Patent Publication Number: US-2020292884-A1

Title: Backlight assembly and liquid crystal display device including the same

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. § 119 from, and the benefit of, Korean Patent Application No. 10-2019-0029542, filed on Mar. 14, 2019 in the Korean Intellectual Property Office, the contents of which are herein incorporated by reference in their entirety. 
     BACKGROUND 
     1. Technical Field 
     Embodiments of the present disclosure are directed to a backlight assembly and a liquid crystal display device that includes the same. 
     2. Discussion of the Related Art 
     A liquid crystal display device receives light from a backlight assembly and displays an image. Some backlight assemblies include a light source and a light guide plate. The light guide plate receives light from the light source and guides the light toward a display panel. In some products, light received from the light source is white light, and the white light is filtered using a color filter disposed in the display panel to impart a color. 
     Recently, wavelength conversion films have been developed to improve image quality, such as color reproducibility, etc., of a liquid crystal display device. A blue light source is usually used as the light source, and the wavelength conversion film is disposed on the light guide plate to convert light into white light. The wavelength conversion film can be combined together with an optical film which improves luminance by controlling the optical characteristics of light propagating through the wavelength conversion film. 
     A liquid crystal display device also includes fixing members such as a lower accommodation container, a light guide plate fixing portion, and a mold frame, which couple the light guide plate, the optical film, the display panel, etc. However, when the light guide plate, the optical film, and the display panel are coupled using different fixing members, an assembling process, an assembling time, and a manufacturing cost increases. In addition, this process is not used to manufacture a slim display device that has a three-surface frameless structure or a moldless structure, etc. 
     SUMMARY 
     Embodiments of the present disclosure provide a display device that can prevent movement of a backlight assembly by integrating a plurality of fixing members into one unit. 
     Embodiments of the present disclosure also provide a display device that can prevent light leakage through a bendable portion of a fixing member. 
     According to an embodiment of the present disclosure, a backlight assembly includes an optical member, a bottom chassis that includes a bottom surface on which the optical member is disposed, a first sidewall portion that protrudes in a first direction from a first side of the bottom surface, and a first support portion that protrudes from the first sidewall portion in a second direction that intersects the first direction, and an assembly member that includes a body, and, protruding from the body, a first protrusion and a second protrusion. The second protrusion overlaps an outer surface of the first support portion. 
     In an exemplary embodiment, the body includes a first upper surface portion and a first side surface portion that extends downward from the first upper surface portion. The first upper surface portion includes a corner portion that forms a right angle in a plan view, a peripheral portion that is spaced apart from the corner portion, and has a first side and a second side that connect the corner portion and the peripheral portion. 
     In an exemplary embodiment, the first protrusion extends from a portion of the first side and a portion of the second side and includes a second upper surface portion and a second side surface portion that extends downward from the second upper surface portion. 
     In an exemplary embodiment, the first upper surface portion is coplanar with the second upper surface portion, and the first side surface portion is coplanar with the second side surface portion. 
     In an exemplary embodiment, the optical member includes a plurality of corner portions, and each corner portion of the optical member is in contact with the first side surface portion and the second side surface portion. 
     In an exemplary embodiment, the assembly member further includes a third protrusion that extends from the second side surface portion of the first protrusion. 
     In an exemplary embodiment, a lower surface of the third protrusion is in contact with an upper surface of the optical member. 
     In an exemplary embodiment, the first sidewall portion of the bottom chassis further includes a latch stepped portion and the second side surface portion of the first protrusion includes a coupling hole that couples to the latch stepped portion. 
     In an exemplary embodiment, the assembly member includes a second sidewall portion that extends upward from the peripheral portion. 
     In an exemplary embodiment, the second protrusion extends from the second sidewall portion parallel to the second sidewall portion of the first protrusion. 
     In an exemplary embodiment, the body includes a first lower surface portion opposite to the first upper surface portion, and the backlight assembly further includes a first adhesive member disposed between the first lower surface portion and the first support portion. 
     In an exemplary embodiment, the backlight assembly further includes a spacer tape disposed on the first support portion. Both ends of the spacer tape are disposed along boundaries between the body, and the first protrusion and the second protrusion. 
     In an exemplary embodiment, the optical member includes a light guide plate, a wavelength conversion layer disposed on the light guide plate, and a passivation layer that covers the wavelength conversion layer. 
     In an exemplary embodiment, the backlight assembly further includes an optical films disposed on the optical member. 
     In an exemplary embodiment, the optical film includes at least one of a diffusion layer, a prismatic pattern layer, or a reflective polarizing layer. 
     According to an embodiment of the present disclosure, a display device includes a display panel, and a backlight assembly disposed on one surface of the display panel and that provides light to the display panel. The backlight assembly includes an optical member and an assembly member that includes a body that includes a first upper surface portion, a first side surface portion that extends downward from the first upper surface portion, and a first protrusion and a second protrusion that protrude from the body. The first protrusion includes a second upper surface portion and a second side surface portion that extends downward from the second upper surface portion, and the optical member comprises a plurality of corner portions, and the corner portions of the optical member are disposed in contact with the first side surface portion and the second side surface portion. 
     In an exemplary embodiment, the first protrusion extends from a portion of the first side and a portion of the second side, and the first upper surface portion includes a corner portion that forms a right angle in a plan view, a peripheral portion spaced apart from the corner portion, and a first side and a second side that connect the corner portion and the peripheral portion. 
     In an exemplary embodiment, the first upper surface portion is coplanar with the second upper surface portion, and the first side surface portion is coplanar with the second side surface portion. 
     In an exemplary embodiment, the backlight assembly further comprises a bottom chassis that includes a bottom surface on which the optical member is disposed, a first sidewall portion that protrudes in a first direction from a side of the bottom surface, and a first support portion that protrudes from the first sidewall portion in a second direction that intersects with the first direction, and the second protrusion overlaps an outer surface of the first support portion. 
     In an exemplary embodiment, the assembly member includes a second sidewall portion that extends upward from the peripheral portion, where the second sidewall portion is in contact with an edge of the display panel. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view of a display device according to an exemplary embodiment. 
         FIGS. 2A and 2B  are perspective views of an assembly member of  FIG. 1 . 
         FIG. 3A  is a plan view of an assembly member. 
         FIG. 3B  is a side view of an assembly member. 
         FIGS. 4 to 11  illustrate a method of assembling a display device using the assembly member of  FIGS. 2A to 3B . 
