Patent Publication Number: US-2010128490-A1

Title: Light guide plate structure

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No(s). 097215337 filed in Taiwan, R.O.C. on Aug. 26, 2008, the entire contents of which are hereby incorporated by reference. 
     FIELD OF THE INVENTION 
     The present invention relates to a light guide plate structure, and more particularly to a light guide plate having reflecting sections provided on at least one face thereof by cutting the face to form a plurality of grooves at predetermined positions, so that the produced light guide plate has good flatness without the risk of deformation and provides uniform brightness when being used. 
     BACKGROUND OF THE INVENTION 
     Generally, a conventional light guide plate structure includes a light guide plate  41  and a plurality of reflecting sections  42  provided on the light guide plate  41 , as shown in  FIG. 1 . The reflecting sections  42  are formed on the light guide plate  41  by way of hot pressing or injection molding. Light beams from one or more light emitting units entering the light guide plate  41  via one side thereof are refracted at the reflecting sections  42  to thereby achieve the light guiding effect. 
     While the reflecting sections  42  provided on the light guide plate  41  refract the light beams to achieve the light guiding effect, the light guide plate  41  tends to deform and warp as shown in  FIG. 2 . This is because stress concentration occurs at and around the reflecting sections  42  when they are formed on the light guide plate  41  by hot pressing or injection molding. Therefore, the conventional light guide plate  41  can not meet the required flatness. The deformed or warped light guide plate  41  can not be easily and precisely assembled to a related electronic element, and would cause deviation in light refraction to result in non-uniform brightness when being used. 
     SUMMARY OF THE INVENTION 
     It is therefore a primary object of the present invention to provide a light guide plate structure with good flatness that can be precisely assembled to an electronic element to provide uniform brightness. 
     To achieve the above and other objects, the light guide plate structure according to a preferred embodiment of the present invention includes a light guide plate made of a light-transmitting material, and reflecting sections provided on at least one face of the light guide plate by cutting the face of the light guide plate to form a plurality of grooves at predetermined positions. 
     By cutting the face of the light guide plate to form the reflecting sections, the light guide plate structure can be more easily manufactured to ensure good flatness without the risk of deformation and accordingly ensures increased good yield thereof. The light guide plate structure with good flatness allows precise assembling of the light guide plate to a related electronic element and provides uniform brightness when being used. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein 
         FIG. 1  is a perspective view of a conventional light guide plate structure; 
         FIG. 2  is a side view of the conventional light guide plate structure of  FIG. 1 ; 
         FIG. 3  is a side view of a light guide plate structure according to a first embodiment of the present invention; 
         FIG. 4  is a side view of the light guide plate structure of  FIG. 3  in use; 
         FIG. 5  is a top view of the light guide plate structure of  FIG. 3  in use; 
         FIG. 6  is a side view of a light guide plate structure according to a second embodiment of the present invention; 
         FIG. 7  is a side view of the light guide plate structure of  FIG. 6  in use; 
         FIG. 8  is a top view of the light guide plate structure of  FIG. 6  in use; 
         FIG. 9  is a side view of a light guide plate structure according to a third embodiment of the present invention; 
         FIG. 10  is a side view of the light guide plate structure of  FIG. 9  in use; 
         FIG. 11  is a top view of the light guide plate structure of  FIG. 9  in use; 
         FIG. 12  is a side view of a light guide plate structure according to a fourth embodiment of the present invention; 
         FIG. 13  is a side view of a light guide plate structure according to a fifth embodiment of the present invention; 
         FIG. 14  is a side view of a light guide plate structure according to a sixth embodiment of the present invention; 
         FIG. 15  is a top view of a light guide plate structure according to a seventh embodiment of the present invention in use; 
         FIG. 16  is a sectional view taken along line A-A of  FIG. 15 ; and 
         FIG. 17  is a sectional view taken along line B-B of  FIG. 15 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Please refer to  FIG. 3  that is a side view of a light guide plate structure according to a first embodiment of the present invention; and to  FIGS. 4 and 5  that are side view and top view, respectively, of the light guide plate structure of  FIG. 3  in use. As shown, the light guide plate structure according to the first embodiment of the present invention includes a light guide plate  11  and a plurality of reflecting sections  12  provided on the light guide plate  11 . 
     The light guide plate  11  is made of a light transmitting material. 
     In the illustrated first embodiment, the reflecting sections  12  are provided on one face of the light guide plate  11  by cutting the face with a cutter  21  mounted on a cutting machine  20 , so as to form a plurality of V-shaped, U-shaped, or rectangular-shaped grooves at predetermined positions. In the illustrated embodiments of the present invention, the reflecting sections  12  each are a V-shaped groove. In this manner, the light guide plate  11  can be easily manufactured to show good flatness without the risk of deformation. Thus, the light guide plate structure of the present invention can be produced with increased good yield. In the first embodiment, the reflecting sections  12  are formed on one face of the light guide plate  11  at irregular intervals while having the same depth. And, the reflecting sections  12  can longitudinally or transversely extend or form a specific pattern on the face of the light guide plate  11 . 
