, a Group IV-VI compound, a Group IV element, a Group IV compound, and a combination thereof. 
     The Group II-VI compound may be a two-element compound selected from CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, and a mixture thereof; a three-element compound selected from CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, and a mixture thereof; and a four-element compound selected from HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, and a mixture thereof. The Group III-V compound may be a two-element compound selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and a mixture thereof; a three-element compound selected from GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, and a mixture thereof; and a four-element compound selected from GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, GaAlNP, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and a mixture thereof. The Group IV-VI compound may be a two-element compound selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe, and a mixture thereof; a three-element compound selected from SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and a mixture thereof; and a four-element compound selected from SnPbSSe, SnPbSeTe, SnPbSTe, and a mixture thereof. The Group IV element may be selected from Si, Ge, and a mixture thereof. The Group IV compound may be a two-element compound selected from SiC, SiGe, and a mixture thereof. 
     In this case, the two-element compound, the three-element compound, or the four-element compound may be present in particles at uniform concentrations, or they may be divided into states having partially different concentrations to be present in the same particle, respectively. In addition, a core/shell structure in which some quantum dots enclose some other quantum dots may be possible. An interface between the core and the shell may have a concentration gradient in which a concentration of elements of the shell decreases closer to its center. 
     The quantum dot may have a full width at half maximum (FWHM) of the light-emitting wavelength spectrum that is equal to or less than about 45 nm, preferably equal to or less than about 40 nm, and more preferably equal to or less than about 30 nm, and in this range, color purity or color reproducibility may be improved. In addition, since light emitted through the quantum dot is emitted in all directions, a viewing angle of light may be improved. 
     When the first semiconductor nanocrystal  331 R includes a red phosphor, the red phosphor may include at least one selected from a group including (Ca, Sr, Ba)S, (Ca, Sr, Ba) 2 Si 5 N 8 , CaAlSiN 3 , CaMoO 4 , and Eu 2 Si 5 N 8 , and but the present disclosure is not limited thereto. 
     When the second semiconductor nanocrystal  331 G includes a green phosphor, the green phosphor may include at least one selected from a group including yttrium aluminum garnet (YAG), (Ca, Sr, Ba) 2 SiO 4 , SrGa 2 S 4 , BAM, α-SiAlON, β-SiAlON, Ca 3 Sc 2 Si 3 O 12 , Tb 3 Al 5 O 12 , BaSiO 4 , CaAlSiON, and (Sr (1−x) Ba x )Si 2 O 2 N 2 , but the present disclosure is not limited thereto. The x may be any number between 0 and 1. 
     The transmissive layer  330 B may pass incident light as it is. The transmissive layer  330 B may include a resin passing blue light. The transmissive layer  330 B positioned at the region emitting the blue light does not include the separate semiconductor nanocrystal, and passes the incident blue as it is. 
     Although not shown, the transmissive layer  330 B may further include at least one of a dye and a pigment. The transmissive layer  330 B including the dye or pigment may reduce the external light reflection, and may provide the blue light with improved color purity. 
     At least one of the red color conversion layer  330 R, the green color conversion layer  330 G, and the transmissive layer  330 B may further include scatterers  332 . Contents of respective scatterers  332  included in the red color conversion layer  330 R, the green color conversion layer  330 G, and the transmissive layer  330 B may be different. 
     The scatterers  332  may increase an amount of light that is converted in or passes through the color conversion layers  330 R and  330 G and the transmissive layer  330 B, and may uniformly provide front luminance and lateral luminance. 
     The scatterer  332  may include any material capable of evenly scattering incident light. As an example, the scatterer  332  may include at least one among TiO 2 , ZrO 2 , Al 2 O 3 , In 2 O 3 , ZnO, SnO 2 , Sb 2 O 3 , and ITO. 
     As one example, the red color conversion layer  330 R, the green color conversion layer  330 G, and the transmissive layer  330 B may include a photosensitive resin, and may be formed through a photolithography process. In addition, they may be formed through a printing process or an inkjet process, and in the case of these processes, the red color conversion layer  330 R, the green color conversion layer  330 G, and the transmissive layer  330 B may include a material that is not the photosensitive resin. In exemplary embodiments, although it is described that the color conversion layer and the transmissive layer are formed through the photolithography process, the printing process, or the inkjet process, the present invention is not limited thereto. 
     A light filter layer  340  is positioned between the color conversion layers  330 R and  330 G and an over-coating layer  350  and between the transmissive layer  330 B and the over-coating layer  350 . 
     The light filter layer  340  may be a filter transmitting light of a predetermined wavelength, and reflecting or absorbing light except for that of the predetermined wavelength. The light filter layer  340  may have a structure in which layers having a high refractive index and layers having a low refractive index are alternately stacked, and may utilize reinforcement and/or destructive interference between these layers to transmit and/or reflect the predetermined wavelength as above-described. 
