Abstract:
An exemplary LCD device ( 2 ) includes a liquid crystal display panel ( 21 ) and a housing assembly ( 23 ). The LCD panel includes a first substrate ( 211 ), a second substrate ( 213 ) parallel to the first substrate, and a polarizer ( 215 ) attached on the first substrate. The housing assembly is arranged for holding the liquid crystal display. The housing assembly includes a bezel ( 231 ). The bezel includes at least one bead portion ( 25 ) adjacent to an inner free edge thereof. The at least one bead portion elastically contacts a peripheral edge area of the first substrate, and the inner free edge of the bezel covers a peripheral edge portion of the polarizer.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is related to, and claims the benefit of, a foreign priority application filed in Taiwan as Serial No. 095141777 on Nov. 10, 2006. The related application is incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The present invention relates to liquid crystal display (LCD) devices, and particularly to an LCD device with a bezel having one or more bead portions. 
     BACKGROUND 
     A typical liquid crystal display (LCD) device is capable of displaying a clear and sharp image through thousands or even millions of pixels that make up the complete image. The LCD device has thus been applied to various electronic equipment in which messages or pictures need to be displayed, such as mobile phones and notebook computers. However, liquid crystal in the LCD device does not emit light itself. Rather, the liquid crystal has to be lit up by a light source so as to clearly and sharply display text and images. The light source may be ambient light, or a backlight module attached to the LCD device. 
       FIG. 8  is a schematic, top plan view of a typical LCD device. The LCD device  1  includes an LCD panel  11  and a housing assembly  13 . 
     Referring also to  FIG. 9 , this is a cross-sectional view taken along line IX-IX of  FIG. 8 . The LCD panel  11  includes a first substrate  111 , a second substrate  113  parallel to the first substrate  111 , and a polarizer  115  attached on a major portion of a top surface of the first substrate  111 . A margin portion of the top surface of the first substrate  111  is not covered by the polarizer  115 . A plurality of driver integrated circuits (ICs)  1130  is mounted on a margin portion of a top surface of the second substrate  113 . The housing assembly  13  includes a bezel  131  and a rear frame  133  for cooperatively containing and protecting the LCD panel  11 . The rear frame  133  defines a space for housing the LCD panel  11  and a backlight module (not labeled) under the LCD panel  11 . The bezel  131  includes four top walls  1313  arranged end to end, and four sidewalls  1311  perpendicularly extending from edges of the four top walls  1313 , respectively. The four top walls  1313  press on the margin portion of the top surface of the first substrate  111  of the LCD panel  11  and a top of the rear frame  133 . The four sidewalls  1311  enclose sidewalls of the rear frame  133 . Thus, the LCD panel  11  is fixed in the housing assembly  13 . 
     Typically, a small horizontal gap L 1  exists between each top wall  1313  of the bezel  131  and the polarizer  115 , in order to prevent the polarizer  115  from being distorted or damaged. However, if the gap L 1  is too large, light beams from the backlight module leak out from the gap. This is liable to result in bright lines or other optical defects. On the other hand, if the gap L 1  is eliminated and the top walls  1313  directly contact the polarizer  115 , the bezel  131  is liable to distort or damage the polarizer  115 . This is liable to cause mottling or other optical defects. 
     Accordingly, what is needed is an LCD device that can overcome the above-described deficiencies. 
     SUMMARY 
     In one aspect, an LCD device includes a liquid crystal display panel and a housing assembly. The LCD panel includes a first substrate, a second substrate parallel to the first substrate, and a polarizer attached on the first substrate. The housing assembly is arranged for holding the liquid crystal display. The housing assembly includes a bezel. The bezel includes at least one bead portion adjacent to an inner free edge thereof. The at least one bead portion elastically contacts a peripheral edge area of the first substrate, and the inner free edge of the bezel covers a peripheral edge portion of the polarizer. 
     In another aspect, an LCD device includes an LCD panel and a bezel configured for fixing the LCD panel therein. The bezel includes an elongate bead portion protruding toward and resiliently pressing on a peripheral edge area of the LCD panel. 