     The light guide plate structure of the present invention can be associated with related electronic elements to serve as a light guide plate for, for example, keys on different electronic devices, a key board of an electronic produce, a backlight module, an instrument panel, a touch panel, or for a liquid crystal display (LCD). One or more light emitting units  30  as light sources can be correspondingly arranged to at least one side of the light guide plate  11 , so that light beams from the light emitting unit  30  enter the light guide plate  11  via the side thereof. The incident light beams are refracted at the reflecting sections  12  and finally exit the light guide plate  11  via another face thereof. With the good flatness thereof, the light guide plate  11  according to the present invention can be precisely assembled to a required electronic element, allowing the incident light beams to be refracted at the reflecting sections  12  to provide uniform brightness. Of course, according to actual need in use, the light emitting units  30  can be separately arranged adjacent to a top, a bottom, a left side, a right side, a front side, a rear side, and/or a central portion of the light guide plate  11 , so that the light guide plate structure of the present invention can always meet the requirements in different practical applications. 
       FIG. 6  is a side view of a light guide plate structure according to a second embodiment of the present invention; and  FIGS. 7 and 8  are side view and top view, respectively, of the light guide plate structure of  FIG. 6  in use. As shown, the light guide plate structure according to the second embodiment of the present invention includes a light guide plate  11  similar to that in the first embodiment, and is provided on one face thereof with a plurality of reflecting sections  12   a.  The reflecting sections  12   a  are formed on the face of the light guide plate  11  at regular intervals but have different depths, in order to meet required refracting paths for the light beams from the light sources. Therefore, the light guide plate structure according to the second embodiment of the present invention can also be easily and precisely manufactured without the risk of deformation. Meanwhile, when the light beams from the light emitting units  30  enter the light guide plate  11 , a unique refraction effect can be achieved via the reflecting sections  12   a,  allowing the light guide plate structure of the present invention to always meet the requirements in different practical applications. 
       FIG. 9  is a side view of a light guide plate structure according to a third embodiment of the present invention; and  FIGS. 10 and 11  are side view and top view, respectively, of the light guide plate structure of  FIG. 9  in use. As shown, the light guide plate structure according to the third embodiment of the present invention includes a light guide plate  11  similar to that in the first and the second embodiment, and is provided on one face thereof with a plurality of reflecting sections  12   b.  The reflecting sections  12   b  are formed on the face of the light guide plate  11  at irregular intervals and have different depths, in order to meet required refracting paths for the light beams from the light sources. Therefore, the light guide plate structure according to the third embodiment of the present invention can also be easily and precisely manufactured without the risk of deformation. Meanwhile, when the light beams from the light emitting units  30  enter the light guide plate  11 , a unique refraction effect can be achieve via the reflecting sections  12   b,  allowing the light guide plate structure of the present invention to always meet the requirements in different practical applications. 
       FIGS. 12 ,  13  and  14  are side views of light guide plate structures according to a fourth, a fifth, and a sixth embodiment of the present invention, respectively. In  FIG. 12 , the light guide plate structure according to the fourth embodiment of the present invention includes a light guide plate  11   a  being provided on two opposite faces with a plurality of reflecting sections  12 , and the reflecting sections  12  are formed on the faces of the light guide plate  11   a  at irregular intervals but have the same depth. In  FIG. 13 , the light guide plate structure according to the fifth embodiment of the present invention includes a light guide plate  11   b  being provided on two opposite faces with a plurality of reflecting sections  12   a,  and the reflecting sections  12   a  are formed on the faces of the light guide plate  11   b  at regular intervals but have different depths. In  FIG. 14 , the light guide plate structure according to the sixth embodiment of the present invention includes a light guide plate  11   c  being provided on two opposite faces with a plurality of reflecting sections  12   b,  and the reflecting sections  12   b  are formed on the faces of the light guide plate  11   c  at irregular intervals and have different depths. The light guide plates  11   a,    11   b  and  11   c  having differently formed reflecting sections  12 ,  12   b,    12   c,  respectively, can be used on different electronic products to achieve unique refraction effects, allowing the light guide plate structure of the present invention to always meet the requirements in different practical applications. 
       FIG. 15  is a top view of a light guide plate structure according to a seventh embodiment of the present invention in use, and  FIGS. 16 and 17  are sectional views taken along lines A-A and B-B of  FIG. 15 , respectively. As shown, the light guide plate structure according to the seventh embodiment includes a light guide plate  11   d,  and a plurality of reflecting sections  12   c  provided on at least one face of the light guide plate  11   d.  It is noted the reflecting sections  12   c  are selectively provided therein with at least one sunken area  121   c  of the same depth or different depths. Light emitting units  30  are arranged to at least one side of the light guide plate  11   d,  so that light beams emitted from the light emitting units  30  enter the light guide plate  11   d  and are differently refracted at the reflecting sections  12   c  and the sunken areas  121   c  in the reflecting sections  12   c,  allowing the light guide plate structure of the present invention to show changeful light refracting effects to always meet the requirements in different practical applications. 
     With the reflecting sections formed on the light guide plate by cutting, the light guide plate structure according to the present invention can be more easily manufactured at increased good yield to have good flatness without being easily subject to deformation. Meanwhile, the manufactured light guide plate can be easily and precisely assembled to a related electronic product and provide uniform brightness when being used. Therefore, the light guide plate structure of the present invention is novel and improved to effectively overcome the drawbacks in the conventional light guide plate structure, and is practical for industrial applications. 
     The present invention has been described with some preferred embodiments thereof and it is understood that many changes and modifications in the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.