     The light filter layer  340  may include at least one of TiO 2 , SiN x , SiO y , TiN, AlN, Al 2 O 3 , SnO 2 , WO 3 , and ZrO 2 , and as one example, it may have a structure in which SiN x  and SiO y  are alternately stacked. The x and y may be adjusted according to process conditions for forming the layers as factors for determining a chemical composition ratio in SiN x  and SiO y . 
     In some exemplary embodiments, the light filter layer  340  may be omitted, and it may be replaced with a low refractive layer or the like. 
     The over-coating layer  350  is positioned between the light filter layer  340  and the thin film transistor array panel  100 . The over-coating layer  350  may overlap a front surface of the substrate  310 . 
     The over-coating layer  350  may flatten a surface of one of the red color conversion layer  330 R, the green color conversion layer  330 G, and the transmissive layer  330 B. The over-coating layer  350  includes an organic material, but is not limited thereto, and may include any material having the flattening function. 
     A second polarization layer  22  may be positioned between the over-coating layer  350  and the liquid crystal layer  3 . The second polarization layer  22  may be formed by any method of a deposited polarization layer, a coated polarization layer, and a printed polarization layer. As one example, a wire grid polarizer may be used. When the second polarization layer  22  is the wire grid polarization layer, the second polarization layer  22  may include a plurality of bars having a width of several nanometers. 
     An insulating layer  360 , a common electrode  370 , and a second alignment layer  21  are positioned between the second polarization layer  22  and the liquid crystal layer  3 . 
     The insulating layer  360  as a layer insulating the second polarization layer  22  and the common electrode  370  of the metal material may be omitted when the second polarization layer  22  is not a metal material. The common electrode  370  receiving the common voltage may form an electric field with the above-described pixel electrode  191 . The configuration in which the common electrode  370  is positioned in a different display panel from that of the pixel electrode  191  is described in the exemplary embodiments, but is not limited thereto, and they may be included in the same display panel. 
     The liquid crystal layer  3  is positioned between the thin film transistor array panel  100  and the color conversion display panel  300 , and includes a plurality of liquid crystal molecules  31 . It is possible to control transmittance of the light received from the light unit  500  according to a degree of movement of the liquid crystal molecules  31  and the like. The liquid crystal layer  3  according to an exemplary embodiment may further include a reactive mesogen or a polymer of the reactive mesogen. 
     Next, the display device according to a variation exemplary embodiment of the present invention will be described with reference to  FIG. 6 .  FIG. 6  is a top plan view of a pixel of a display device according to a variation in the exemplary embodiment of  FIG. 2 . The description for the same constituent elements described with reference to  FIG. 2 ,  FIG. 3 , and  FIG. 4  is omitted. 
     Referring to  FIG. 6 , the pixel electrode  191  includes the horizontal stem part  191   a,  the vertical stem part  191   b,  and the minute branch parts  191   c  extending from the horizontal stem part  191   a  and the vertical stem part  191   b  along the diagonal direction. According to an exemplary embodiment, the horizontal stem parts  191   a  may be connected to the end of the vertical stem part  191   b  to be crossed therewith. One pixel electrode  191  may include a plurality of minute branch parts  191   c  extending from the horizontal stem part  191   a  and the vertical stem part  191   b  and elongated in one diagonal direction. 
     The vertical stem part  191   b  of the pixel electrode  191  may be positioned to be adjacent to the first shielding electrode  192   a  receiving the higher voltage than the voltage applied to the pixel electrode  191 . One pixel positioned at the right of the first shielding electrode  192   a  with reference to the first shielding electrode  192   a  may include the vertical stem part  191   b  positioned to be adjacent to the first shielding electrode  192   a,  and one pixel positioned at the left of the first shielding electrode  192   a  may also include the vertical stem part  191   b  positioned to be adjacent to the first shielding electrode  192   a.  The shape of the pixel electrodes  191  positioned at the left and the right with reference to the first shielding electrode  192   a  may be symmetrical. 
     The liquid crystal layer  3  overlapping two pixel electrodes  191  positioned between two adjacent second shielding electrodes  192   b  may include may include two domains where the liquid crystal molecules  31  are arranged in the different directions from each other. In detail, the pixel electrode  191  positioned at the right with reference to the first shielding electrode  192   a  may include the minute branch parts  191   c  extending in the right/upper direction, and the pixel electrode  191  positioned at the left with reference to the first shielding electrode  192   a  may include the minute branch parts  191   c  extending in the left/upper direction. The liquid crystal layer  3  overlapping two adjacent pixel electrodes  191  may include two domains divided depending on the arrangement direction of the liquid crystal molecules  31 . 
