Abstract:
An apparatus includes a chassis assembly; a liquid crystal display panel; a light guide plate configured to guide light to the liquid crystal display panel; a light emitting diode (LED) module including a printed circuit board (PCB), a plurality of LED packages which are mounted on the PCB and emit light to a lateral side of the light guide plate, and a connector connected to the PCB such that the connector is located behind the light guide plate; and a white strip member disposed between the PCB of the LED module and the light guide plate. An edge portion of a bottom surface of the light guide plate is supported by the PCB.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. application Ser. No. 13/551,840 filed Jul. 18, 2012, which is a continuation of U.S. application Ser. No. 13/418,925 filed Mar. 13, 2012, which claims priority from Korean Patent Application No. 10-2011-0023402, filed Mar. 16, 2011 in the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference in their entireties. 
     
    
     BACKGROUND 
       [0002]    1. Field 
         [0003]    Apparatuses and methods consistent with exemplary embodiments relate to a liquid crystal display (LCD), and more particularly, to an LCD including a light emitting diode (LED) module having an improved structure. 
         [0004]    2. Description of the Related Art 
         [0005]    An LCD is an electronic device configured to change electrical information generated by various devices into the visual information and to provide the visual information. The LCD requires a backlight due to the lack of the light emitting ability, but is widely used as a flat panel display because of low power consumption and superior portability. 
         [0006]    The LCD uses a backlight unit as a light source for a liquid crystal that represents an image. The backlight unit is provided in variety of sizes and configurations, but in general, includes a lamp serving as a light source, an optical subsidiary member including a reflection sheet, a light guide plate, a diffusion sheet, a prism sheet and a protective sheet, and a mold frame serving as a support structure. 
         [0007]    The light source is implemented using a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp (EEFL), an LED, etc. 
         [0008]    In particular, a narrow bezel display having an LED as a light source has gathered a large amount of interest due to its differentiated design. 
       SUMMARY 
       [0009]    Exemplary embodiments provide a structure of an LED module capable of implementing a super narrow bezel. 
         [0010]    In accordance with an aspect of an exemplary embodiment, there is provided an LCD including a cover assembly, a liquid crystal panel, a light guide plate, a printed circuit board (PCB), and an LED. The light guide plate is configured to guide light to the liquid crystal panel. The light guide plate is mounted to the PCB. The LED package is mounted on the PCB and emits light to a lateral side of the light guide plate. The PCB includes a base substrate, a connecting hole, an insulating layer and a spacer taper. The connecting hole is formed in the base substrate to couple the base substrate to the cover assembly through a connecting member. The insulating layer is coated on the base substrate while avoiding a head part of the connecting member. The spacer tape is provided on an upper side of the insulating layer such that the light guide plate is evenly mounted on the PCB. 
         [0011]    The connecting member may be coupled downward to the PCB from an upper side to a lower side of the PCB. 
         [0012]    The cover assembly may include a top sash, a middle mold, and a bottom sash, wherein the PCB is coupled to the bottom sash. 
         [0013]    The LED package may be provided in a side view type LED package that is mounted on one side of an upper surface of the PCB to emit light toward an opposite side of the upper surface of the PCB. 
         [0014]    The LED package may include a lead terminal configured to receive power, and the PCB further comprises a lead terminal accommodating groove configured to accommodate the lead terminal. 
         [0015]    The insulating layer may include photo solder resist (PSR). 
         [0016]    The spacer tape may have a thickness substantially corresponding to a thickness of the head part of the connecting member. 
         [0017]    The spacer taper may be provided on the upper side of the insulating layer except for an area corresponding to one end portion of the PCB. 
         [0018]    An upper side of the insulating layer where the spacer tape is not provided may be coated with a black silk pattern. 
         [0019]    The LCD may further include a connector protruding from a lower surface of the PCB to connect the PCB to an external power source. 
         [0020]    The connector may be disposed at an edge of the PCB. 
         [0021]    The LCD further may include a white tape provided on an upper side of the spacer tape while being disposed between the LED package and the light guide plate. 