         FIG. 12  is a perspective view of an assembly member according to another exemplary embodiment of  FIG. 1 . 
         FIG. 13A  is a plan view of an assembly member according to another exemplary embodiment. 
         FIG. 13B  is a side view of an assembly member according to another exemplary embodiment; 
         FIG. 14  is a perspective view of one corner of a bottom chassis according to another exemplary embodiment. 
         FIG. 15  is a cross-sectional view of a display device taken along line II-II′ of  FIG. 10  according to another exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     Embodiments of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the disclosure are shown. Embodiments of this disclosure may, however, take different forms and should not be construed as limited to exemplary embodiments set forth herein. 
     It will also be understood that when a layer is referred to as being “on” another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may also be present. The same reference numbers may indicate the same components throughout the specification. 
     Hereinafter, embodiments of the present disclosure will be described with reference to the attached drawings. 
       FIG. 1  is an exploded perspective view of a display device according to an exemplary embodiment. 
     Referring to  FIG. 1 , a display device  1  according to an exemplary embodiment of the present disclosure includes a top chassis  100 , a display panel  200 , and a backlight assembly  10 . The backlight assembly  10  includes an assembly member  300 , an optical member  500 , an optical film  400 , a light source module  600 , a reflective sheet  700 , a bottom chassis  800 , etc. The display panel  200  includes one of various light receiving display panels, such as a liquid crystal display panel, an electrowetting display panel, an electrophoretic display panel, or a microelectromechanical system display panel (MEMS display panel), etc. Hereinafter, an embodiment in which the display panel  200  is a liquid crystal display panel will be described as a non-limiting example. 
     According to an embodiment, the display panel  200  displays an image by adjusting an arrangement of liquid crystals that receive light from the backlight assembly  10  and refract the light in different patterns. The display panel  200  includes a thin film transistor substrate  210  on which a thin film transistor is formed, a color filter substrate  220  that faces the thin film transistor substrate  210 , and a liquid crystal layer interposed between the thin film transistor substrate  210  and the color filter substrate  220 . 
     According to an embodiment, the display panel  200  further includes a driving chip, a driving circuit film  230 , and a printed circuit board PB. The driving circuit film  230  is bent to electrically connect the display panel  200  and the printed circuit board PB. One end of the driving circuit film  230  is connected to one surface of the thin film transistor substrate  210 , and the other end thereof is connected to the printed circuit board PB. 
     According to an embodiment, the printed circuit board PB outputs signals to the display panel  200  or receives signals from the display panel  200  through the driving circuit film  230 . The printed circuit board PB is illustrated in  FIG. 1  as being disposed on the same plane as the display panel  200 , but may be disposed at various other positions according to a structure of the liquid crystal display device  1 . As the driving circuit film  230  is bent, the printed circuit board PB is disposed on a lower or side surface of the backlight assembly  10 . 
     According to an embodiment, the driving chip receives external signals and generates driving signals that drive the display panel  200 . The external signals are received from the printed circuit board PB. The external signals include a video signal, various control signals, a driving voltage, etc. The driving chip may be mounted on the driving circuit film  230 , the printed circuit board PB, or the thin film transistor substrate  210 . 
     According to an embodiment, the top chassis  100  includes an edge  110  that surrounds an edge of a lower long side of the display panel  200  and a top chassis sidewall  120  that extends toward the bottom chassis  800  from an outer perimeter of the edge. According to an exemplary embodiment, the top chassis  100  has a rectangular parallelepiped shape in which two surfaces that include a long side are omitted. The top chassis sidewall  120  couples to a sidewall  820  of the bottom chassis  800  using coupling portions such as a bolt and a nut, but embodiments of the present disclosure are not limited thereto. 
     According to an embodiment, the assembly member  300  guides edges of the display panel  200  and the optical member  500  and thus is fixedly coupled to the bottom chassis  800 . The assembly member  300  has a groove that couples to a panel support plate  830  of the bottom chassis  800  to be described below or attaches to the panel support plate  830  using double-sided tape. The assembly member  300  will be described in detail with reference to  FIGS. 2 and 3 , below. 
     According to an embodiment, a spacer tape ST is disposed between an edge region of the display panel  200  and the panel support plate  830 . Here, the spacer tape ST has a thickness sufficient to flatly support the display panel  200  supported by the assembly member  300  and the panel support plate  830 . The spacer tape ST includes a buffer member, a first adhesive layer disposed on one surface of the buffer member that attaches the buffer member and the display panel  200 , and a second adhesive layer disposed on the other surface of the buffer member that attaches the buffer member to the bottom chassis  800 . 
     According to an embodiment, the backlight assembly  10  is disposed on a rear of the display panel  200 . Here, a front of the display panel  200  refers to direction in which an image is displayed, and the rear of the display panel  200  refers to a direction opposite from the front direction. Hereinafter, a front or a front surface of an element refers to a direction in which the image is displayed, and a rear or a rear surface of the element refers to a direction opposite to the front direction. 
     According to an embodiment, the bottom chassis  800  has a space that accommodates the optical member  500 , the optical film  400 , the light source module  600 , and the reflective sheet  700 , etc. Specifically, the bottom chassis  800  includes a bottom surface  810 , the sidewall  820  that protrudes upward along an edge of the bottom surface  810 , and the support portion  830  that extends outward from the sidewall  820  parallel to the bottom surface  810 . The support portion  830  does not overlap the bottom surface  810  but overlaps the edge region of the display panel  200 . 
     According to an embodiment, the optical member  500  includes a light guide plate  510 , a wavelength conversion layer  520  disposed on the light guide plate  510 , and a passivation layer  530  disposed on the wavelength conversion layer  520 . The light source module  600  faces one side of the optical member  500 . For example, the light source module  600  is disposed adjacent to a light incidence surface  510   s  of the light guide plate  510  of the optical member  500 . The light source module  600  includes a plurality of point light sources or linear light sources. The point light source is a light-emitting diode (LED) light source  610 . A plurality of LED light sources  610  are mounted on a printed circuit board  620 . The LED light source  610  emits blue light. 
     In an exemplary embodiment, the LED light source  610  is a top-emitting LED that emits light through a top surface thereof. In this case, the printed circuit board  620  is disposed on an inner surface of the sidewall  820  of the bottom chassis such that the LEDs  610  emit light in a direction away from the sidewall  820  and into the light incidence surface  510   s  of the light guide plate  510 . 
