Patent Publication Number: US-2010110723-A1

Title: Billboard utilizing backlight illumination

Description:
BACKGROUND 
     1. Technical Field 
     The present invention generally relates to billboards and, particularly, to a billboard utilizing backlight illumination, and a fabrication method thereof. 
     2. Discussion of Related Art 
     Conventional billboards generally include a light transmissive canvas on which patterns are printed and a backlight module for illuminating the light transmissive canvas. Light from the backlight module, however, is partly absorbed when passing through the light transmissive canvas. As such, light utilization efficiency of the billboards is low. 
     Therefore, what is needed is a billboard capable of overcoming the described shortcomings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present billboard can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present billboard. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views, wherein: 
         FIG. 1  is a schematic side view of a billboard, according to a first exemplary embodiment. 
         FIG. 2  is a schematic view of a display board of the billboard illustrated in  FIG. 1 . 
         FIG. 3  is a schematic view of a reflect board of the billboard illustrated in  FIG. 1 . 
         FIG. 4  is a schematic view of a reflect board according to a variation of the first embodiment. 
         FIG. 5  is a schematic view of a reflect board according to another variation of the first embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made to the drawing to describe the embodiments of the present billboard, in detail. 
     Referring to  FIG. 1  and  FIG. 2 , a billboard  10 , according to a first exemplary embodiment, is provided. The billboard  10  includes a frame  11 , a light emitting diode (LED) light source  12 , a display board  13  and a reflect board  14 . 
     The frame  11  is configured for supporting and fixing the LED light source  12 , the display board  13  and the reflect board  14 . The frame can be made of metal or plastic. In an exemplary embodiment, the frame  11  is made of metal. 
     The LED light source  12  is fixed on the frame  11  and configured for emitting lights. In an exemplary embodiment, a thermal interface material  120  is sandwiched between the LED light source  12  and the frame  11 . The thermal interface material  120  is configured for transferring heat from the LED light source  12  to the frame  11 , thereby assisting heat dissipation of the LED light source  12 . The thermal interface material  120  can be thermal grease, thermal paste or a thermal tape. 
     The display board  13  is fixed on the frame  11  and at one side of the LED light source  12 . The display board  13  includes a light incident surface  130 , a light emitting surface  132  and at least one through hole  134 . The light emitting surface  132  is opposite to the light incident surface  130 . The at least one through hole  134  extends through the display board  13  and communicates to the light incident surface  130  and the light emitting surface  132 . The at least one through hole  134  forms a predetermined logo, for example “FITI” as illustrated in  FIG. 2 . 
     The reflect board  14  is fixed on the frame  11  and at a side of the LED light source  12  opposite to the display board  13 . The reflect board  14  includes a light reflecting surface  140  facing towards the light incident surface  130  of the display board  13 . The reflect board  14  can be made of metal or plastic. The light reflecting surface  140  has metallic colors or white color. On the condition that part of the lights emitted from the LED source  12  incidents onto the light reflecting surface  140 , the light reflecting surface  140  reflects part of lights towards the light incident surface  130  of the display board  13 . Thereby, the light use efficiency is improved. 
     The light reflecting surface  140  can also have micro structure formed thereon, thereby randomly changing directions of the lights reflected by the light reflecting surface  140  and improving light uniformity thereof. In an exemplary embodiment, referring to  FIG. 3 , the light reflecting surface  140  has a plurality of round dots  142  formed thereon. The sizes of the dots  142  decrease in directions from a middle to opposite sides of the light reflecting surface  140 . Alternatively, the dots  142  can also be quadrate. It is to be said that, the light reflecting surface  140  can also have V-shaped grooves (as illustrated in  FIG. 4 ), pyramidal protrusions (as illustrated in  FIG. 5 ) or conical protrusions formed thereon instead. 
     In summary, the reflect board  14  and the LED source  12  cooperatively act as a backlight module for illuminating the display board  13 . With the display board  13  having at least one through hole  134  formed there through, lights passing through the through hole  134  is not absorbed by the display board  13 . As such, light utilization efficiency of the billboard  10  is improved. 
     Finally, it is to be understood that the above-described embodiments are intended to illustrate rather than limit the invention. Variations may be made to the embodiments without departing from the spirit of the invention as claimed. The above-described embodiment illustrates the scope of the invention but do not restrict the scope of the invention.