         [0022]    In accordance with an aspect of another exemplary embodiment, there is provided an LCD including a liquid crystal panel, a top sash, a light guide plate, an LED module, a bottom sash and a connecting member. The top sash includes a bezel configured to cover a rim of the liquid crystal panel. The light guide plate is configured to guide light to the liquid crystal panel. The LED module emits light to a lateral side of the light guide plate and supports the light guide plate such that the light guide plate is disposed at a position corresponding to an end portion of the bezel. The bottom sash is coupled to a lower side of the LED module to support the LED module. The connecting member is secured downward to couple the LED module to the bottom sash. 
         [0023]    The LED module may further include a PCB and an LED package. The light guide plate may be mounted on the PCB. The PCB is coupled to the bottom sash. The LED package may be mounted on one side of an upper surface of the PCB to emit light toward an opposite side of the upper surface of the PCB. 
         [0024]    The PCB may include a PSR coated for insulation. The PSR is coated while avoiding a head part of the connecting member. 
         [0025]    A spacer tape may have a thickness substantially identical to a thickness of the head part of the connecting member is provided on the PCB. 
         [0026]    In accordance with an aspect of another exemplary embodiment, there is provided an LED module including a PCB and an LED package. The LED package is provided in a side view type LED package that is mounted on one side of an upper surface of the PCB to emit light toward an opposite side of the upper surface of the PCB. The PCB includes a base substrate, a connecting hole, an insulating layer and a spacer tape. The connecting hole is formed through an upper surface and a lower surface of the base substrate to enable a connecting member to be coupled to the base substrate. The insulating layer is coated on the base substrate while being spaced apart outward from a circumference of the connecting hole by a predetermined distance. The spacer tape is provided on an upper side of the insulating layer to form a difference in steps around the connecting hole. 
         [0027]    The LED module may further include a lead terminal and a lead terminal accommodating groove. The lead terminal is formed on the LCD package to provide the LCD package with power. The lead terminal accommodating groove is formed in the PCB to accommodate the lead terminal. 
         [0028]    The LED module may further include a connector protruding from a lower surface of the PCB to connect the PCB to an external power source. 
         [0029]    The LED module may further include a white tape provided on an upper side of the spacer tape while being adjacent to the LED package. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]    The above and/or other aspects will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which: 
           [0031]      FIG. 1  is an exploded perspective view illustrating an LCD according to an exemplary embodiment; 
           [0032]      FIG. 2  is a perspective view illustrating a liquid crystal module of the LCD of  FIG. 1 ; 
           [0033]      FIG. 3  is an exploded perspective view of the liquid crystal module of  FIG. 2 ; 
           [0034]      FIG. 4  is a cross-sectional view of the liquid crystal module of  FIG. 2 ; 
           [0035]      FIG. 5  is a perspective view of the LED module of  FIG. 3 ; 
           [0036]      FIG. 6  is a top view of the LED module of  FIG. 3 ; 
           [0037]      FIG. 7  is a cross-sectional view enlarging a portion of the LED module of  FIG. 3 ; 
           [0038]      FIG. 8  is a top view enlarging a portion of the LED module of  FIG. 3 ; 
           [0039]      FIG. 9  is a side view of the LED module of  FIGS. 3 ; and 
           [0040]      FIG. 10  is a cross-sectional view taken along line I-I of the LED module of  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION 
       [0041]    Certain exemplary embodiments are described in detail below, with reference to the accompanying drawings. 
         [0042]    In the following description, like drawing reference numerals are used for the like elements, even in different drawings. The matters defined in the description, such as detailed construction and elements, are provided to assist in a comprehensive understanding of exemplary embodiments. However, exemplary embodiments can be carried out without those specifically defined matters. Also, well-known functions or constructions are not described in detail since that would obscure the invention with unnecessary detail. 
         [0043]      FIG. 1  is an exploded perspective view illustrating an LCD according to an exemplary embodiment.  FIG. 2  is a perspective view illustrating a liquid crystal module of the LCD of  FIG. 1 .  FIG. 3  is an exploded perspective view of the liquid crystal module of  FIG. 2 .  FIG. 4  is a cross-sectional view of the liquid crystal module of  FIG. 2 . 
