Display device

Abstract

A display device is provided, the display device comprising: a light source member including a plurality of light emitting units emitting a first color light; an optical member disposed on an upper side of the light source member; and a liquid crystal display panel disposed on an upper side of the optical member. The optical member comprises: a base substrate; a color conversion layer disposed on the base substrate and including quantum dots for converting the first color light into a second color light and a third color light; a filter layer disposed between the base substrate and the color conversion layer and transmitting the first color light and reflecting the second color light and the third color light; and an optical path changing layer disposed on at least one of an upper surface and a lower surface of the filter layer.

Description

[0001] This application claims priority to and the benefit of Korean Patent Application No. 10-2018-0156956, filed on Dec. 7, 2018, which is hereby incorporated by reference for all purposes as if fully set forth herein. Technical Field

[0002] Exemplary embodiments of the invention relate generally to a display device, and more particularly, to a liquid crystal display device having an optical layer with quantum dots. Background Art

[0003] Various types of display devices are used to provide image information, and liquid crystal displays are widely used in large display devices and portable display devices due to their low power consumption.

[0004] The liquid crystal display device generates an image using light provided from a backlight unit, and the backlight unit includes a plurality of light emitting units for emitting light. On the other hand, in order to improve the light efficiency of the light provided from the light emitting units and to improve the color reproducibility of the liquid crystal display, various types of optical components are added to the lower side of the display panel.

[0005] The above information disclosed in this Background section is only for understanding the background of the inventive concept and therefore it may contain information that does not constitute the prior art. Summary of the invention

[0006] Exemplary embodiments of the present invention provide improvement in display quality of a display device including a direct type light source member.

[0007] Exemplary embodiments of the present invention also provide a display device capable of improving display quality degradation caused by a light emitting element that is selectively turned on and off.

[0008] 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.

[0009] An exemplary embodiment of the present invention provides a display device, which includes: a light source member including a plurality of light emitting units emitting a first color light; an optical member disposed on an upper side of the light source member; and a liquid crystal display panel disposed on an upper side of the optical member. The optical member includes: a base substrate; a color conversion layer disposed on the base substrate and including quantum dots for converting the first color light into a second color light and a third color light; a filter layer disposed between the base substrate and the color conversion layer and transmitting the first color light and reflecting the second color light and the third color light; and an optical path changing layer disposed on at least one of an upper surface and a lower surface of the filter layer.

[0010] The plurality of light emitting units may include: a circuit board; and a plurality of light emitting elements disposed on the circuit board and turned on and off independently of each other.

[0011] The optical path changing layer may be directly disposed on the upper surface or the lower surface of the filter layer.

[0012] The optical path changing layer may be a low refractive layer having a refractive index smaller than that of the color conversion layer.

[0013] The low-refractive layer may include a low-refractive index material including at least one of voids, hollow inorganic particles, porous silica particles, and siloxane polymers.

[0014] The low refractive layer may be a metal layer formed of a metal material such as Ag, Al, Cu or Au or an alloy of the metal material, wherein the thickness of the metal layer may be greater than or equal to and is less than or equal to

[0015] The metal layer may be a single layer.

[0016] The optical path changing layer may be a pattern layer including a plurality of protrusions.

[0017] The protrusions may protrude from the base substrate toward the color conversion layer.

[0018] The filter layer may include: a plurality of first insulating films; and a plurality of second insulating films arranged alternately with the first insulating films. The refractive indexes of the first insulating films and the second insulating films may be different from each other.

[0019] The refractive index of the first insulating film may be greater than or equal to 1.4 and less than or equal to 1.6. The refractive index of the second insulating film may be greater than or equal to 1.9 and less than or equal to 2.1.

[0020] The optical member may further include a barrier layer disposed on at least one of an upper surface and a lower surface of the color conversion layer.

[0021] The optical member may further include a scattering layer disposed on an upper side or a lower side of the color conversion layer.

[0022] The scattering layer may include TiO 2 、SiO 2 、ZnO、Al 2 O 3 ,BaSO 4 、CaCO 3 and ZrO 2 At least one of the scattering particles.

[0023] The center wavelength of the first color light may be in the range of 420 nm to 470 nm (inclusive). The center wavelength of the second color light may be in the range of 520 nm to 570 nm (inclusive). The center wavelength of the third color light may be in the range of 620 nm to 670 nm (inclusive).

[0024] Another exemplary embodiment of the present invention provides a display device, which includes: a light source member including a plurality of light emitting units; an optical member disposed on an upper side of the light source member; and a liquid crystal display panel disposed on an upper side of the optical member. The optical member includes: a base substrate; a color conversion layer disposed on the base substrate and including quantum dots; a filter layer disposed between the base substrate and the color conversion layer and configured to transmit light having a central wavelength in a range of 420nm to 470nm (including 420nm and 470nm) among incident light, and reflect light having a central wavelength in a range of 520nm to 670nm (including 520nm and 670nm); and an optical path changing layer disposed on at least one of an upper surface and a lower surface of the filter layer.

[0025] The filter layer may reflect 80% or more of light having a central wavelength within a range of 520 nm to 670 nm inclusive, among light incident in a normal direction of the upper surface or the lower surface.

[0026] The optical path changing layer may be a low refractive layer or a pattern layer, the low refractive layer having a refractive index greater than or equal to 0.1 and less than or equal to 1.4, and the pattern layer including a plurality of protrusions.

[0027] Another exemplary embodiment of the present invention also provides a display device, which includes: an optical member; a light source member, which is disposed on the lower side of the optical member and includes a plurality of light emitting units for providing blue light to the optical member; and a liquid crystal display panel, which is disposed on the upper side of the optical member. The optical member includes: a base substrate; a color conversion layer, which is disposed on the base substrate and includes a first quantum dot excited by the blue light to emit green light and a second quantum dot excited by the blue light to emit red light; a filter layer, which is disposed between the base substrate and the color conversion layer to transmit the blue light and reflect the green light and the red light; and an optical path changing layer, which is directly disposed on at least one of the upper surface and the lower surface of the filter layer.

[0028] The optical path changing layer may be a low refractive layer having a refractive index smaller than that of the color conversion layer or a pattern layer including a plurality of protrusions protruding from the base substrate toward the color conversion layer.

[0029] 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

[0030] 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 concept.

[0031] Figure 1 is a perspective view of a display device of an exemplary embodiment of the inventive concept.

[0032] Figure 2 It shows Figure 1 1 is a plan view of a portion of a display device of an exemplary embodiment shown in FIG.

[0033] Figure 3 is an equivalent circuit diagram of a light emitting unit according to an exemplary embodiment of the inventive concept.

[0034] Figure 4 is a cross-sectional view illustrating an exemplary embodiment of a light emitting unit included in a light source member.

[0035] Figure 5 is a cross-sectional view illustrating a display device according to an exemplary embodiment of the inventive concept.

[0036] Figure 6 is a cross-sectional view illustrating a color conversion layer according to an exemplary embodiment of the inventive concept.

[0037] Fig. 7A is a cross-sectional view of a filter layer according to an exemplary embodiment of the inventive concept.

[0038] Figure 7B is a graph illustrating optical characteristics of a filter layer according to an exemplary embodiment of the inventive concept.

[0039] Figure 8 is a cross-sectional view illustrating a low-refractive layer according to an exemplary embodiment of the inventive concept.

[0040] Fig. 9 is a cross-sectional view schematically showing a light path in a conventional display device.

[0041] Fig.10 is a cross-sectional view schematically illustrating a light path in a display device according to an exemplary embodiment of the inventive concept.

[0042] Fig.11A is a cross-sectional view illustrating an optical member according to an exemplary embodiment of the inventive concept.

[0043] Fig. 11B is a cross-sectional view illustrating an optical member according to an exemplary embodiment of the inventive concept.

[0044] Fig. 12A is a cross-sectional view illustrating an optical member according to an exemplary embodiment of the inventive concept.

[0045] Fig. 12B is a cross-sectional view illustrating a color conversion layer according to an exemplary embodiment of the inventive concept.

[0046] Fig.13A is a cross-sectional view illustrating an optical member according to an exemplary embodiment of the inventive concept.

[0047] Fig. 13B is a cross-sectional view illustrating an optical member according to an exemplary embodiment of the inventive concept.