     In still another aspect, an LCD device includes an LCD panel, a polarizer attached on the LCD panel, and a bezel elastically pressing on a peripheral edge area of the LCD panel and fixing the LCD panel in position. The bezel includes an elongate supporting structure adjacent to an end of the bezel. The supporting structure is arranged between the bezel and the peripheral edge area of the LCD panel to maintain a gap therebetween. A peripheral portion of the polarizer extends into the gap. 
     Other novel features and advantages will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. In the drawings, all the views are schematic. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top plan view of an LCD device according to a first embodiment of the present invention, the LCD device including an LCD panel and a housing assembly for holding the LCD panel. 
         FIG. 2  is a side, cross-sectional view taken along line II-II of  FIG. 1 . 
         FIG. 3  is an enlarged view of a circled portion III of  FIG. 2 . 
         FIG. 4  is a top plan view of an LCD device according to a second embodiment of the present invention. 
         FIG. 5  is a side, cross-sectional view taken along line V-V of  FIG. 4 . 
         FIG. 6  is a top plan view of an LCD device according to a third embodiment of the present invention. 
         FIG. 7  is a top plan view of an LCD device according to a fourth embodiment of the present invention. 
         FIG. 8  is a top plan view of a conventional LCD device, the LCD device including an LCD panel and a housing assembly for holding the LCD panel. 
         FIG. 9  is a side, cross-sectional view taken along line IX-IX of  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Reference will now be made to the drawings to describe embodiments of the present invention in detail. 
     Referring to  FIG. 1 , this is a schematic, top plan view of an LCD device  2  according to a first embodiment of the present invention. The LCD device  2  includes an LCD panel  21 , and a housing assembly  23  for holding the LCD panel  21 . 
     Also referring to  FIG. 2 , this is a cross-sectional view taken along line II-II of  FIG. 1 . The LCD panel  21  includes a first substrate  211 , a second substrate  213  parallel to the first substrate  211 , and a polarizer  215  attached on a top surface  2111  of the first substrate  211 . An uncovered edge area of the top surface  2111  of the first substrate  211  defines a peripheral fixing area  2113 . The second substrate  213  defines at least one mounting area  2133  at least one side of a tope surface thereof.  FIG. 2  shows one mounting area  2133 . A plurality of driver integrated circuits (ICs)  217  are mounted on the mounting area  2133 . 
     The housing assembly  23  includes a rear frame  233  and a bezel  231  cooperatively receiving and securing the LCD panel  21 . The rear frame  233  is usually made of plastic and defines a receiving space. The receiving space is for receiving the LCD panel  21  and other components such as a backlight module. The bezel  231  is usually made of metal or another material with high mechanical strength. The bezel  231  includes four top walls  2313  arranged end to end, and four sidewalls  2311  perpendicularly extending from edges of the four top walls  2313 , respectively. The four top walls  2313  press on peripheral edge portions of the LCD panel  21  and a top of the rear frame  233 , and the four sidewalls  2311  encircle the rear frame  233 , so that the LCD panel  21  is tightly fixed in the housing assembly  23 . 
     Each of the four top walls  2313  includes a bead portion  25  near a free edge thereof. The bead portion  25  has a generally U-shaped cross-section. The four bead portions  25  are arranged end to end to form, whereby four arc-shaped corner portions  250  are defined at four corners of the bezel  231  respectively. Each of the bead portions  25  protrudes towards the LCD panel  21  and contacts the fixing area  2113  of the first substrate  211 . Because of the bead portions  25 , a peripheral vertical gap is formed between the first substrate  211  and the top walls  2313 . A height of the gap is substantially the same as a thickness of the polarizer  215 . Peripheral edge portions of the polarizer  215  extend into the gap. Thereby, free end portions of the top walls  2313  cover the peripheral edge portions of the polarizer  215  with little pressure. 