     According to an embodiment, the blue light emitted from the LED light sources  610  is incident into the light guide plate  510 . The light guide plate  510  guides light and emits the light through an upper surface or a lower surface of the light guide plate  510 . The wavelength conversion layer  520  converts some of the blue light received from the light guide plate  510  into light having other wavelengths, such as green and red. The converted red and green light is emitted upward together with unconverted blue light toward the display panel  200 . 
     According to an embodiment, the reflective sheet  700  is disposed inside the bottom chassis  800 . For example, the reflective sheet  700  is disposed on an inner surface of the bottom plate  810  of the bottom chassis  800 . However, embodiments of the present disclosure are not limited thereto, and the reflective sheet  700  can be disposed along inner surfaces of the bottom plate  810  and the sidewall  820  of the bottom chassis  800 . 
     According to an embodiment, the reflective sheet  700  is disposed below the light guide plate  510  on a rear surface thereof and reflects light that has propagated out of the lower surface  510   b  of the light guide plate  510  back into the light guide plate  510  again. The reflective sheet  700  may be made of a plastic or a reflective metal, etc. 
     According to an embodiment, the light guide plate  510  guides the propagation of light. The light guide plate  510  has an overall polygonal plate shape. A planar shape of the light guide plate  510  may be rectangular, but embodiments are not limited thereto. In an exemplary embodiment, the light guide plate  510  may have a parallelepiped shape with a rectangular planar shape and may have an upper surface  510   a , a lower surface  510   b , shown in  FIGS. 10-11 , and four side surfaces  510 S. 
     In an exemplary embodiment, each of the upper surface  510   a  and the lower surface  510   b  of the light guide plate  510  are disposed on one plane. The plane on which the upper surface  510   a  is disposed is substantially parallel to the plane on which the lower surface  510   b  is disposed, and thus, the light guide plate  510  has an overall uniform thickness. However, embodiments of the present disclosure are not limited thereto, and the upper surface  510   a  or the lower surface  510   b  may each have a plurality of planes, or a plane of the upper surface  510   a  may intersect with a plane of the lower surface  510   b . For example, the light guide plate may have a wedge shape in which a thickness of the light guide plate  510  decreases from one side surface, such as a light incident surface, to the other side surface, such as an opposite surface, opposite to the one side surface. Furthermore, the lower surface  510   b  may gradually incline upwards from near the side surface, such as the light incident surface, to the other side surface, such as the opposite surface, for a predetermined distance, so that the thickness decreases. Then, the upper surface has a flat shape. 
     According to an embodiment, the planes of the upper surface  510   a  and the lower surface  510   b  each form an angle of about 90° with a plane of each side surface  510   s . In some exemplary embodiments, the light guide plate  510  has an inclined surface between the upper surface  510   a  and one side surface  510   s  and or between the lower surface  501   b  and one side surface  510   s . Hereinafter, an embodiment will be described in which the upper surface and the side surface meet directly to form an angle of about 90° without an inclined surface. 
     According to an embodiment, a scattering pattern is disposed on the lower surface  510   b  of the light guide plate  510 . The scattering pattern changes a propagation direction of light inside the light guide plate  510  through total reflection and outputs the light out of the light guide plate  510 . 
     In an exemplary embodiment, the scattering pattern is provided as a separate layer or pattern. For example, a pattern layer that includes a protrusion pattern or a concave groove pattern is formed, or a print pattern is formed on the lower surface  510   b  of the light guide plate  510  to function as the scattering pattern. 
     In another embodiment, the scattering pattern is a pattern of a surface of the light guide plate  510  itself. For example, concave grooves are formed on the lower surface  510   b  of the light guide plate  510  to function as the scattering pattern. 
     According to an embodiment, a pattern density of the scattering pattern varies according to regions. For example, a region adjacent to the light incidence surface having a relatively high light intensity has a low pattern density, and a region adjacent to the opposite surface having a relatively low light intensity has a high pattern density. 
     According to an embodiment, the light guide plate  510  is made of a light transmissive material, such as glass, quartz, or a polymer, etc., such that light is efficiently guided. For example, the polymer includes a material having a predetermined refractive index, such as an acrylic resin such as polymethyl methacrylate (PMMA) or polycarbonate (PC). 
     According to an embodiment, the wavelength conversion layer  520  is disposed on an upper surface of the light guide plate  510 . The wavelength conversion layer  520  converts a wavelength of at least a portion of the incident light. The wavelength conversion layer  520  includes a binder layer and wavelength conversion particles dispersed in the binder layer. The wavelength conversion layer  520  further includes scattering particles dispersed in the binder layer in addition to the wavelength conversion particles. 
     According to an embodiment, the binder layer is made of one or more various resin compositions, which are generally referred to as a binder, as a medium in which the wavelength converting particles are dispersed. However, embodiments of the present disclosure are not limited thereto, and in other embodiments, a medium referred to as the binder layer may include additional other functions or component materials, etc., as long as the medium can bind the wavelength conversion particles or the scattering particles. 
     According to an embodiment, the wavelength conversion particles convert a wavelength of incident light. For example, the wavelength conversion particles may be quantum dots (QDs), fluorescent materials, or phosphorescent materials. QDs will be described in detail as an example of wavelength conversion particles. A QD has a crystal structure with a size of few nanometers, includes hundreds to thousands of atoms, and exhibits a quantum confinement effect in which an energy band gap increases with decreasing size of the QD. When light having a wavelength with energy higher than that of the band gap is incident on a QD, the QD absorbs the light and transitions to an excited state, and decays back to a ground state by emitting light having a specific wavelength. The emitted light has a wavelength whose energy corresponds to the band gap. The size and composition of a QD can be adjusted to adjust emission characteristics due to the quantum confinement. 
     For example, according to an embodiment, a QD include at least one of a II-VI group compound, a II-V group compound, a III-VI group compound, a III-V group compound, a IV-VI group compound, or a II-IV-V group compound. 
     According to an embodiment, a QD includes a core and a shell that overcoats the core. However, embodiments of the present disclosure are not limited thereto. For example, the core includes at least one of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InP, InAs, InSb, SiC, Ca, Se, In, P, Fe, Pt, Ni, Co, Al, Ag, Au, Cu, FePt, Fe 2 O 3 , Fe 3 O 4 , Si, or Ge, and the shell includes at least one of ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, HgS, HgSe, HgTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, GaSe, InN, InP, InAs, InSb, TlN, TlP, TlAs, TlSb, PbS, PbSe, or PbTe. 