[0048] Fig.14 is a cross-sectional view schematically illustrating a light path in a display device according to an exemplary embodiment of the inventive concept. DETAILED DESCRIPTION

[0049] In the following description, for the purpose of explanation, many specific details are set forth to provide a thorough understanding of various exemplary embodiments of the invention. As used herein, an "embodiment" is a non-limiting example of a device or method using one or more inventive concepts disclosed herein. However, it is apparent that various exemplary embodiments may be practiced without these specific details or using one or more equivalent arrangements. In other cases, well-known structures and devices are shown in block diagram form to avoid unnecessarily obscuring various exemplary embodiments. In addition, various exemplary embodiments may be different, but need not be exclusive. For example, without departing from the inventive concept, the specific shape, construction, and characteristics of an exemplary embodiment may be used or implemented in another exemplary embodiment.

[0050] Unless otherwise stated, the exemplary embodiments shown should be understood as providing exemplary features of different details of some ways in which the inventive concept can be implemented in practice. Therefore, unless otherwise stated, the features, components, modules, layers, films, panels, regions and / or aspects, etc. (hereinafter individually or collectively referred to as "elements") of various embodiments may be further combined, separated, interchanged and / or rearranged without departing from the inventive concept.

[0051] The use of cross-hatching and / or shading in the drawings is generally provided to clarify the boundaries between adjacent elements. Therefore, unless otherwise specified, the presence or absence of cross-hatching or shading does not express or indicate any preference or requirement for the specific material, material properties, size, ratio, commonality between the elements shown, and / or any other characteristics, attributes, performance, etc. of the elements. In addition, in the drawings, the size and relative size of the elements may be exaggerated for the purpose of clarity and / or description. When the exemplary embodiments can be implemented differently, the specific process sequence can be performed differently from the described sequence. For example, two continuously described processes can be performed substantially simultaneously or in an order opposite to the described sequence. In addition, the same reference numerals represent the same elements.

[0052] When an element, such as a layer, is referred to as being "on," "connected to," or "bonded to" another element or layer, it may be directly on, directly connected to, or directly bonded to the other element or layer, or there may be intervening elements or layers. However, when an element or layer is referred to as being "directly on," "directly connected to," or "directly bonded to" another element or layer, there are no intervening elements or layers. For this purpose, the term "connected" may refer to a physical connection, an electrical connection, and / or a fluid connection with or without intervening elements. In addition, the DR1 axis, the DR2 axis, and the DR3 axis are not limited to the three axes of a rectangular coordinate system, such as the x-axis, the y-axis, and the z-axis, and may be interpreted in a broader sense. For example, the DR1 axis, the DR2 axis, and the DR3 axis may be perpendicular to each other, or may represent different directions that are not perpendicular to each other. For the purpose 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 interpreted as only X, only Y, only Z, or any combination of two or more of X, Y, and Z, such as XYZ, XYY, YZ, and ZZ for example. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0053] 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. Therefore, without departing from the disclosed teachings, the first element discussed below may be referred to as the second element.

[0054] For descriptive purposes, spatially relative terms such as "under," "below," "below," "above," "above," "higher," "side" (e.g., as in "sidewall"), etc., may be used herein to describe the relationship of one element to another (other) element as shown in the accompanying drawings. In addition to the orientation depicted in the accompanying drawings, the spatially relative terms are intended to encompass different orientations of the device in use, operation, and / or manufacture. For example, if the device in the accompanying drawings is turned over, an element described as "under" or "beneath" other elements or features would subsequently be oriented to be "above" the other elements or features. Thus, the exemplary term "under" can include both above and below orientations. In addition, the device may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein are therefore interpreted accordingly.

[0055] The terms used here are for the purpose of describing specific embodiments, and are not intended to be limiting. As used here, unless the context clearly indicates otherwise, the singular forms "one", "an" and "the (the)" are also intended to include plural forms. In addition, when the terms "include", "comprising" and / or its variations are used in this specification, it is explained that there are the features, integral bodies, steps, operations, elements, components and / or their groups, but it is not excluded that there are or add one or more other features, integral bodies, steps, operations, elements, components and / or their groups. It is also noted that, as used here, the terms "substantially", "approximately" and other similar terms are used as approximate terms and not as degree terms, and are therefore used to explain the inherent deviations in the measured values, calculated values ​​and / or provided values ​​that will be recognized by those of ordinary skill in the art.

[0056] Various exemplary embodiments are described herein with reference to cross-sectional views and / or exploded views as schematic diagrams of idealized exemplary embodiments and / or intermediate structures. Therefore, variations in the shapes of the diagrams caused by, for example, manufacturing techniques and / or tolerances are expected. Therefore, the exemplary embodiments disclosed herein should not necessarily be interpreted as being limited to the specific illustrated shapes of the regions, but rather include deviations in shapes caused by, for example, manufacturing. In this way, the regions shown in the drawings may be schematic in nature, and the shapes of these regions may not reflect the actual shapes of the regions of the device, and therefore are not necessarily intended to be limiting.

[0057] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which this disclosure is a part. Terms (such as those defined in general dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense unless explicitly so defined herein.

[0058] Figure 1 is an exploded perspective view of a display device DD according to an exemplary embodiment of the inventive concept. Figure 2 is a plan view illustrating a portion of a display device DD according to an exemplary embodiment of the inventive concept. Figure 3 is an equivalent circuit diagram of a light emitting unit LU according to an exemplary embodiment of the inventive concept. Figure 4 is a cross-sectional view of a light emitting unit LU according to an exemplary embodiment of the inventive concept. Figure 5 is shown with Figure 1 2 is a cross-sectional view of a portion corresponding to line II′ in a display device DD of the exemplary embodiment shown in FIG.

[0059] Reference Figures 1 to 5 , the display device DD of the exemplary embodiment of the inventive concept may include a light source member LM and a liquid crystal display panel DP disposed on the light source member LM. The optical member OM may be disposed between the light source member LM and the liquid crystal display panel DP. That is, the display device DD may include the light source member LM, the optical member OM, and the liquid crystal display panel DP sequentially stacked in the direction of the third directional axis DR3.

[0060] The first direction axis DR1 to the third direction axis DR3 are Figure 1 , and the direction axes described here are relative. Figure 1 In the embodiment, the direction of the third direction axis DR3 may be defined as a direction along which an image is provided to a user. In addition, the first direction axis DR1 and the second direction axis DR2 are orthogonal to each other, and the third direction axis DR3 may be a normal direction of a plane defined by the first direction axis DR1 and the second direction axis DR2.

[0061] The front surface (or upper surface, top surface) and the rear surface (or lower surface, bottom surface) of each member or unit described below are separated by a third directional axis DR3. However, the first directional axis to the third directional axis DR1, DR2 and DR3 shown in this exemplary embodiment are merely illustrative. Hereinafter, the first direction to the third direction are defined as directions represented by the first directional axis to the third directional axis DR1, DR2 and DR3, respectively, and refer to the same figure marks.

[0062] In the display device DD of this exemplary embodiment, the liquid crystal display panel DP may be overlapped with the light source member LM. The liquid crystal display panel DP is disposed on the upper side of the light source member LM, and the display device DD may be a display device having the light source member LM as a direct light source. In addition, an optical member OM may be disposed between the light source member LM and the liquid crystal display panel DP to overlap with the light source member LM and the liquid crystal display panel DP. The optical member OM may convert light emitted from the light source member LM and transmit the converted light to the liquid crystal display panel DP. The optical member OM may include a color conversion layer CCL.

[0063] The display device DD may include a bottom cover BC. The bottom cover BC disposed on the lower side of the light source member LM may be used to accommodate the light source member LM, the optical member OM, and the liquid crystal display panel DP. The bottom cover BC may include a bottom BC-B and a side wall portion BC-S bent and extended from the bottom BC-B. The bottom cover BC may be made of metal or plastic.

[0064] On the other hand, the housing HAU may be disposed on the upper side of the liquid crystal display panel DP. In the display device DD of this exemplary embodiment, the bottom cover BC and the housing HAU are combined with each other to accommodate the liquid crystal display panel DP, the optical member OM and the light source member LM. The housing HAU may be made of metal or plastic.

[0065] The housing HAU may be disposed on the upper side of the liquid crystal display panel DP to cover an edge region of the liquid crystal display panel DP. The housing HAU may include an opening portion HAU-OP in which an image is provided. The housing HAU may be a rectangular frame in a plane. The housing HAU may include a housing side wall portion HAU-S and a front portion HAU-T bent from the housing side wall portion HAU-S. The front portion HAU-T may be omitted in other exemplary embodiments.

[0066] A molding member (not shown) may also be disposed between the bottom cover BC and the housing HAU. The molding member (not shown) may support the liquid crystal display panel DP, etc., such that the liquid crystal display panel DP is spaced apart from the light source member LM at a predetermined interval.