         [0044]    Referring to  FIGS. 1 to 4 , an LCD  1  includes a front cover  3 , a liquid crystal module  10 , a main substrate  2 , and a rear cover  4 . The main substrate  2  operates the liquid crystal module  10  by applying signals to the liquid crystal module  10 . The front cover  3  and the rear cover  4  are disposed on a front side and a rear side of the liquid crystal module  10 , respectively, to cover and support the liquid crystal module  10  and the main substrate  2 . 
         [0045]    The liquid crystal module  10  includes a liquid crystal panel  20 , a backlight unit  70 , and a cover (chassis) assembly  30  that covers and supports the liquid crystal panel  20  and the backlight unit  70 . 
         [0046]    The liquid crystal panel  20  corresponds to a display area of the liquid crystal module  10 . Although not shown in the drawings, the liquid crystal panel  20  includes two thin glass substrates, liquid crystal molecules interposed between the two thin glass substrates, and a transparent electrode configured to apply a voltage to the liquid crystal molecules. 
         [0047]    The backlight unit  70  is disposed on a lower side of the liquid crystal panel  20  to emit light to the liquid crystal panel  20 , and includes an LED module  110 , a reflection sheet  100 , a light guide plate  90 , and an optical sheet  80 . It should be noted that the description of the components is illustrative only and is provided with reference to the drawings. Thus, the components which are described as upper or lower may be disposed on the front side of the display or on the rear side of the display, respectively, or vice versa. 
         [0048]    The light guide plate  90  is provided in the form of a hexahedron, and includes acryl-based resin. 
         [0049]    Various patterns are formed on a bottom surface of the light guide plate  90 . Such a pattern frustrates the total reflection of light introduced to a lateral side of the light guide plate  90 , so that the light is uniformly emitted through an upper surface of the light guide plate  90 . 
         [0050]    The reflection sheet  100  is provided on a lower side of the light guide plate  90  to reflect light, which travels downward after going through total reflection in the light guide plate  90 , toward the light guide plate  90 . 
         [0051]    The optical sheet  80  includes a protective sheet  81 , a prism sheet  82 , and a diffusion sheet  83 . 
         [0052]    The diffusion sheet  83  is provided on an upper side of the light guide plate  90  such that light emitted through the upper surface of the light guide plate  90  is diffused and provided to the liquid crystal panel  20 . The diffusion sheet  83  may be provided with a coating layer (not shown) having beads that diffuse light. 
         [0053]    The prism sheet  82  is configured to collect light, which is diffused through the diffusion sheet  83 , in a direction perpendicular to a display surface of the liquid crystal panel  20 . 
         [0054]    The protective sheet  81  is provided on an upper side of the prism sheet  82  to protect the prism sheet  82  susceptible to scratching due to dust. 
         [0055]    The LED module  110  includes a PCB  130  and an LED package  120  mounted on the PCB  130 , and emits light to the light guide plate  90 . According to the current exemplary embodiment, a pair of LED modules  110  is disposed on a left side and a right side of the liquid crystal module  10  in symmetry to each other, but the configuration of the LED module  110  is not limited thereto. Alternatively, a pair of LED modules  110  may be disposed on an upper side and a lower side of the liquid crystal module  10 . Alternatively, the LCD  1  may include only one LED module  110  provided on a lateral side of the liquid crystal module  10 . The configuration of the LED module  110  is described in detail below. 
         [0056]    The cover assembly  30  is configured to cover and support the liquid crystal panel  20  and the backlight unit  70 , and includes a top sash (chassis)  40 , a middle mold  50 , and a bottom sash (chassis)  60 . 
         [0057]    The top sash  40  includes a bezel  41  forming a rim of the liquid crystal module  10 , and a top lateral side wall  42 . An end portion  43  of the bezel  41  is disposed perpendicular to a lateral side of the light guide plate  90  or a lateral side of the optical sheet  80 . 
         [0058]    The bezel  41  may be a super narrow bezel having a length less than about 15 mm. 
         [0059]    The bottom sash  60  includes a bottom part  61  to support the reflection sheet  100 , the light guide plate  90  and the optical sheet  80 , a substrate accommodating part  62  to accommodate the LED module  110 , a bottom-lateral side wall  64 , and a connector passing part  63  allowing a connector to pass therethrough. 