     According to an embodiment, there are a plurality of different types of wavelength conversion particles that convert incident light into light of different wavelengths. For example, the wavelength conversion particles include first wavelength conversion particles that convert incident light having a specific wavelength into light having a first wavelength, and second wavelength conversion particles that convert incident light having the specific wavelength into light having a second wavelength. In an exemplary embodiment, light emitted from the light source  610  and incident on the wavelength conversion particles is blue light, the first wavelength is a green wavelength, and the second wavelength is a red wavelength. For example, the blue wavelength has a peak wavelength of from 420 nm to 470 nm, the green wavelength has a peak wavelength of from 520 nm to 570 nm, and the red wavelength has a peak wavelength of from 620 nm to 670 nm. However, embodiments of the present disclosure are not limited to the disclosed peak wavelengths, and the blue, green, and the red wavelengths include all wavelength ranges capable of being perceived as blue, green, or red light. 
     In an exemplary embodiment, when blue light incident on the wavelength conversion layer  520  passes through the wavelength conversion layer  520 , a portion of the blue light incident on the first wavelength conversion particles is converted into and emitted as green light. Another portion of the blue light incident on the second wavelength conversion particles is converted into and emitted as red light. The remaining portion of the blue light is emitted from the wavelength conversion layer  520  without being incident on the first and second wavelength conversion particles. Accordingly, the light emitted from the wavelength conversion layer  520  includes the remaining portion of blue along with the green light and the red light. A ratio between different colored emitted light can be appropriately adjusted to display white light or different color light. Light converted by the wavelength conversion layer  520  has a sharp spectrum that is concentrated within a specific, narrow wavelength range and has a narrow full-width. Therefore, when light having such a spectrum is filtered by a color filter to impart a color, color reproducibility is improved. 
     However, unlike an above-described exemplary embodiment, in another embodiment, incident light is other short-wavelength light, such as ultraviolet light, and the wavelength conversion layer  520  includes three types of wavelength conversion particles that convert the incident light into blue light, green light, and red light, thereby emitting white light. 
     According to an embodiment, the wavelength conversion layer  520  further includes scattering particles. The scattering particles are not quantum dot particles and have no wavelength conversion function. The scattering particles scatter incident light so that more incident light is incident on the wavelength conversion particles. In addition, the scattering particles uniformly control an emission angle of light for each wavelength. Specifically, when a portion of light is incident on the wavelength conversion particles and then is converted and emitted as another wavelength, an emission direction of the emitted portion thereof is random. When scattering particles are not present in the wavelength conversion layer  520 , green light and red light emitted by the wavelength conversion particles have emission characteristics, but blue light that did not collide with the wavelength conversion particles does not have emission characteristics. Thus, a ratio of blue, green, and red wavelengths in the light will vary according to emission angles. The scattering particles impart scattering characteristics to blue light, thereby adjusting the light emission angles for each wavelength. TiO 2  or SiO 2 , etc., can be used as the scattering particles. 
     According to an embodiment, the passivation layer  530  is disposed on the wavelength conversion layer  520 . The passivation layer  530  prevents permeation of impurities such as moisture or oxygen. The passivation layer  530  is made of an inorganic material. For example, the passivation layer  530  includes at least of silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide or silicon oxynitride, or is formed as a metallic thin film that can transmit light. In an exemplary embodiment, the passivation layer  530  is made of silicon nitride. 
     According to an embodiment, the passivation layer  530  completely overlaps the wavelength conversion layer  520 , covers an upper surface of the wavelength conversion layer  520 , and further extends outward from the wavelength conversion layer  520  to also cover side surfaces of the wavelength conversion layer  520 . The passivation layer  530  contacts the upper and side surfaces of the wavelength conversion layer  520 . The passivation layer  530  extends to the upper surface of an edge of the light guide plate  510  exposed by the wavelength conversion layer  520 , and thus, a portion of an edge of the passivation layer  530  is in direct contact with the upper surface of the light guide plate  510 . In an exemplary embodiment, a side surface of the passivation layer  530  is aligned with a side surface of the light guide plate  510 . 
     According to an embodiment, the wavelength conversion layer  520  is sealed by the passivation layer  530 , etc., thereby preventing degradation of the wavelength conversion layer  520 . In addition, the wavelength conversion layer  520  and a sealing structure thereof reduce a manufacturing cost and a thickness of the optical member  500  as compared with a wavelength conversion layer provided as a separate film. 
     According to an embodiment, an optical film  400  is disposed between the optical member  500  and the display panel  200 . The optical film  400  is disposed on an upper surface of the optical member  500  and diffuses and condenses light emitted from the optical member  500 . 
     According to an embodiment, a plurality of optical films  400  are provided. The plurality of optical films  400  are stacked to overlap and complement each other. The optical film  400  includes a first film  410 , a second film  420 , and a third film  430  integrated with each other. In an exemplary embodiment, the first film  410  is a microlens pattern layer or a diffusion layer, the second film  420  is a prismatic pattern layer, and the third film  430  includes a reflective polarizing layer. 
     According to an embodiment, the plurality of optical films  400  will be described in more detail. First, the first film  410  is disposed between the optical member  500  and the second film  420  and disperses light received from the optical member  500  to prevent the incident light from being partially concentrated. The second film  420  includes a triangular prism arrangement on one surface thereof and condenses the light diffused by the first film  410  in a direction perpendicular to the display panel  200 . Finally, to improve luminance characteristics, the third film  430  transmits light received from the second film  420  that oscillates in the first direction and reflects the light received from the second film  420  that oscillates in a second direction perpendicular to the first direction. 
     According to an exemplary embodiment, the optical member  500  and the optical film  400  are coupled to each other by an optical member coupling layer. The optical member coupling layer is a film that has adhesive characteristics on both an upper surface and a lower surface thereof. For example, the optical member coupling layer may be a pressure sensitive adhesive (PSA), an optical clear adhesive (OCA), or an optical clear resin OCR. The optical member coupling layer includes one or more of acrylic resin or silicone resin, etc. 
       FIGS. 2A and 2B  are perspective views of an assembly member of  FIG. 1 .  FIG. 3A  is a plan view of an assembly member.  FIG. 3B  is a side view of an assembly member. 