[0067] In such Figure 5 In the display device DD of the exemplary embodiment shown in , the liquid crystal display panel DP includes a first substrate SUB1, a second substrate SUB2 facing the first substrate SUB1, and a liquid crystal layer LCL disposed between the first substrate SUB1 and the second substrate SUB2. The liquid crystal display panel DP may be divided into a display area and a frame area surrounding the display area. The display area is an area where an image is displayed on a plane, and the frame area is an area adjacent to the display area on a plane and where no image is displayed. The liquid crystal display panel DP may include a plurality of pixels disposed in the display area.

[0068] The pixel circuit of the signal line and the pixel is formed on any one of the first substrate SUB1 and the second substrate SUB2 (hereinafter, the array substrate). The array substrate may be connected to the main circuit substrate through a chip on film (COF) or the like. A central control circuit for driving the liquid crystal display panel DP may be provided on the main circuit board. The central control circuit may be a microprocessor. The chip of the COF may be a data drive circuit. The gate drive circuit may be mounted on the array substrate, or may be integrated on the array substrate in the form of low temperature polysilicon (LTPS).

[0069] The central control circuit may control the light emitting unit LU. A control signal for controlling the light emitting unit LU may be sent to a dimming circuit of the light emitting unit LU.

[0070] The light source member LM may be disposed on the lower side of the liquid crystal display panel DP. The light source member LM may be disposed on the bottom BC-B of the bottom cover BC. The light source member LM may include a plurality of light emitting units LU and a reflective plate RF. The plurality of light emitting units LU may be disposed on the upper portion of the reflective plate RF. The light emitting unit LU is disposed on the lower side of the liquid crystal display panel DP and the optical member OM.

[0071] Each light emitting unit LU may include a plurality of light emitting elements LD forming a point light source and a circuit board FB providing electrical signals to the light emitting elements LD. Each of the plurality of light emitting elements LD may include a light emitting diode LED. The light emitting unit LU may include a different number of light emitting elements LD.

[0072] On the other hand, despite Figure 1 and Figure 2 The light emitting elements LD are shown to be spaced and arranged at regular intervals, but the inventive concept is not limited thereto. The arrangement interval of the light emitting elements LD may vary according to the position corresponding to the central area or edge area of ​​the liquid crystal display panel DP, etc. In different light emitting units LU, the arrangement interval of the light emitting elements LD may be different.

[0073] The light emitting element LD may be a light emitting element that receives an electrical signal from a circuit board FB to emit light. Although not shown separately, the display device DD may further include a connecting circuit board (not shown) that electrically connects the light emitting units LU to each other. A dimming circuit may be provided on the connecting circuit board (not shown). The dimming circuit may dim the light emitting unit LU based on a control signal received from a central control circuit. In an exemplary embodiment, the light emitting element LD may be turned on and off independently of each other. That is, a plurality of light emitting elements LD included in one light emitting unit LU may be turned on and off independently. For example, one light emitting unit LU may include a light emitting element that is turned on, and also includes a light emitting element that is turned off and disposed adjacent to the light emitting element that is turned on. In addition, a plurality of light emitting elements LD included in one light emitting unit LU may be dimmed independently of each other. As Figure 3 As shown in FIG. 1 , the light emitting element LD is connected to the corresponding signal line LU-S so as to be dimmable. Figure 2 and Figure 3 As shown in , the circuit board FB may have a shape extending in the first direction axis DR1.

[0074] Figure 4 is a cross-sectional view showing an exemplary embodiment of a light emitting unit LU. Figure 4 , the light emitting element LD included in the light emitting unit LU may include a light emitting diode LED, a pair of lead frames LF1 and LF2 , and a body part BD.

[0075] The light emitting diode LED generates light in response to a voltage supplied from the circuit board FB. The light emitting diode LED has a structure in which an n-type semiconductor layer, an active layer, and a p-type semiconductor layer are sequentially stacked, and when a driving voltage is applied, electrons and holes can recombine while moving and can generate light.

[0076] The body part BD may mount the light emitting diode LED and fix the first lead frame LF1 and the second lead frame LF2. The body part BD may be made of a material such as a polymer resin. In addition, the body part BD may have a cavity CV, and the cavity CV may be a space in which the light emitting diode LED is mounted.

[0077] The light emitting diode LED may be disposed in the cavity CV of the body portion BD, and a sealing portion SR surrounding and filling the light emitting diode LED may be disposed in the cavity CV. The sealing portion SR may be used to protect the light emitting diode LED. The sealing portion SR may be filled with a filling resin including epoxy resin or acrylic resin.

[0078] In addition, each of the first lead frame LF1 and the second lead frame LF2 may penetrate a portion of the body portion BD. In addition, the lead frames LF1 and LF2 exposed in the cavity CV and the light emitting diode LED may be electrically connected through the connection leads WL1 and WL2.

[0079] In an exemplary embodiment, the light emitting element LD may be a light emitting element that emits a first color light. That is, the light emitting unit LU may emit a first color light. The first color light may have a central wavelength within a wavelength range of 420 nm to 470 nm (including 420 nm and 470 nm). The first color light may be a typical blue light.

[0080] On the other hand, the shape of the light emitting unit LU is not limited to Figure 4 , and for example, the sealing portion SR or the like may be provided to surround the light emitting diode LED in a lens shape. In this case, the light emitting element LD may not include a separate body portion BD.

[0081] The first color light provided from the light emitting unit LU may be provided to the liquid crystal display panel DP as white light through the color conversion layer CCL to be described later. In other words, by combining the light emitting element LD of the light source member LM and the quantum dot QD contained in the color conversion layer CCL (see Figure 6 ), the light provided from the light source member LM can be finally provided to the liquid crystal display panel DP as white light.

[0082] Refer again Figure 1 , the light source member LM may further include a reflective plate RF. The reflective plate RF may be disposed on the bottom BC-B of the bottom cover BC and cover the entire bottom BC-B. However, the inventive concept is not limited thereto, and the reflective plate RF may not overlap with the light emitting unit LU. For example, the reflective plate RF may be disposed on the bottom BC-B of the bottom cover BC between the light emitting units LU.

[0083] The reflective plate RF may include a reflective film or a reflective coating layer. The reflective plate RF may reflect light provided toward the bottom BC-B of the bottom cover BC and allow the reflected light to enter the inside of the optical member OM again.

[0084] Reference Figure 5 , the optical member OM in the display device DD may include a base substrate BS, a color conversion layer CCL disposed on the base substrate BS, a filter layer FL disposed between the base substrate BS and the color conversion layer CCL, and an optical path changing layer. In the display device DD of this exemplary embodiment, the optical path changing layer may be a low refractive layer LRL or a pattern layer OPL (see Fig.14 ).

[0085] The optical member OM may be used to transmit or wavelength-convert light provided by the light emitting unit LU of the light source member LM and transmit the light to the liquid crystal display panel DP. In addition, in order to effectively transmit the light provided from the light emitting unit LU to the liquid crystal display panel DP, the optical member OM may include a plurality of optical functional layers.

[0086] The optical member OM is disposed on the light source member LM, and a lower surface BS-B of the base substrate BS as a lower side surface of the optical member OM is spaced apart from the light emitting unit LU at a predetermined interval. Light provided from the light emitting unit LU may be incident on the lower surface BS-B of the base substrate BS.

[0087] The base substrate BS of the optical member OM may be made of glass. However, the inventive concept is not limited thereto. The base substrate BS may be made of a polymer resin, and may be formed to include, for example, an acrylic resin, etc. The base substrate BS may be used as a substrate provided with a color conversion layer CCL, a filter layer FL, a low refractive layer LRL, a pattern layer OPL (see FIG. 1 ), which are optical functional layers described later. Fig.14) or scattering layer SL (see Fig.11A ) at the substrate.

[0088] In exemplary embodiments, the color conversion layer CCL may be disposed on an upper side of the base substrate BS. Figure 6 2 is a cross-sectional view showing a color conversion layer CCL in an exemplary embodiment. The color conversion layer CCL may include a base resin BR and quantum dots QD. The quantum dots QD may be dispersed in the base resin BR.

[0089] The matrix resin BR is a medium in which quantum dots QD are dispersed, and can be made of various resin components that can be generally referred to as adhesives. However, the inventive concept is not limited to this, and the medium capable of dispersing quantum dots QD in this specification can be referred to as the matrix resin BR regardless of its name, other functions attached, constituent materials, etc. The matrix resin BR can be a polymer resin. For example, the matrix resin BR can be an acrylic resin, a polyurethane resin, a silicone resin, an epoxy resin, etc. The matrix resin BR can be a transparent resin.