     The present specification describes the exemplary embodiment in which the different voltages are applied to the first shielding electrode  192   a  and the second shielding electrode  192   b.  However, it is not limited thereto, and the same voltage may be applied to the first shielding electrode  192   a  and the second shielding electrode  192   b.  In the exemplary embodiment in which the same voltage (as one example, the common voltage) is applied to the first shielding electrode  192   a  and the second shielding electrode  192   b,  a method for controlling the arrangement of the liquid crystal molecules  31  of the initial state in which the voltage is not applied to the pixel electrode  191  and the common electrode  370  is not applied may be used. 
     According to an exemplary embodiment, in the state in which the voltage is not applied to the pixel electrode  191  and the common electrode  370 , the liquid crystal molecules  31  positioned between the first shielding electrode  192   a  and the adjacent vertical stem part  191   b  may be parallel to the arrangement of the liquid crystal molecules  31  overlapping the minute branch parts  191   c.    
     In detail, the liquid crystal layer  3  according to the present invention may include the liquid crystal compound and the reactive mesogen. The display device may be manufactured by a method of combining the thin film transistor array panel  100  and the color conversion display panel  300  after dripping the liquid crystal material on the thin film transistor array panel  100  or the color conversion display panel  300 . 
     In the state in which the voltage is applied to the pixel electrode  191  and the common electrode  370  after the combination, an electric field exposure process irradiating light such as ultraviolet rays (UV) is executed. Thus, while the reactive mesogen included in the dripped liquid crystal material moves to the side of the thin film transistor array panel  100  or the color conversion display panel  300 , a protrusion including an alignment polymer may be formed. The protrusion may have the pretilt in the direction parallel to the length direction of the minute branch part  191   c  of the pixel electrode  191  for the liquid crystal molecules  31 . 
     In the electric field exposure process, the first voltage that is higher than the voltage applied to the pixel electrode  191  may be applied to the first shielding electrode  192   a,  and the second voltage that is lower than or the same level as the voltage applied to the pixel electrode  191  may be applied to the second shielding electrode  192   b.  Accordingly, as shown in  FIG. 4 , the initial state in which the arrangement directions of the liquid crystal molecules  31  between the first shielding electrode  192   a  and the vertical stem part  191   b,  between the second shielding electrode  192   b  and the pixel electrode  191 , and overlapping the minute branch parts  191   c  are parallel may be provided. 
     Any configuration for applying the first voltage to the first shielding electrode  192   a  and the second voltage to the second shielding electrode  192   b  In the electric field exposure process, and the same voltage to the first shielding electrode  192   a  and the second shielding electrode  192   b  during the driving of the display device, is of course possible. As one example, the substrate  110  includes a pad part applying the same voltage to the first shielding electrode  192   a  and the second shielding electrode  192   b,  and a configuration in which a pad part for applying another voltage to the first shielding electrode  192   a  and the second shielding electrode  192   b  extends outside the substrate  110  during the manufacturing process and is removed after the manufacturing of the display device is possible. 
     According to the above-described exemplary embodiment, even if the same voltage is applied to the first shielding electrode  192   a  and the second shielding electrode  192   b  during the driving of the display device, the luminance reduction due to the generation of the dark part by the initial state of the liquid crystal molecules  31  may be prevented. 
     Next, a luminance degree of one pixel according to a comparative example and an exemplary embodiment will be described with reference to  FIG. 7 .  FIG. 7  is a luminance simulation image of a pixel according to Comparative Example 1, Comparative Example 2, Comparative Example 3, Exemplary Embodiment 1, and Exemplary Embodiment 2. 
     Referring to  FIG. 7 , Comparative Example 1 is a display device in which the shielding electrode does not exist and the liquid crystal layer overlapping one pixel electrode includes four domains having the different arrangement directions of the liquid crystal molecules. Comparative Example 2 is a display device in which a frame of the pixel electrode has a bound shape and other conditions are the same as Comparative Example 1. Comparative Example 3 is a display device in which the liquid crystal layer overlapping one pixel electrode includes two domains. Exemplary Embodiment 1 is a display device in which the liquid crystal layer overlapping one pixel electrode includes two domains and the first shielding electrode and the second shielding electrode are included according to an exemplary embodiment. Exemplary Embodiment 2 is a display device in which the liquid crystal layer overlapping one pixel electrode includes one domain and the first shielding electrode and the second shielding electrode are included. 
     As a result of examining the luminance for these, Comparative Example 1 represents about 97% luminance, Comparative Example 2 represents about 100% luminance, and Comparative Example 3 represents 101.4% luminance. Also, Exemplary Embodiment 1 represents about 106.5% luminance, and Exemplary Embodiment 2 represents about 106.7% luminance. Thus, a display device according to an exemplary embodiment has luminance that is improved by about 6% or more compared with the comparative examples. 
     According to exemplary embodiments, a display device with improved color reproducibility and luminance may be provided. 
     Although certain exemplary embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concepts are not limited to such embodiments, but rather to the broader scope of the appended claims and various obvious modifications and equivalent arrangements as would be apparent to a person of ordinary skill in the art.