         [0060]    The substrate accommodating part  62  is formed by recessing both end portions of the bottom part  61  to accommodate the LED module  110 . 
         [0061]    A connector  200  provided on a lower side of the LED module  110  is exposed to the outside of the liquid crystal module  10  by passing through the connector passing part  63 . 
         [0062]    The middle mold  50  includes a middle-lateral side wall  52  and a support part  51 . 
         [0063]    The middle-lateral side wall  52  has an upper side, which comes into close contact with the bezel  41  of the top sash  40 , and a lower side, which comes into close contact with the PCB  130  of the LED module  110 . 
         [0064]    The support part  51  is disposed between the liquid crystal panel  20  and the optical sheet  80  such that the liquid crystal panel  20  is spaced apart from the optical sheet  80  by a predetermined distance. The support part  51  has an upper side, which comes into close contact with the liquid crystal panel  20 , and a lower side, which comes into close contact with the optical sheet  80 , to stably support the liquid crystal panel  20  and the optical sheet  80 . 
         [0065]    Such a configuration of the cover assembly  30  is assembled by coupling the top lateral side wall  42  of the top sash  40  to the bottom lateral side wall  64  of the bottom sash  60  with a second connecting member (S 2 ). 
         [0066]      FIG. 5  is a perspective view of the LED module of  FIG. 3 .  FIG. 6  is a top view of the LED module of  FIG. 3 .  FIG. 7  is a cross-sectional view enlarging a portion of the LED module of  FIG. 3 .  FIG. 8  is a top view enlarging a portion of the LED module of  FIG. 3 .  FIG. 9  is a side view of the LED module of  FIG. 3 .  FIG. 10  is a cross-sectional view taken along line I-I of the LED module of  FIG. 6 . 
         [0067]    The configuration of the LED module  110  is described below with reference to  FIGS. 1 to 10 . 
         [0068]    The LED module  110  includes the PCB  130  to which the light guide plate  90  is mounted, and the LED package  120  mounted on an upper surface of the PCB  130 . 
         [0069]    In order to implement a super narrow bezel, the LED package  120  includes a side view type LED packages in which a light-emitting surface  122  is formed on a lateral side of a package body  121  of the LED package  120 . 
         [0070]    The liquid crystal module  10  uses a plurality of LED packages  120  that are mounted in line on one side of the upper surface of the PCB  130  to emit light to an opposite side of the upper surface of the PCB  130 . 
         [0071]    Referring to  FIG. 10 , a lead terminal  123  is formed on a leg part  124  extending downward from the package body  121  of the LED package  120  such that power is provided to the LED package  120 . In addition, a lead terminal accommodating groove  133  is formed in the PCB  130  to accommodate the lead terminal  123  such that the lead terminal  123  is prevented from being exposed to the outside, thereby preventing the LED package  120  from causing a short circuit due to foreign substances having electric conductivity. 
         [0072]    The PCB  130  includes a base substrate  140 , an insulating layer  150  coated on the base substrate  140 , a spacer tape  160  provided on an upper side of the insulting layer  150 , a white tape  180  provided on an upper side of the spacer tape  160 , a connecting hole  170  allowing the base substrate  140  to be coupled to the substrate accommodating part  62  of the bottom sash  60 , and the connector  200 . 
         [0073]    The base substrate  140  is formed using metal such as aluminum. Accordingly, heat generated from the LED package  120  is rapidly transmitted through the base substrate  140  and heat exchange is generated with the outside or outdoor air. In addition, although not shown in the drawings, the base substrate  140  is patterned with a wire that is connected to the lead terminal  123  of the LED package  120  such that the driving signals are transmitted to each of the LED packages  120 . 
         [0074]    A first connecting member (S 1 ) is inserted downward into the connecting hole  170  such that the base substrate  140  is coupled to the substrate accommodating part  62  of the bottom sash  60 . 
         [0075]    The first connecting member (S 1 ) includes a body part (B) having a screw thread and a head part (H) provided on an upper side of the body part (B). Since the first connecting member (S 1 ) is inserted downward into the connecting hole  170 , the head part (H) is provided inside the liquid crystal module  10  without being exposed to the outside of the liquid crystal module  10 . 