[0090] Quantum dots QD can be changed from light emitting units LU (see Figure 5 ) particles of the wavelength of light provided. Quantum dot QD is a material with a crystal structure of a few nanometers in size and is composed of hundreds to thousands of atoms, and exhibits a quantum confinement effect in which the energy band gap increases due to the small size. When light with a wavelength of energy higher than the band gap is incident on the quantum dot QD, the quantum dot QD absorbs the light and becomes an excited state, and falls to the ground state while emitting light of a specific wavelength. The wavelength of the emitted light has a value corresponding to the band gap. When the size and composition of the quantum dot QD are adjusted, the quantum dot QD can adjust the luminescence characteristics of the quantum confinement effect. The quantum dot QD can be selected from II-VI group compounds, III-V group compounds, IV-VI group compounds, IV group elements, IV group compounds, and combinations thereof.

[0091] The II-VI group compound can be selected from the binary element compound selected from the group consisting of CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS and mixtures thereof; from the binary element compound selected from the group consisting of CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, Cd Ternary element compounds selected from the group consisting of HgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS and mixtures thereof; and quaternary element compounds selected from the group consisting of HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe and mixtures thereof.

[0092] The III-V group compounds can be selected from binary element compounds selected from the group consisting of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb and mixtures thereof; ternary element compounds selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb and mixtures thereof; and quaternary element compounds selected from the group consisting of GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb and mixtures thereof.

[0093] The IV-VI group compound can be selected from a binary element compound selected from the group consisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe and mixtures thereof; a ternary element compound selected from the group consisting of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe and mixtures thereof; and a quaternary element compound selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe and mixtures thereof. The IV group element can be selected from the group consisting of Si, Ge and mixtures thereof. The IV group compound can be a binary element compound selected from the group consisting of SiC, SiGe and mixtures thereof.

[0094] At this time, the binary element compound, the ternary element compound, or the quaternary element compound may exist in the particle at a uniform concentration, or may exist in the same particle by dividing the concentration distribution into a locally different state.

[0095] The quantum dot QD may have a core-shell structure including a core and a shell surrounding the core. In addition, one quantum dot QD may have a core / shell structure surrounding other quantum dots QD. The interface between the core and the shell may have a concentration gradient that decreases as the concentration of the element in the shell approaches the center.

[0096] The quantum dot QD may be a particle having a nanometer size. The quantum dot QD may have a full width half maximum (FWHM) of about 45 nm or less (preferably, about 40 nm or less, more preferably, about 30 nm or less) of the emission wavelength spectrum, and within this range, color purity and color reproducibility may be improved. In addition, since the light emitted by the quantum dot QD is emitted in all directions, the wide viewing angle may be improved.

[0097] The shape of quantum dots QD is not particularly limited as long as it is a form commonly used in the art, and more specifically, quantum dots QD can be in the form of spherical, pyramidal, multi-arm or cubic nanoparticles, nanotubes, nanowires, nanofibers, nanoplate-like particles, etc.

[0098] In an exemplary embodiment, the color conversion layer CCL may include a plurality of quantum dots QD that convert incident light into colors within different wavelength ranges. Figure 6 The color conversion layer CCL includes, for example, a first quantum dot QD1 and a second quantum dot QD2, the first quantum dot QD1 being used to convert incident light of a specific wavelength into light of a first wavelength and emit light of the first wavelength, and the second quantum dot QD2 being used to convert incident light of a specific wavelength into light of a second wavelength and emit light of the second wavelength. The first quantum dot QD1 will be emitted by the light emitting unit LU (see Figure 5) is converted into a second color light, and the second quantum dot QD2 is emitted by the light emitting unit LU (see Figure 5 ) converts the first color light provided into a third color light.

[0099] For example, when the light emitting unit LU (see Figure 5 ) is light in the blue wavelength range, the first quantum dot QD1 can convert the blue light into light of green wavelength, and the second quantum dot QD2 can convert the blue light into light of red wavelength. Figure 5 ) is blue light with a maximum emission peak (or center wavelength) of 420nm to 470nm, the first quantum dot QD1 emits green light with a maximum emission peak (or center wavelength) of 520nm to 570nm, and the second quantum dot QD2 can emit red light with a maximum emission peak (or center wavelength) of 620nm to 670nm. However, blue light, green light, and red light are not limited to the examples of wavelength ranges shown above, and it should be understood that the inventive concept includes all wavelength ranges that can be identified as blue light, green light, and red light.

[0100] Regarding quantum dots QD, the color of the emitted light may change according to the particle size, and the particle size of the first quantum dot QD1 and the particle size of the second quantum dot QD2 may be different from each other. For example, the particle size of the first quantum dot QD1 may be smaller than the particle size of the second quantum dot QD2. At this time, the first quantum dot QD1 may emit light having a wavelength shorter than the wavelength of the light emitted by the second quantum dot QD2.

[0101] Refer again Figure 5 , the color conversion layer CCL can be formed by coating on the base substrate BS. The color conversion layer CCL can be disposed on the base substrate BS using various methods such as slit coating, spin coating, roller coating, spray coating, and inkjet printing. The color conversion layer CCL can be coated on the layer described by the filter layer FL or the low reflection layer LRL or the pattern layer OPL as the optical path changing layer, and can be formed.

[0102] The barrier layers BL1 and BL2 may be disposed on the color conversion layer CCL. The barrier layers BL1 and BL2 may be disposed on at least one of the upper surface and the lower surface of the color conversion layer CCL. In addition, unlike what is shown in the drawings, the barrier layers BL1 and BL2 may be omitted. The barrier layers BL1 and BL2 may be disposed on only one of the upper surface and the lower surface of the color conversion layer CCL. For example, if the inorganic layer is disposed on the upper surface or the lower surface of the color conversion layer CCL, the barrier layers BL1 and BL2 may be omitted.

[0103] although Figure 5It is shown that the barrier layers BL1 and BL2 are disposed on the upper and lower surfaces of the color conversion layer CCL, but the barrier layers BL1 and BL2 may also be disposed on the side surfaces of the color conversion layer CCL. For example, the barrier layers BL1 and BL2 may cover the color conversion layer CCL.

[0104] The barrier layers BL1 and BL2 are used to prevent the penetration of moisture and / or oxygen. The barrier layers BL1 and BL2 may include at least one inorganic layer. That is, the barrier layers BL1 and BL2 may include inorganic materials. For example, the barrier layers BL1 and BL2 may include silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, silicon oxynitride or metal film with fixed transmittance. On the other hand, the barrier layers BL1 and BL2 may also include an organic film. The barrier layers BL1 and BL2 may be composed of a single layer or multiple layers.

[0105] In an exemplary embodiment, the optical member OM includes a filter layer FL. The filter layer FL may be disposed on the lower side of the color conversion layer CCL. For example, the filter layer FL may be directly disposed on the base substrate BS. The filter layer FL may be coated on the upper surface BS-T of the base substrate BS and disposed, or may be deposited and disposed.

[0106] The filter layer FL can transmit the first color light and reflect the second color light and the third color light in a wavelength range different from the wavelength range of the first color light. That is, the filter layer FL can be a selective transflective layer. For example, the filter layer FL can transmit blue light and reflect red light and green light.

[0107] The filter layer FL may mainly transmit light having a central wavelength in the range of 420 nm to 470 nm (inclusive), and mainly reflect light having a central wavelength in the range of 520 nm to 670 nm (inclusive). For example, the filter layer FL may transmit 80% or more of light having a central wavelength in the range of 420 nm to 470 nm (inclusive), and reflect 80% or more of light having a central wavelength in the range of 520 nm to 670 nm (inclusive).

[0108] The filter layer FL reflects a portion of the incident light and provides the reflected light to the liquid crystal display panel DP, so that the efficiency of the light provided from the light emitting unit LU to the liquid crystal display panel DP can be increased. In addition, the filter layer FL can block a portion of the light scattered in the color conversion layer CCL and provided to the lower side of the optical member OM. Therefore, a portion of the light scattered in the color conversion layer CCL of the optical member OM and diffused in the direction of the light source member LM is blocked by the filter layer FL, so that the display quality of the display device DD can be improved. The filter layer FL may be a single layer or a stacked layer of a plurality of insulating films. For example, the filter layer FL is formed to include a plurality of insulating films, and the transmission wavelength range and the reflection wavelength range may be determined according to the number of stacked layers, the thickness of each stacked layer, and the refractive index difference between the stacked layers.