     Referring to  FIGS. 2A, 2B, 3A, and 3B , according to an embodiment, the assembly member  300  includes a body  310 , two first protrusions  320 , and two second protrusions  330 . The body  310  of the assembly member  300  has one corner which forms a right angle. Each first protrusion  320  extends from one side of the body  310  and has a guide surface GS formed as a right angle θ in a plan view that guides the four corners of the optical member  500 . For clarity of illustration, only one of each of the first protrusions  320  and second protrusions  330  is labeled. To prevent the spacer tape ST from detaching, each second protrusion  330  extends from one side of the body  310  in directions perpendicular to each other and perpendicular to the extension direction of the first protrusion  320 . 
     According to an embodiment, the body  310  of the assembly member  300  includes an upper surface portion  311 , a sidewall portion  312 , a lower surface portion  313 , and a side surface portion  314 . 
     According to an embodiment, the upper surface portion  311  of the body  310  includes a support portion  311 _ c  which is formed as a right angle in a plan view and a peripheral portion  311 _ 3   s  disposed to be spaced apart from the support portion  311 _ c  and may have a first side  311 _ 1   s  and a second side  311 _ 2   s  which connect the support portion  311 _ c  and the peripheral portion  311 _ 3   s . According to an exemplary embodiment, the body  310  has a rectangular shape in a plan view, the support portion  311 _ c  is a region bent to an inner side of the rectangular shape, and the peripheral portion  311 _ 3   s  has a chamfered shape between two intersecting sides. The support portion  311 _ c  is in contact with a corner of the optical member  500  and supports the optical member  500  together with a side surface portion  322  of the first protrusion  320  to be described below. However, embodiments of the present disclosure are not limited thereto, and in other embodiments, a shape of the supporting portion  311 _ c  can vary according to a shape of the corner of the optical member  500  disposed adjacent thereto. For example, the supporting portion  311 _ c  may have a polygonal shape or an elliptical shape. 
     According to an embodiment, the sidewall portion  312  of the body  310  extends upward from the peripheral portion  311 _ 3   s  along the peripheral portion  311 _ 3   s . The sidewall portion  312  has an inner side surface  312 _ a  and an outer side surface  312 _ b  opposite to the inner side surface  312 _ a . According to an exemplary embodiment, the sidewall portion  312  forms a rounded corner in a plan view. To support the display panel  200 , the inner side surface  312 _ a  is in contact with a corner of the display panel  200 . When the display panel  200  has a frameless structure, the outer side surface  312 _ b  forms an exterior of a product. However, embodiments of the present disclosure are not limited thereto, and in other embodiments, a shape of the sidewall portion  312  can vary according to a shape of the corner of the display panel  200  disposed adjacent thereto. For example, the sidewall portion  312  may have a polygonal shape or an elliptical shape. A height of the sidewall portion  312  is greater than or equal to a thickness of the display panel  200  disposed adjacent thereto. 
     According to an embodiment, the side surface portion  314  of the body  310  extends downward from the upper surface portion  311 . A height of the side surface portion  314  is less than or equal to a height of the bottom chassis  800  coupled to the assembly member  300 . According to an exemplary embodiment, the bottom surface  810  of the bottom chassis  800  has a rectangular shape in a plan view. The sidewall  820  that extends upward from the bottom surface  810  is not formed in the four corner regions of the bottom chassis  800 . The side surface portion  314  of the body  310  is in contact with the sidewall  820  of the bottom chassis  800 . 
     According to an embodiment, the lower surface portion  313  of the body  310  is a surface opposite to the upper surface portion  311 . According to an exemplary embodiment, the assembly member  300  coupled to the bottom chassis  800  is coupled to an outer case, and the lower surface portion  313  is in contact with one surface of the case. However, embodiments of the present disclosure are not limited thereto, and in other embodiments, the lower surface portion  313  is omitted. In this case, the body  310  is hollow. 
     According to an embodiment, each of the first protrusions  320  of the assembly member  300  includes an upper surface portion  321  and a side surface portion  322 . 
     According to an embodiment, each of the upper surface portions  321  of the first protrusions  320  respectively extend from a portion of the first side  311 _ 1   s  and a portion of the second side  311 _ 2   s  of the body  310 . Each upper surface portion  321  has a first surface  321 _ a  and a second surface  321 _ b  opposite to the first surface  321 _ a . The first surface  321 _ a  forms one coplanar surface with the upper surface portion  311 . The first surface  321 _ a  and the upper surface portion  311  of the body  310  are in contact with a lower surface of the display panel  200 . The second surface  321 _ b  is in contact with an upper surface of the support portion  830  of the bottom chassis  800 . The second surface  321   b  couples to the support portion  830  of the bottom chassis  830  using a double-sided tape. 
     According to an embodiment, the side surface portion  322  of the first protrusion  320  extends downward from the upper surface portion  321 , parallel to the extension direction of the second protrusions  330 . The side surface portion  322  has a third surface  322 _ a  and a fourth surface  322 _ b  opposite to the third surface  322 _ a . The third surface  322 _ a  form one coplanar surface with the surface of the support portion  311 _ c . The third surface  322 _ a  and the surface of the support portion  311 _ c  are in contact with and overlap a corner surface of the optical member  500 . The fourth surface  322 _ b  is in contact with and overlaps a surface of the sidewall  820  of the bottom chassis  800 . The fourth surface  322 _ b  couples to the sidewall  820  of the bottom chassis  830  using a double-sided tape. 
     According to an embodiment, each second protrusion  330  of the assembly member  300  extends from the upper surface portion  311  and the sidewall portion  312  of the body  310  at the first side  311 _ 1   s  and the second side  311 _ 2   s  and is parallel to the side surface portion  322  of the second protrusion  320 . In the assembly member  300 , trench regions TR are formed in spaces between the body  310 , and the first protrusion  320  and the second protrusion  330  at the first side  311 _ 1   s  and the second side  311 _ 2   s . A width W 1  of the trench region TR is less than a width W 2  of the upper surface portion  321  of the first protrusion  320 , and a depth H 1  of the trench region TR is less than a length H 2  of the upper surface portion  321  of the first protrusion  320 . The width W 1  and the depth H 1  of the trench region TR can be freely varied within the range to prevent the spacer tape ST disposed adjacent thereto from detaching from the support portion  830  of the bottom chassis  800 . 
     According to an embodiment, the second protrusion  330  has a fifth surface  330 _ a  and a sixth surface  330 _ b  extending downward from the fifth surface  330 _ a . The fifth surface  330 _ a  of the second protrusion  330  forms one coplanar surface with the upper surface portion  311 . The fifth surface  330 _ a , the first surface  321 _ a , and the upper surface portion  311  of the body  310  are in contact with the lower surface of the display panel  200 . The sixth surface  330 _ b  of the second protrusion  330  is in contact with and overlaps a surface of the sidewall  820  of the bottom chassis  800 . 