         [0076]    The base substrate  140  is coated with the insulating layer  150  for electric insulation. The insulating layer  150  is formed using a white PSR. 
         [0077]    The insulating layer  150  is coated while avoiding the head part (H) of the first connecting member (S 1 ). 
         [0078]    Referring to  FIGS. 7 and 8 , the insulating layer  150  is coated outside of a circular area having a diameter identical to that of a diameter (D 1 ) of the head part (H). That is, the insulating layer  150  is coated on an area of the base substrate  140  while being spaced apart from a circumference  171  of the connecting hole  170  by a predetermined distance (D 2 ). Accordingly, the head part (H) of the first connecting member (S 1 ) comes into close contact with the base substrate  140 . 
         [0079]    Such a partial coating reduces a difference in steps caused by the head part (H) of the connecting member (S 1 ) without an additional process. 
         [0080]    Referring to  FIG. 7 , the spacer tape  160  is provided on the upper side of the insulating layer  150 . The spacer tape  160  has a thickness (T 2 ) substantially identical to a thickness (T 1 ) of the head part (H) of the first connecting member (S 1 ). Since a thickness (T 3 ) of the insulting layer  150  is substantially less than the thickness (T 2 ) of the spacer tape  160 , the thickness (T 1 ) of the head part (H) is regarded to be substantially identical to the thickness (T 2 ) of the spacer tape  160 . 
         [0081]    The installation of the spacer tape  160  forms a difference in steps, which corresponds to the thickness (T 1 ) of the head part (H) of the first connecting member (S 1 ), around the connecting hole  170 . 
         [0082]    Accordingly, when the first connecting member (S 1 ) is fastened to the connecting hole  170 , the light guide plate  90  and the reflection sheet  100  are prevented from being slanted due to protruding of the head part (H) while maintaining a flat state. 
         [0083]    In addition, the connector  200  is provided to protrude on a lower side of the PCB  130 , thereby preventing the light guide plate  90  from being slantingly mounted on the PCB  130  due to the connector  200 . Further, the connector  200  is disposed at an edge of the PCB  130  to improve the assembling efficiency of the LED module  110 . 
         [0084]    An end portion  190  of the PCB  130  has a hole  131  to which an additional connecting member is coupled such that the coupling force between the PCB  130  and the bottom sash  60  is improved. The forming of the hole  131  reduces an area of the end portion  190  of the PCB  130  and therefore the end portion  190  of the PCB  130  having the hole  131  is too small to have the spacer tape  160  attached to the PCB  130 , and as a result the spacer tape  160  may be easily separated. Accordingly, the spacer tape  160  is not provided on the end portion  190  of the PCB  130  having the hole  131 . 
         [0085]    However, in order to prevent the liquid crystal panel  20  from having a light bouncing which is caused when the white PSR of the insulating layer  150  is exposed due to nonexistence of the spacer tape  160  on the end portion  190  of the PCB  130 , a black silk pattern is coated on the end portion  190  of the PCB  130  which does not accompany the spacer tape  160 . 
         [0086]    In general, the coating of the silk pattern is performed to pattern a predetermined symbol on an upper side of the insulating layer  150 . Accordingly, by performing such a general silk patterning on the end portion  190  which does not have the spacer tape  160 , the light bouncing is prevented and a bright portion is reduced without an additional process. 
         [0087]    A white tape  180  is provided on the upper side of the spacer tape  160  while being disposed between the LED package  120  and the light guide plate  90  to allow light emitted from the LED package  120  to be effectively introduced to the light guide plate  90 . The white tape  180  improves 10% or more of light introduction efficiency. 
         [0088]    As described above, a design differentiation is provided by implementing a super narrow bezel. In addition, this exemplary embodiment of a LCD and an LED module is implemented by using only a conventional process without an additional process, thereby enabling mass production. 
         [0089]    The foregoing exemplary embodiments and advantages are merely exemplary and are not to be construed as limiting. The present teaching can be readily applied to other types of apparatuses. Also, the description of the exemplary embodiments is intended to be illustrative, and not to limit the scope of the claims, and many alternatives, modifications, and variations will be apparent to those skilled in the art.