[0109] Reference Fig. 7A In an exemplary embodiment, the filter layer FL may include a first insulating layer L10 and a second insulating layer L20 having different refractive indices. The first insulating layer L10 and the second insulating layer L20 may also be referred to as a first insulating film L10 and a second insulating film L20, respectively. The filter layer FL may include at least one first insulating film L10 and at least one second insulating film L20. The refractive index of the first insulating film L10 may be 1.4 to 1.6, and the refractive index of the second insulating film L20 may be 1.9 to 2.1.

[0110] For example, a metal oxide material may be used for the second insulating layer L20 having a relatively high refractive index. Specifically, the second insulating layer L20 having a high refractive index may include TiO x 、TaO x , HfO x and ZrO x In addition, the first insulating layer L10 having a relatively low refractive index may include SiO x 、SiCO x In addition, in the embodiment, SiN x and SiO x To form the filter layer FL.

[0111] The first insulating film L10 and the second insulating film L20 stacked continuously may be defined as a unit layer L-P2. The filter layer FL may include a plurality of unit layers L-P2. For example, the filter layer FL may include 5 or more and 15 or less unit layers L-P2. However, the inventive concept is not limited thereto, and the configuration of the filter layer FL may vary depending on the color quality achieved in the display device DD.

[0112] In addition, the thicknesses of the first insulating films L10 included in the unit layer L-P2 may be different from each other, and the thicknesses of the second insulating films L20 included in the unit layer L-P2 may be different from each other. Figure 7B is a graph showing optical characteristics of the filter layer FL according to an exemplary embodiment. Figure 7B The graph shown in shows the reflectivity of each wavelength according to the incident angle of light incident on the filter layer FL. Figure 7B The sample used in the evaluation shown in is manufactured to have a stacked structure of base substrate BS / filter layer FL / color conversion layer CCL. The light emitting unit LU used emits blue light, and the color conversion layer CCL includes quantum dots QD1 and QD2 that are excited by blue light and emit red and green light. On the other hand, the filter layer FL uses SiO x As the first insulating film L10, SiN x As the second insulating film L20, 13 unit layers L-P2 are used.

[0113] Reference Figure 7B , it can be seen that the central wavelength range of the light reflected by the filter layer FL changes according to the incident angle of the light incident on the filter layer FL. Figure 7B It can be seen that as the incident angle of the light incident on the filter layer FL increases, the central wavelength of the light reflected by the filter layer FL changes to a short wavelength. Figure 7B , it can be seen that when the incident angle of the light incident on the filter layer FL is 10°, most of the light is reflected in the region of 500nm to 700nm. In contrast, it can be seen that as the incident angle gradually increases to 40° and 60°, the wavelength of the light reflected from the filter layer FL moves to the short wavelength range, so that the central wavelength of the reflected light moves to less than 500nm. In addition, it can be seen that as the incident angle gradually increases to 40° and 60°, the reflectivity of the light reflected from the filter layer FL decreases compared to the case where the incident angle is 10°.

[0114] Reference Figure 7B , when the incident angle of the light incident on the filter layer FL is a low angle, the filter layer FL reflects most of the light in the region of 500nm to 700nm to transmit the blue light and effectively reflect the red light and the green light. However, it can be seen that as the incident angle of the light incident on the filter layer FL becomes larger, the wavelength range of the reflected light moves to the short wavelength range, so that the light of the portion of the wavelength range corresponding to the red light and the green light among the light cannot be effectively reflected, and the reflectivity also decreases.

[0115] That is, the optical member OM includes the filter layer FL to reflect red and green light, of the light, which is scattered by the color conversion layer CCL and guided toward the lower portion of the optical member OM, thereby increasing light efficiency and improving color quality. However, as the incident angle of light incident on the filter layer FL increases and becomes a high angle, the function of reflecting the entire green and red light regions may be deteriorated.

[0116] Therefore, refer to Figure 5 The optical member OM of the exemplary embodiment may include a filter layer FL disposed on the upper surface (eg Figure 5 The optical path changing layer may change the path of light provided to the filter layer FL, or change the path of light emitted from the filter layer FL. The optical path changing layer may be a low refractive layer LRL or a pattern layer OPL (see Fig.14 For example, the light path changing layer may optimize the selective transflective function of the filter layer FL by reducing the incident angle of light provided to the filter layer FL to a low angle.

[0117] In an exemplary embodiment, the light path changing layer may be a low refractive layer LRL having a refractive index lower than that of the color conversion layer CCL. Since the low refractive layer LRL has a refractive index lower than that of the color conversion layer CCL, the path of the light provided to the low refractive layer LRL can be changed by refracting or reflecting the light provided from the color conversion layer CCL to the low refractive layer LRL.

[0118] The refractive index of the low refractive layer LRL may be less than 1.4. For example, the refractive index of the low refractive layer LRL may be between 0.1 or more and 1.4 or less. The low refractive layer LRL may be directly disposed on the upper surface or the lower surface of the filter layer FL.

[0119] The low refractive layer LRL may be a layer including at least one low refractive index material, or may be formed of a material having low refractive properties itself. When the low refractive layer LRL includes at least one low refractive index material, the low refractive index material may be voids, hollow inorganic particles, porous silica particles, or a siloxane polymer having a cage structure.

[0120] Figure 8 is a cross-sectional view showing a low refractive layer LRL according to an exemplary embodiment. Figure 8 , the low-refractive layer LRL may include a matrix part MX, hollow inorganic particles HP, and voids VD. The low-refractive layer LRL may include a plurality of hollow inorganic particles HP and a plurality of voids VD. The plurality of hollow inorganic particles HP may be dispersed and disposed in the matrix part MX, and the plurality of voids VD may be defined by the matrix part MX. The voids VD correspond to a portion that is not filled with the matrix part MX.

[0121] and Figure 8 Different from that shown in , the low-refractive layer LRL according to the exemplary embodiment may include at least one of the hollow inorganic particles HP and the voids VD. For example, the low-refractive layer LRL may include the hollow inorganic particles HP and the matrix part MX, or the low-refractive layer LRL may include the matrix part MX and the voids VD defined by the matrix part MX.

[0122] The low refractive layer LRL according to an exemplary embodiment may include a siloxane polymer, and the siloxane polymer may include a fluorinated siloxane unit or may have a cage compound structure such as silsesquioxane.

[0123] The matrix part MX may include a polymer material. The matrix part MX may include at least one of an acrylic polymer, a siloxane polymer, a polyurethane polymer, and an imide polymer. For example, the matrix part MX may include any polymer material selected from an acrylic polymer, a siloxane polymer, a polyurethane polymer, and an imide polymer, or a combination of multiple selected polymer materials.

[0124] The matrix part MX may be formed of acrylic resin, silicone resin, polyurethane resin, or imide resin. The matrix part MX may be formed by providing a polymer resin and then curing the polymer resin in a high temperature process or an ultraviolet treatment process.

[0125] The hollow inorganic particles HP may be in the form of a core-shell. In an embodiment, the hollow inorganic particles HP may be spherical. Each hollow inorganic particle HP may include a core portion and a shell portion surrounding the core portion. The core portion may be defined by the shell portion. The shell portion may be a layer formed of an inorganic material. The shell portion may include SiO 2 MgF 2 and Fe 3 O 4 For example, the hollow inorganic particles HP of the low refractive layer LRL may be hollow silica.

[0126] The core part may be filled with air. On the other hand, the inventive concept is not limited thereto, and in the hollow inorganic particle HP, the core part may be filled with a liquid or a gas having a low refractive property.

[0127] The void VD included in the low-refractive layer LRL of the exemplary embodiment may be a portion defined by the matrix portion MX. The void VD may not be filled with the matrix portion MX, and the void VD may have an empty interior. For example, the void VD may be an empty space defined by the matrix portion MX. On the other hand, the void VD may be a portion filled with air, and the air-filled void VD may be a portion that reduces the refractive index value of the low-refractive layer LRL.

[0128] Although according to Figure 8 The voids VD in the low refractive layer LRL of the exemplary embodiment shown in FIG. 1 are shown to have any shape, but the inventive concept is not limited thereto. In another exemplary embodiment, the voids VD may be spaces having a spherical form.

[0129] In the low refractive layer LRL of the exemplary embodiment, the void VD may be formed by a pore inducing material (e.g., a porogen). The pore inducing material may be a linear or branched organic material. The pore inducing material may be provided together with the polymer resin forming the matrix part MX and then removed to form the void VD.

[0130] The linear pore inducing material may be made of (x, y and n are each an independent integer of 1 or greater), or may be a single hydrocarbon molecule represented by branched poly(p-xylene), linear poly(p-phenylene), linear polybutadiene, branched polyethylene, polycarbonate, polyamideimide, polyphthalamide or polymethylstyrene.