       FIGS. 4 to 11  illustrate a method of assembling a display device using an assembly member of  FIGS. 2A to 3B . 
     Referring to  FIGS. 4 to 11 , according to an embodiment, a display device  1  has a structure in which a bottom chassis  800 , a reflective sheet  700 , an optical member  500 , an assembly member  300 , an optical film  400 , and a display panel  200  are sequentially stacked. In a method of assembling the display device  1 , first the bottom chassis  800  is provided. According to an exemplary embodiment, in the bottom chassis  800 , a bottom surface  810  of the bottom chassis  800  has a rectangular shape in a plan view. A sidewall  820  that protrudes upward from the bottom surface  810  protrudes higher along the sides of the bottom chassis than in the four corner regions of the bottom chassis  800 . The bottom chassis  800  includes a support portion  830  that extends outward from the sidewall  820  and parallel to the bottom surface  810 . 
     Referring to  FIG. 5 , according to an embodiment, an adhesive member AD 1  that couples the assembly member  300  to the bottom chassis  800  is attached to lower surfaces of the assembly member  300 . An upper surface portion  321  of the assembly member  300  has a first surface  321 _ a  and a second surface  321 _ b  opposite to the first surface  321 _ a . The second surface  321 _ b  is disposed in contact with an upper surface of the support portion  830  of the bottom chassis  800 . The second surface  321 _ b  couples to the support portion  830  of the bottom chassis  800  using the adhesive member AD 1  such as a double-sided tape. However, embodiments of the adhesive member AD 1  are not limited thereto, and in other embodiments, the adhesive member AD 1  is an adhesive layer applied onto the second surface  321 _ b . At least a portion of the adhesive member AD 1  attached to the lower surface  321 _ b  of the first protrusion  320  overlaps overlap a trench region TR. 
     Referring to  FIG. 6 , according to an embodiment, a plurality of assembly members  300  to which the adhesive member AD 1  is coupled are inserted into four corners of the bottom chassis  800 . The assembly members  300  are vertically pressed and assembled such that the upper surface portion  321  of the first protrusion  320  and the support portion  830  of the bottom chassis  800  couple to overlap each other, and a side surface portion  322  of the first protrusion  320  and the sidewall  820  of the bottom chassis  800  couple to overlap each other. A new corner that is disposed inward as compared with each of four corners of the bottom chassis  800  is formed by the plurality of assembly members  300  coupled to the bottom chassis  800 . That is, when the optical member  500  is disposed in the bottom chassis  800 , the optical member  500  will be spaced a distance apart from the sidewall  820  of the bottom chassis  800 . 
     Next, referring to  FIG. 7 , according to an embodiment, the optical member  500  is inserted into the bottom chassis  800 . When the assembly member  300  is coupled to each corner of the bottom chassis  800 , the optical member  500  can be vertically pressed and assembled to be inserted into the bottom chassis  800 . Here, four corners of the optical member  500  are disposed in contact with the new corners formed by the first protrusions  320  of the assembly members  300 . Thus, a bonding force between the bottom chassis  800  and the optical member  500  is sufficiently secured. 
     According to an embodiment, the optical film  400  is attached onto the optical member  500  and completely overlaps the optical member  500 . The optical member  500  and the optical film  400  are coupled to each other by an optical member coupling layer. The optical member coupling layer may be a film that has adhesive characteristics on both an upper surface and a lower surface thereof. For example, the optical member coupling layer may be a PSA, an OCA, or an OCR. The optical member coupling layer includes one of an acrylic resin or a silicone resin, etc. 
     According to an embodiment, a light source module  600  is inserted and faces one side of the optical member  500 . For example, the light source module  600  is disposed adjacent to a light incidence surface  510   s  of a light guide plate  510  of the optical member  500 . The light source module  600  includes a plurality of point light sources or linear light sources. The point light sources may be LED light sources  610 . A plurality of LED light sources  610  are mounted on a printed circuit board  620 . The LED light source  610  emits blue light. An aluminum bar AL is disposed between the printed circuit board  620  and the sidewall  820  of the bottom chassis  800 . A plurality of support members  630  that support one surface of the optical member  500  are formed between the printed circuit board  620  and the aluminum bar AL. The plurality of support members  630  protrude toward the optical member  500  between the LED light sources  610  and are formed in contact with one surface of the optical member  500 . Thus, it is possible to prevent the optical member  500  from being bent by gravity. 
     According to an embodiment, a spacer tape ST is attached onto the support portion  830  of the bottom chassis  800 . The spacer tape ST includes a buffer member, a first adhesive layer disposed on one surface of the buffer member to attach the buffer member and the display panel  200 , and a second adhesive layer disposed on the other surface of the buffer member to attach the buffer member and the bottom chassis  800 . The spacer tape ST on the support portion  830  of the bottom chassis  800  is partially covered by the first protrusion  320  of the assembly member  300 . As a result, a stepped portion is formed between the assembly member  300  and the bottom chassis  800 . Since the display panel  200  attaches onto the assembly member  300  and the bottom chassis  800 , the spacer tape ST has a thickness that is sufficient to compensate for the stepped portion between the assembly member  300  and the bottom chassis  800   
     According to an embodiment, in edge regions of the bottom chassis  800 , both ends of the spacer tape ST are formed along boundaries between the body  310 , and the first protrusion  320  and the second protrusion  330 . Specifically, both ends of the spacer tape ST extend into and are surrounded by trench regions TR of the assembly member  300 . Thereby, it is possible to prevent the spacer tape ST from detaching from the support portion  830  of the bottom chassis  800 . In addition, light emitted from the light source module  600  propagates in all directions, such as the direction of the display panel  200  and the direction of the sidewall  820  of the bottom chassis  800 . In this case, light propagating in the direction of the sidewall  820  of the bottom chassis  800 , which can causes a light leak, is reflected three or more times by the trench region TR of the assembly member  300 , and thus a phenomenon of light being unnecessarily visible outside the display device  1  can be considerably reduced. 
     Next, according to an embodiment, the display panel  200  is seated on the bottom chassis  800  to which the assembly member  300  is coupled. When the assembly member  300  is coupled to each corner of the bottom chassis  800 , the display panel  200  is vertically pressed and assembled to be seated in the bottom chassis. 