     Also referring to  FIG. 3 , this is an enlarged view of a circled portion III of  FIG. 2 . The bead portion  25  includes a flat bottom  253  contacting the fixing area  2113  of the first substrate  21 . With the flat bottom  253 , the bead portion  25  disperses elastic pressure of the corresponding top wall  2313  of the bezel  23  over a large area. Thereby, the LCD panel  21  is tightly fixed in position with little or no risk of being damaged by excessive pressure exerted by the bead portions  25 . 
     With the above-described configuration, the top walls  2313  of the bezel  231  cover the peripheral edge portions of the polarizer  215 . Therefore, light leakage and associated light defects such as bright lines are effectively eliminated. In addition, because of the vertical gap between the first substrate  211  and the top walls  2313 , the polarizer  215  sustains little pressure from the bezel  231  and is effectively prevented from being distorted or damaged. Therefore the risk of the polarizer  215  producing mottling is substantially reduced or even eliminated. 
     Furthermore, the bead portion  25  (illustrated in  FIGS. 2 and 3 ) enlarges a gap L 4  between the corresponding top wall  2313  of the bezel  231  and the driver ICs  217  on the second substrate  213 . The gap L 4  provides a buffering space for protecting the driver ICs  217  from unwanted contact by the top wall  2313 . That is, the driver ICs  217  are prevented from being crushed by the top wall  2313 . 
     Moreover, the bead portions  25  enhance a mechanical strength of the top walls  2313  and the bezel  231 , which contributes to the overall mechanical strength of the housing assembly  23 . The corner portions  250  disperse pressure exerted by the top walls  2313  at the four corners of the bezel  231 . This facilitates preventing the corners of the LCD panel  21  from being crushed. Still further, the bead portions  25  can be conveniently made by a pressing or stamping process during manufacture of the bezel  231 . 
     Referring to  FIG. 4 , a schematic, top plan view of an LCD device  3  according to a second embodiment of the present invention is shown. The LCD device  3  has a similar structure to that of the LCD device  2 . However, each of top walls  3313  of a bezel  331  has two separate U-shaped bead portions  35  that are parallel to each other. The bead portions  35  at the four top walls  3313  are arranged end to end so as to form two substantially rectangular closed loops, with one of the loops being slightly larger than the other. 
     Also referring to  FIG. 5 , this is a cross-sectional view taken along line V-V of  FIG. 4 . Each of the bead portions  35  has a flat bottom  353 . The two flat bottoms  353  tightly press on a peripheral fixing area  3113  of the first substrate  311 . 
     With the two bead portions  35 , the bezel  331  has a large contact area with the peripheral fixing area  3113  of the first substrate  311 . Compared with the above-described first substrate  211  of the LCD device  2 , the first substrate  311  sustains less pressure intensity. Thus the LCD device  3  is very effectively prevented from being distorted or damaged by excessive pressure exerted by the top walls  3313  of the bezel  331 . Furthermore, the two bead portions  35  enhance the mechanical strength of the bezel  331 , which contributes to the overall mechanical strength of the LCD device  3 . 
     Referring to  FIG. 6 , a schematic, top plan view of an LCD device  4  according to a third embodiment of the present invention is shown. The LCD device  4  has a similar structure to that of the LCD device  3 . However, two separate, parallel bead portions  45  at each of top walls  4313  are separated from each of the adjacent bead portions  45  at each of the two corresponding adjacent top walls  4313 . With this configuration, pressure at four corners of the LCD panel  41  is reduced. Thereby, the risk of crushing of the corners of the LCD panel  41  can be significantly reduced or even eliminated. 
     Referring to  FIG. 7 , a schematic, top plan view of an LCD device  5  according to a fourth embodiment of the present invention is shown. The LCD device  5  has a similar structure to that of the LCD device  4 . However, each of only two opposite top walls  5313  of a bezel  531  has two separate, parallel bead portions  55  thereat. In the illustrated embodiment, the bead portions  55  are located at two opposite short top walls  5313 . In an alternative embodiment, the bead portions  55  can be located at two opposite long top walls  5313 . In further alternative embodiments, one or more bead portion  55  can be arranged at one more of the top walls  5313 , as required. 
     It is to be further understood that even though numerous characteristics and advantages of the present embodiments have been set out in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.