[0131] In addition, the dendrite-type pore inducing material may include a core part and a branch part bonded to the core part and connected in a regular branch structure to have a form of diffusion to the outside. In the dendrite-type pore inducing material, cyclosiloxane, cyclodextrin, benzene, etc. may be applied to the core part. In addition, The represented hydrocarbon groups can be applied to the branched portions in the dendritic pore-inducing material.

[0132] In an exemplary embodiment, the low-refractive layer LRL may be a metal layer. The low-refractive layer LRL may be a single-layer metal layer. The low-refractive layer LRL may be a layer formed of a metal material such as Ag, Al, Cu, or Au. Alternatively, the low-refractive layer LRL may be a layer formed of an alloy of a metal material such as Ag, Al, Cu, or Au. For example, the low-refractive layer LRL may be a layer made of only a metal material such as Ag, Al, Cu, or Au, or a layer formed of an alloy of Cu-Zn.

[0133] The low refractive layer LRL may be or greater When the thickness of the metal layer is less than When the thickness of the metal layer is greater than 1000 mm, the metal materials constituting the metal layer may aggregate with each other, thereby failing to provide the low refractive layer LRL having a uniform thickness. In the case where the transmittance of the metal layer is less than 90% and is included in the optical member OM, the light efficiency of the display device DD may be reduced.

[0134] Fig. 9 is a view exemplarily showing an optical path in a conventional display device DD', Fig.10 Schematic diagram showing a light path in a display device DD of an exemplary embodiment. Fig. 9 and Fig.10In the embodiment, the first display area ON-A corresponds to the area of ​​the liquid crystal display panel DP corresponding to the turned-on light emitting element LD1 in the light emitting unit LU, and the second display area OFF-A1 and the third display area OFF-A2 correspond to the areas of the liquid crystal display panel DP corresponding to the turned-off light emitting element LD2 in the light emitting unit LU. The first display area ON-A corresponding to the turned-on light emitting element LD1 displays a color image, and the second display area OFF-A1 and the third display area OFF-A2 corresponding to the turned-off light emitting element LD2 can display a black image.

[0135] Unlike the display device DD of the inventive concept, Fig. 9 The conventional display device DD' shown in FIG. 1 does not include a filter layer and a light path changing layer in the optical member OM'.

[0136] In the operation of the conventional display device DD', light L emitted from the turned-on light emitting element LD1 among the light emitting elements included in the light emitting unit LU 0 Passing through the color conversion layer CCL and acting as the first light L 1 ' is provided to the liquid crystal display panel DP. The first light L 1 ' includes light L emitted from the light emitting element LD1 0 When the light L provided from the light emitting element LD1 0 The first light L is obtained when it is converted in the color conversion layer CCL and provided. 1 ' may include all lights in blue light, green light and red light. That is, the first light L 1 'It can be white light which includes all of blue light, green light and red light.

[0137] On the other hand, the light L scattered in the color conversion layer CCL S ' may be incident on the second display area OFF-A1 or the third display area OFF-A2 provided with the turned-off light emitting element LD2. In addition, the light L incident on the second display area OFF-A1 or the third display area OFF-A2 S A portion of ' can be reflected and used as reflected light L R 'It is incident on the color conversion layer CCL again.

[0138] With the first light L 1 'Similarly, as scattered light, light L S ' can include all the light in blue, green and red. S 'Similar, light L R '(ie, reflected light) may also include all of blue light, green light and red light.

[0139] The reflected light L incident on the color conversion layer CCL R', the blue light can again excite the quantum dots contained in the color conversion layer CCL. Therefore, in addition to the reflected light L R In addition to the blue, green and red light in the 2 'Including is included in the reflected light L R The blue light in the 'is excited and converted into green and red light, the second light L 2 ' is light transmitted through the color conversion layer CCL again and provided to the second display area OFF-A1 or the third display area OFF-A2. Therefore, due to the second light L emitted from the display areas OFF-A1 and OFF-A2 corresponding to the turned-off light emitting element LD2 2 'Reflected light L R 'excitation, and also includes light provided from the color conversion layer CCL, so the ratio of red light and green light becomes higher than that of red light and green light in conventional white light, so that the light can be emitted as yellowish light.

[0140] That is, the display areas OFF-A1 and OFF-A2 corresponding to the turned-off light emitting element LD2 should display a black image, but if there is a turned-on light emitting element LD1 and a turned-off light emitting element LD2 adjacent thereto, yellowish light is emitted in the display areas OFF-A1 and OFF-A2 corresponding to the turned-off light emitting element LD2. Therefore, the yellow ring phenomenon occurs near the boundary line BRL between the first display area ON-A corresponding to the turned-on light emitting element LD1 and the display areas OFF-A1 and OFF-A2 corresponding to the turned-off light emitting element LD2.

[0141] Fig.10 Schematically shows the Figure 5 2 is a diagram showing an optical path in the case of a configuration of a display device DD of an exemplary embodiment.

[0142] The light L emitted from the turned-on light emitting element LD1 among the light emitting elements included in the light emitting unit LU 0 Passing through the color conversion layer CCL and acting as the first light L 1 is provided to the liquid crystal display panel DP. The first light L 1 The light L emitted from the light emitting element LD1 0 When the light L provided from the light emitting element LD1 0 The first light L is obtained when it is converted in the color conversion layer CCL and provided. 1 The first light L may include all of the blue light, green light, and red light. 1 White light including all of blue light, green light, and red light may be provided to the liquid crystal display panel DP.

[0143] On the other hand, light L SIt can be incident on the low refractive layer LRL, light L S It is a part of the light scattered in the color conversion layer CCL. S The incident angle θ1 can be less than the critical angle, and the light L S is the scattered light incident on the low refractive layer LRL. That is, the light L incident on the low refractive layer LRL at an angle smaller than the critical angle S The light is refracted and incident on the filter layer FL, and the filter layer FL can transmit some of the light and reflect some of the light. Fig.10 , the incident angle of light incident on the low refractive layer LRL may represent an angle increased based on an imaginary line RL extending in a normal direction with respect to an upper surface of the low refractive layer LRL.

[0144] The light L transmitted through the filter layer FL FL-T A portion of the light L incident on the second display area OFF-A1 may be incident on the second display area OFF-A1 provided with the turned-off light emitting element LD2. FL-T On the other hand, the light L transmitted through the filter layer FL FL-T A portion of the light can be reflected by the light emitting unit LU and can be used as the reflected light L R It is incident on the color conversion layer CCL again.

[0145] The reflected light L incident on the color conversion layer CCL R In the second light L, the blue light can again excite the quantum dots contained in the color conversion layer CCL. 2 The second light L may include blue light, green light and red light, and may be white light whose color balance matches. 2 is the light transmitted through the color conversion layer CCL again and provided to the second display area OFF-A1 of the liquid crystal display panel DP. Fig. 9 Description of the second light L 2 'Different, in Fig.10 Medium, light L 2 Is not changed to yellowish white light, light L 2 It is the second light emitted to the second display area OFF-A1, and with the display device DD of this exemplary embodiment, the yellow ring which is a problem in the conventional display device DD' can be improved to show excellent display details.

[0146] On the other hand, the scattered light L is scattered in the color conversion layer CCL and incident on the low refractive layer LRL. S A portion of the light L may be reflected in the filter layer FL. FL-R Can be red light or green light. Reflected light L FL-RThe light may be incident on the color conversion layer CCL again.

[0147] exist Fig.10 In the light L scattered in the color conversion layer CCL S-a 2 shows a case where the angle θ2 incident on the low refractive layer LRL is larger than the critical angle. The scattered light L having an incident angle larger than the critical angle S-a can be totally reflected in the low refractive layer LRL, for example, totally reflected as light L LR-a That is, the scattered light L S-a The light may be totally reflected on the upper surface of the low refraction layer LRL and then be incident on the color conversion layer CCL.

[0148] Therefore, the display device DD of this exemplary embodiment includes both the low refractive layer LRL and the filter layer FL in the optical member OM to reflect and block or selectively transmit and reflect the light scattered in the color conversion layer CCL and guided to the light source member, so that the degradation of the color quality in the display areas OFF-A1 and OFF-A2 corresponding to the turned-off light emitting element LD2 can be prevented. Therefore, the display device DD of this exemplary embodiment includes the color conversion layer CCL having quantum dots, the filter layer FL disposed on the lower side of the color conversion layer CCL, and the low refractive layer LRL disposed on at least one of the upper surface and the lower surface of the filter layer FL, thereby showing excellent color reproducibility and improved display quality.