     According to an embodiment, a corner surface of the display panel  200  may be disposed such that an inner side surface  312   a  of a sidewall portion  312  of the assembly member  300  is in contact therewith. In addition, referring now to  FIG. 8 , an adhesive member AD 2  that couples one surface of the display panel  200  is disposed on a partial surface of the body  310  of the assembly member  300  and a first surface  321 _ a  of the first protrusion  320 . A planar shape of the adhesive member AD 2  is that of an “L” shape. However, embodiments of the present disclosure are not limited thereto, and in other embodiments, the adhesive member AD 2  is attached to an upper surface  311  of the body  300  of the assembly member  300  and an entire region of the first surface  321 _ a  of the first protrusion  320 . The first surface  321 _ a  is coupled to a surface of the display panel  200  using the adhesive member AD 2 , such as a double-sided tape. However, embodiments of the adhesive member AD 2  are not limited thereto, and in other embodiments, the adhesive member AD 2  is an adhesive layer applied on the first surface  321 _ a . As a result, it is possible to secure a sufficient bonding force with the bottom chassis  800  to which the display panel  200  and the assembly member  300  are coupled. 
     Referring to  FIG. 9 , according to an embodiment, the display panel  200  further includes a window WD. The window WD includes a transparent region DA_ 1  and a printed region NDA_ 1  that includes an opaque pigment that respectively overlap a display area DA and a non-display area NDA of the display panel  200 . An air layer V is provided between the display panel  200  and the optical film  400 , as shown in  FIGS. 10 and 11 .  FIG. 10  is a cross-sectional view taken along line II-II′ of  FIG. 9 , and  FIG. 11  is a cross-sectional view taken along line I-I′ of  FIG. 9 . 
     Hereinafter, other exemplary embodiments of an assembly member will be described. In the following exemplary embodiments, descriptions of the same configurations as those of the previously described exemplary embodiment will be omitted or simplified, and differences will be mainly described. 
       FIG. 12  is a perspective view of an assembly member according to another exemplary embodiment of  FIG. 1 .  FIG. 13A  is a plan view of an assembly member according to another exemplary embodiment.  FIG. 13B  is a side view of an assembly member according to another exemplary embodiment.  FIG. 14  is a perspective view of a corner of a bottom chassis according to another exemplary embodiment.  FIG. 15  is a cross-sectional view of a display device taken along line II-II′ of  FIG. 9  according to another exemplary embodiment. 
     Referring to  FIGS. 12 to 15 , according to an embodiment, an assembly member  300 _ 1  differs from the assembly member  300  shown in  FIGS. 2A to 3B  in that the assembly member  300 _ 1  further includes a third protrusion  323  that protrudes from a support portion  311 _ 1   c  of a body  310 _ 1  of the assembly member  300 _ 1  and a side surface portion  322  of a first protrusion  320 _ 1 , and a coupling hole  324  disposed in one region of the side surface portion  322 _ 1  of the first protrusion  320 _ 1 . 
     More specifically, according to an embodiment, the assembly member  300 _ 1  includes the body  310 _ 1 , two first protrusions  320 _ 1 , two second protrusions  330 _ 1 , and the third protrusion  323 . For clarity of illustration, only one of each of the first protrusions  320 _ 1  and second protrusions  330 _ 1  is labeled. The body  310 _ 1  of the assembly member  300 _ 1  has one corner that forms a right angle. Each first protrusion  320 _ 1  extends from one side of the body  310 _ 1  and has a guide surface GS formed as a right angle θ in a plan view that guides the four corners of the optical member  500 . To prevent the spacer tape ST from detaching, each second protrusion  330 _ 1  extends from one side of the body  310  in directions perpendicular to each other and perpendicular to the extension direction of the first protrusion  320 . The third protrusion  323  protrudes from the support portion  311 _ 1   c  of the body  310 _ 1  and the side surface portion  322 _ 1  of the first protrusion  320 _ 1 . 
     According to an embodiment, the body  310 _ 1  of the assembly member  300 _ 1  includes an upper surface portion  311 _ 1 , a sidewall portion  312 _ 1 , a lower surface portion, and a side surface portion  314 _ 1 . 
     According to an embodiment, the upper surface portion  311 _ 1  of the body  310 _ 1  includes the support portion  311 _ c  at a right angle in a plan view, and a peripheral portion  311 _ 13   s  spaced apart from the support portion  311 _ c  that has a first side  311 _ 11   s  and a second side  311 _ 12   s  which connect the support portion  311 _ c  and the peripheral portion  311 _ 13   s . According to an exemplary embodiment, the body  310 _ 1  has a rectangular shape in a plan view, the support portion  311 _ 1   c  is a region bent to an inner side of the rectangular shape, and the peripheral portion  311 _ 3   s  has a chamfered shape between two intersecting sides. The support  311 _ 1   c  is in contact with a corner of the optical member  500  and supports the optical member  500  together with the side surface portion  322 _ 1  of the first protrusion  320  to be described below. However, embodiments of the present disclosure are not limited thereto, and in other embodiments, a shape of the supporting portion  311 _ c  can vary according to a shape of the corner of the optical member  500  disposed adjacent thereto. For example, the sidewall portion  312  may have a polygonal shape or an elliptical shape. 
     According to an embodiment, sidewall portion  312 _ 1  of the body  310 _ 1  extends upward from the peripheral portion  311 _ 12   s  along the peripheral portion  311 _ 12   s . The sidewall portion  312 _ 1  has an inner side surface  312 _ 1   a  and an outer side surface  312 _ 1   b  opposite to the inner side surface  312 _ 1   a . According to an exemplary embodiment, the sidewall portion  312 _ 1  has a rounded corner in a plan view. To support the display panel  200 , the inner side surface  312 _ 1   a  is in contact with a corner of the display panel  200 . When the display panel  200  has a frameless structure, the outer side surface  312 _ 1   b  forms an exterior of a product. However, embodiments of the present disclosure are not limited thereto, and in other embodiments, a shape of the sidewall portion  312 _ 1  can vary according to a shape of the corner of the display panel  200  disposed adjacent thereto. For example, the sidewall portion  312 _ 1  may have a polygonal shape or an elliptical shape. A height of the sidewall portion  312 _ 1  is greater than or equal to a thickness of the adjacent display panel  200 . 