[0149] In addition, although not shown in the drawings, when the low refractive layer LRL is located on the upper surface of the filter layer FL, the low refractive layer LRL is dispersed in the color conversion layer CCL and can filter the light L incident on the filter layer FL. LR Therefore, the filter layer FL can effectively transmit or reflect the incident light, so that the color quality of the display device DD can be improved.

[0150] Although the reference Fig.10 The optical path of the exemplary embodiment in which the low refractive layer LRL is disposed on the upper surface of the filter layer FL is described, but unlike this, even when the low refractive layer LRL is disposed on the lower surface of the filter layer FL, the display quality of the display device DD of the exemplary embodiment can be improved. For example, if the low refractive layer LRL is disposed on the lower surface of the filter layer FL, the traveling direction of the light that passes through the filter layer FL and is guided toward the light emitting unit LU can be reduced to a low angle, so that the amount of light guided to the display areas OFF-A1 and OFF-A2 corresponding to the turned-off light emitting element LD2 can be reduced.

[0151] Fig.11A and Fig. 11B 2 is a cross-sectional view showing optical members OM-1 and OM-1a according to an exemplary embodiment. Fig.11A and Fig. 11B According to the embodiment, the optical members OM-1 and OM-1a may further include a scattering layer SL. The scattering layer SL may be disposed on the upper side or the lower side of the color conversion layer CCL. Fig.11A and Fig. 11B In the optical members OM-1 and OM-1a of the embodiments shown in FIG. 1 , regarding the base substrate BS, the filter layer FL, the low refractive layer LRL, the color conversion layer CCL, and the barrier layers BL1 and BL2, the same as those described in reference 1 can be applied. Figures 1 to 10 The scattering layer SL can scatter the light from the light emitting unit LU (see Figure 5 ) and passes through the base substrate BS to prevent the hot spot phenomenon. On the other hand, the scattering layer SL may include a base resin and scattering particles mixed (or dispersed) in the base resin. The scattering particles may include inorganic particles. The scattering layer SL may include TiO 2 、SiO 2 、ZnO、Al 2 O 3 ,BaSO 4 、CaCO 3 and ZrO 2 At least one of the scattering particles.

[0152] In accordance with Fig.11A In the optical member OM-1 of the exemplary embodiment shown in FIG. 1 , the scattering layer SL may be disposed on the lower side of the color conversion layer CCL. The scattering layer SL may be disposed between the base substrate BS and the filter layer FL. The scattering layer SL may be disposed directly on the upper surface of the base substrate BS.

[0153] In accordance with Fig. 11B In the optical member OM-1a of the exemplary embodiment shown in FIG. 1 , the scattering layer SL may be disposed on the upper side of the color conversion layer CCL. For example, the scattering layer SL may be the uppermost layer of the optical member OM-1a. Fig. 11B In the case of the optical member OM-1a of the embodiment shown in FIG, since the scattering layer SL is the uppermost layer and can be used as a protective layer for protecting the color conversion layer CCL, the blocking layer BL2 provided on the upper surface of the color conversion layer CCL can be omitted unlike shown in the drawings. Fig. 12A is a cross-sectional view showing an optical member OM-2 according to an exemplary embodiment. Fig.11A or Fig. 11B Compared with the optical member OM-1 or OM-1a shown in FIG. Fig. 12A The optical member OM-2 shown in FIG. 1 has a structure in which the scattering layer SL is omitted, and the configuration of the color conversion layer CCL-a is the same as that of Fig.11A or Fig. 11BThe configuration of the color conversion layer CCL shown in FIG. 1 is partially different. Fig. 12A In the optical member OM-2 of this exemplary embodiment shown in FIG. 1 , regarding the base substrate BS, the filter layer FL, the low refractive layer LRL, and the barrier layers BL1 and BL2, the same as described in reference 1 can be applied. Figures 1 to 10 The content described is the same as the content.

[0154] Fig. 12B It shows that the Fig. 12A 2 is a cross-sectional view of a color conversion layer CCL-a in an optical member OM-2. In addition to the matrix resin BR and at least one quantum dot QD1 or QD2 dispersedly disposed in the matrix resin BR, the color conversion layer CCL-a according to an exemplary embodiment may further include scattering particles SP. The scattering particles SP may be TiO 2 Or silica-based nanoparticles. The scattering particles SP may scatter light emitted from the quantum dots QD1 and QD2 to be emitted to the outside of the color conversion layer CCL-a.

[0155] In other words, Fig. 12B As shown in FIG. , if the color conversion layer CCL-a includes scattering particles SP, then Fig.11A and Fig. 11B Compared with the optical members OM-1 and OM-1a shown in FIG. 1 , even when the scattering layer SL is omitted, according to Fig. 12A The optical member OM-2 of the exemplary embodiment may also exhibit improved light uniformity.

[0156] Fig.13A and Fig. 13B 2 are cross-sectional views respectively illustrating optical members OM-3 and OM-3a according to exemplary embodiments. Fig.14 The exemplary embodiment includes Fig.13A 2 is an optical path in the display device DD-1 of the exemplary embodiment of the optical member OM-3 of the exemplary embodiment shown in FIG.

[0157] The optical members OM-3 and OM-3a according to the exemplary embodiments may include a pattern layer OPL as an optical path changing layer. The pattern layer OPL may include a plurality of protrusions OP. The protrusions OP may be formed protruding from the base substrate BS toward the color conversion layer CCL. The protrusions OP of the pattern layer OPL may be formed by mechanical etching, chemical etching, etc. Fig.13A and Fig. 13B In the optical members OM-3 and OM-3a of the exemplary embodiments shown in FIG. 1 , regarding the base substrate BS, the filter layer FL, the color conversion layer CCL, and the blocking layers BL1 and BL2, the same as described in reference 1 can be applied. Figures 1 to 10 The content described is the same as the content.

[0158] In accordance with Fig.13A and Fig. 13B In the optical members OM-3 and OM-3a of the exemplary embodiments shown in FIG. 1 , the protrusion OP has a lens shape, but the inventive concept is not limited thereto. The protrusion OP may be provided in various shapes. The protrusion OP may be used to refract light incident from the color conversion layer CCL on the pattern layer OPL to change the light path.

[0159] Reference Fig.13A , the pattern layer OPL may be disposed between the filter layer FL and the color conversion layer CCL. The pattern layer OPL changes the optical path by refracting the light emitted from the color conversion layer CCL and directed toward the lower portion of the color conversion layer CCL, so that the incident angle of the light incident on the filter layer FL may be reduced. The pattern layer OPL may allow the light incident on the filter layer FL to have a low angle. Therefore, the filter layer FL may effectively transmit or reflect the incident light, so that the color quality of the display device DD-1 may be improved.

[0160] On the other hand, Fig.13A The exemplary embodiments shown in FIG. Fig. 13B 1 shows a difference: the pattern layer OPL is disposed on the lower surface of the filter layer FL. If the pattern layer OPL is disposed on the lower surface of the filter layer FL, the traveling direction of the light passing through the filter layer FL and guided toward the light emitting unit LU can be reduced to a low angle, so that the amount of light guided to the display areas OFF-A1 and OFF-A2 corresponding to the turned-off light emitting element LD2 can be reduced. Therefore, when using Fig. 13B In the case of another optical member OM-3a in the exemplary embodiment shown in FIG. 1 , the display quality of the display device DD-1 can be improved.

[0161] Fig.14 The optical paths in the display device DD-1 of the exemplary embodiment are schematically shown.

[0162] The light L emitted from the light emitting element LD1 turned on among the light emitting elements included in the light emitting unit LU 0 Passing through the color conversion layer CCL and acting as the first light L 1 is provided to the liquid crystal display panel DP. The first light L 1 The light L emitted from the light emitting element LD1 0 When the light L provided from the light emitting element LD1 0 The first light L is obtained when it is converted in the color conversion layer CCL and provided. 1 The first light L may include all of the blue light, green light, and red light. 1 White light including all of blue light, green light, and red light may be provided to the liquid crystal display panel DP.

[0163] On the other hand, light L which is a part of the light scattered in the color conversion layer CCL S1 The light L as scattered light incident on the pattern layer OPL may be incident on the pattern layer OPL. S1 The light L passing through the pattern layer OPL may be refracted at the protrusion OP of the pattern layer OPL and may be reduced to have a low angle and be incident on the filter layer FL. OPL1 The light L having a low angle and incident on the filter layer FL and transmitted through the filter layer FL FL-T1 The light is not incident on the region of the light emitting element LD2 which is turned off, but can be reflected again in the region corresponding to the light emitting element LD1 which is turned on and is transmitted as the reflected light L R1 The pattern layer OPL makes the light scattered in the color conversion layer CCL have a low angle and minimizes the amount of light that may be incident on the display area OFF-A1 corresponding to the turned-off light emitting element LD2, so that the display quality can be improved. In addition, on the other hand, the light L which is part of the light scattered in the color conversion layer CCL S2 The light L incident on the pattern layer OPL and as scattered light incident on the pattern layer OPL S2 The light L transmitted through the pattern layer OPL and incident on the filter layer FL may be refracted in the protrusion OP of the pattern layer OPL and incident on the filter layer FL. OPL2 The light L is transmitted through the filter layer FL. FL-T2 The light L incident on the third display area OFF-A2 may be incident on the third display area OFF-A2 in which the turned-off light emitting element LD2 is disposed. FL-T2 On the other hand, the light L transmitted through the filter layer FL FL-T2 A portion of the light can be reflected by the light emitting unit LU and can be used as the reflected light L R2 It is incident on the color conversion layer CCL again.

[0164] The reflected light L incident on the color conversion layer CCL R2 In the embodiment, the blue light can again excite the quantum dots contained in the color conversion layer CCL. Therefore, the second light L as the light that is again transmitted through the color conversion layer CCL and provided to the third display area OFF-A2 2 It can include blue, green, and red light, and can be white light whose color balance matches that of the light used as a reference. Fig. 9 Description of the second light L 2 'Different, in Fig.14 , the light L as the second light emitted to the third display area OFF-A2 2is white light that is not changed to yellowish, and in the case of the display device DD-1 of this exemplary embodiment, it is possible to improve the conventional display device DD' (see Fig. 9 ) in the problem to show excellent display fineness.

[0165] The display device of the exemplary embodiment can display excellent color quality by disposing an optical member including a color conversion layer having quantum dots between the light source member and the liquid crystal display panel. In addition, the optical member can display improved display quality by including both a filter layer and an optical path changing layer on the lower side of the color conversion layer.

[0166] The exemplary embodiment includes a filter layer disposed on the lower side of the color conversion layer and transmitting / reflecting light in a selective wavelength range, and a light path changing layer disposed on the upper surface or the lower surface of the filter layer to change the path of light incident on or emitted from the filter layer. Therefore, the display quality of a display device having a direct type light source can be improved.

[0167] Exemplary embodiments provide an optical member including a color conversion layer having quantum dots, a filter layer selectively transmitting / reflecting incident light, and an optical path changing layer, so that a display device with improved display quality can be provided.

[0168] Exemplary embodiments provide an optical member including a light path changing layer and a filter layer disposed on an upper side of a light source member and selectively transmitting / reflecting incident light, so that a display device having improved display quality can be provided.

[0169] Although some exemplary embodiments have been described herein, other embodiments and modifications will be apparent from this description. Therefore, the inventive concept is not limited to these embodiments, but is limited to the broader scope of the appended claims and various obvious modifications and equivalent arrangements that will be apparent to those of ordinary skill in the art.

Claims

1. A display device, comprising: A light source member including a plurality of light emitting units emitting light of a first color; an optical member disposed on an upper side of the light source member; as well as a liquid crystal display panel disposed on an upper side of the optical member, The optical component includes: a base substrate; a color conversion layer, which is disposed on the base substrate and includes quantum dots for converting the first color light into second color light and third color light; a filter layer, which is disposed between the base substrate and the color conversion layer and transmits the first color light and reflects the second color light and the third color light; and an optical path changing layer, which is directly disposed on at least one of the upper surface and the lower surface of the filter layer and is disposed between the color conversion layer and the light source component to reduce the incident angle of light provided to the filter layer. wherein the optical path changing layer is a low refractive layer having a refractive index smaller than that of the color conversion layer, or a pattern layer including a plurality of protrusions, and The filter layer includes a plurality of first insulating films and a plurality of second insulating films alternately arranged with the first insulating films, and the refractive index of the first insulating films and the refractive index of the second insulating films are different from each other.

2. The display device according to claim 1, wherein: The plurality of light emitting units include: Circuit boards; and A plurality of light emitting elements are disposed on the circuit board and are configured to be turned on and off independently of each other.

3. The display device according to claim 1, wherein: The optical path changing layer is directly disposed on the upper surface or the lower surface of the filter layer.

4. The display device according to claim 1, wherein: The low-refractive layer comprises a low-refractive index material; and The low refractive index material includes at least one of voids, hollow inorganic particles, porous silica particles, and siloxane polymers.

5. The display device according to claim 1, wherein: The low refractive layer is a metal layer formed of a metal material of Ag, Al, Cu or Au or an alloy of the metal material; and The thickness of the metal layer is greater than or equal to 30 and less than or equal to 100 .

6. The display device according to claim 5, wherein: The metal layer is a single layer.

7. The display device according to claim 1, wherein: The plurality of protrusions protrude from the base substrate toward the color conversion layer.

8. The display device according to claim 1, wherein: The refractive index of the first insulating film is greater than or equal to 1.4 and less than or equal to 1.6; and The refractive index of the second insulating film is greater than or equal to 1.9 and less than or equal to 2.

1.

9. The display device according to claim 1, wherein: The optical member further includes a barrier layer disposed on at least one of an upper surface and a lower surface of the color conversion layer.

10. The display device according to claim 1, wherein: The optical member further includes a scattering layer disposed on an upper side or a lower side of the color conversion layer.

11. The display device according to claim 10, wherein: The scattering layer includes scattering particles of at least one of TiO2, SiO2, ZnO, Al2O3, BaSO4, CaCO3 and ZrO2.

12. The display device according to claim 1, wherein: The central wavelength of the first color light is in the range of 420 nm to 470 nm, inclusive; The central wavelength of the second color light is in the range of 520 nm to 570 nm inclusive; and The central wavelength of the third color light is in the range of 620 nm to 670 nm inclusive.

13. A display device, comprising: A light source component, comprising a plurality of light-emitting units; an optical member disposed on an upper side of the light source member; as well as a liquid crystal display panel disposed on an upper side of the optical member, wherein the optical member comprises: a base substrate; a color conversion layer disposed on the base substrate and comprising quantum dots; a filter layer disposed between the base substrate and the color conversion layer and configured to transmit light having a central wavelength in a range of 420 nm to 470 nm including 420 nm and 470 nm among incident light, and reflect light having a central wavelength in a range of 520 nm to 670 nm including 520 nm and 670 nm; and an optical path changing layer disposed directly on at least one of an upper surface and a lower surface of the filter layer and disposed between the color conversion layer and the light source member to reduce an incident angle of light provided to the filter layer, wherein the optical path changing layer is a low refractive layer having a refractive index smaller than that of the color conversion layer, or a pattern layer including a plurality of protrusions, and The filter layer includes a plurality of first insulating films and a plurality of second insulating films alternately arranged with the first insulating films, and the refractive index of the first insulating films and the refractive index of the second insulating films are different from each other.

14. The display device according to claim 13, wherein: The filter layer reflects 80% or more of light having a central wavelength within a range of 520 nm to 670 nm inclusive, among light incident in a normal direction of the upper surface or the lower surface.

15. The display device according to claim 13, wherein: The low-refractive layer has a refractive index greater than or equal to 0.1 and less than or equal to 1.

4.

16. A display device, comprising: Optical components; a light source member disposed on a lower side of the optical member and including a plurality of light emitting units for providing blue light to the optical member; as well as a liquid crystal display panel disposed on an upper side of the optical member, The optical member includes: a base substrate; a color conversion layer, which is disposed on the base substrate and includes a first quantum dot excited by the blue light to emit green light and a second quantum dot excited by the blue light to emit red light; a filter layer, which is disposed between the base substrate and the color conversion layer to transmit the blue light and reflect the green light and the red light; and an optical path changing layer, which is directly disposed on at least one of an upper surface and a lower surface of the filter layer and is disposed between the color conversion layer and the light source member to reduce an incident angle of light provided to the filter layer. wherein the optical path changing layer is a low refractive layer having a refractive index smaller than that of the color conversion layer, or a pattern layer including a plurality of protrusions, and The filter layer includes a plurality of first insulating films and a plurality of second insulating films alternately arranged with the first insulating films, and the refractive index of the first insulating films and the refractive index of the second insulating films are different from each other.

17. The display device according to claim 16, wherein: The plurality of protrusions protrude from the base substrate toward the color conversion layer.

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