     According to an embodiment, the side surface portion  314 _ 1  of the body  310 _ 1  extends downward from the upper surface portion  311 _ 1 . A height of the side surface portion  314 _ 1  is less than or equal to a height of the bottom chassis  800  coupled to the assembly member  300 _ 1 . According to an exemplary embodiment, the bottom surface  810 _ 1  of the bottom chassis  800 _ 1  has a rectangular shape in a plan view. The sidewall portion  820 _ 1  that protrudes upward from the bottom surface  810 _ 1  protrudes higher along the sides of the bottom chassis than in the four corner regions of the bottom chassis  800 _ 1 . The side surface portion  314 _ 1  of the body  310 _ 1  is disposed in contact with the sidewall portion  820 _ 1  of the bottom chassis  800 _ 1 . 
     According to an embodiment, each first protrusion  320 _ 1  of the assembly member  300 _ 1  includes the upper surface portion  321 _ 1  and the side surface portion  322 _ 1 . 
     According to an embodiment, the upper surface portions  321 _ 1  of each first protrusion  320 _ 1  respectively extend from a portion of the first side  310 _ 11   s  and a portion of the second side  311 _ 12   s  of the body  310 _ 1 . Each upper surface portion  321 _ 1  has a first surface  321 _ 1   a  and a second surface  321 _ 1   b  opposite to the first surface  321 _ 1   a . The first surface  321 _ 1   a  forms one coplanar surface with the upper surface portion  311 _ 1 . The first surface  321 _ 1   a  and the upper surface portion  311 _ 1  of the body  310 _ 1  are in contact with a lower surface of the display panel  200 . The second surface  321 _ 1   b  is in contact with an upper surface of a support portion  830 _ 1  of the bottom chassis  800 _ 1 . The second surface  321 _ 1   b  couples to the support portion  830 _ 1  of the bottom chassis  800 _ 1  using an adhesive member AD 1  such as a double-sided tape. 
     According to an embodiment, the side surface portion  322 _ 1  of the first protrusion  320 _ 1  extends downward from the upper surface portion  321 _ 1 , parallel to the extension direction of the second protrusions  330 _ 1 . The side surface portion  322 _ 1  has a third surface  322 _ 1   a  and a fourth surface  322 _ 1   b  opposite to the third surface  322 _ 1   a . The third surface  322 _ 1   a  forms one coplanar surface with the one surface of the support portion  311 _ 1   c . The third surface  322 _ 1   a  and the surface of the support portion  311 _ 1   c  are in contact with and overlap a corner surface of the optical member  500 . The fourth surface  322 _ 1   b  is in contact with and overlaps a surface of the sidewall portion  820 _ 1  of the bottom chassis  800 _ 1 . 
     According to an embodiment, the coupling hole  324  is formed in a region of the side surface portion  322 _ 1 . The coupling hole  324  passes through the third surface  322 _ 1   a  and the fourth surface  322 _ 1   b . The coupling hole  324  is illustrated in  FIG. 12  as having a rectangular shape, but embodiments of the present disclosure are not limited thereto. In other embodiments, the coupling hole  324  may have one of a polygonal shape, an elliptical shape, or a circular shape, etc. A latch protrusion  821  formed in the sidewall portion  820 _ 1  of the bottom chassis  800 _ 1  to be described below is insertion-coupled to the coupling hole  324 . Thus, the coupling between the assembly member  300 _ 1  and the bottom chassis  800 _ 1  is further strengthened. On the other hand, the side surface portion  322 _ 1  further includes cutting regions at both sides of the coupling hole  324 . Thus, the coupling hole  324  can move left and right, and thus, the latch protrusion  821  can be more easily coupled to the coupling hole  324 . 
     According to an embodiment, the second protrusion  330 _ 1  of the assembly member  300 _ 1  extends from the upper surface portion  311 _ 1  and the sidewall portion  312 _ 1  of the body  310 _ 1  at the first side  311 _ 11   s  and the second side  310 _ 12   s  and is parallel to the side surface portion  322 _ 1  of the second protrusion  320 _ 1 . In the assembly member  300 _ 1 , trench regions TR are formed in spaces between the body  310 _ 1 , and the first protrusion  320 - 1  and the second protrusion  330 _ 1  at the first side  311 _ 11   s  and the second side  310 _ 21   s . A width W 1  of the trench region TR is less than a width W 2 _ 1  of the upper surface portion  321 _ 1  of the first protrusion  320 _ 1 , and a depth H 1  of the trench region TR is less than a length H 2  of the upper surface portion  321 _ 1  of the first protrusion  320 _ 1 . The width W 1  and the depth H 1  of the trench region TR can be freely varied within the range to prevent the spacer tape ST from detaching from the support portion  830 _ 1  of the bottom chassis  800 _ 1 . 
     According to an embodiment, the second protrusion  330 _ 1  has a fifth surface  330 _ 1   a  and a sixth surface  330 _ 1   b  that extend downward from the fifth surface  330 _ 1   a . The fifth surface  330 _ 1   a  of the second protrusion  330 _ 1  forms one coplanar surface with the upper surface portion  311 _ 1 . The fifth surface  330 _ 1   a , first surface  321 _ 1   a  and the upper surface portion  311 _ 1  of the body  310 _ 1  are in contact with a lower surface of the display panel  200 . The sixth surface  330 _ 1   b  of the second protrusion  330 _ 1  is in contact with and overlaps a surface of the sidewall portion  820 _ 1  of the bottom chassis  800 _ 1 . 
     According to an embodiment, the third protrusion  323  protrudes from a surface of the support portion  311 _ 1   c  of the body  310 _ 1  and the side surface portions  322 _ 1  of the first protrusions  320 _ 1 . The third protrusion  323  has a seventh surface  323 _ a  and an eighth surface  323 _ b  opposite to the seventh surface  323 _ a . The seventh surface  323 _ a  is in contact with a surface of an edge of the optical member  500 _ 1 . The eighth surface  323 _ b  is in contact with a surface of an edge of the optical film  400 _ 1 . In addition, the optical film  400 _ 1  couples to the third protrusion  323  using an adhesive member such as a double-sided tape or couples to the third protrusion  323  using a latch protrusion or a coupling hole. An air layer V 1  is further provided between the optical film  400 _ 1  and the optical member  500 _ 1 . 
     In concluding the detailed description, those skilled in the art will appreciate that many variations and modifications can be made to exemplary embodiments without substantially departing from the principles of the present disclosure. Therefore, exemplary embodiments of the disclosure are used in a generic and descriptive sense only and not for purposes of limitation.