Abstract:
The invention provides backlight module comprising a light guiding plate, a flexible substrate, and a light emitting unit. The flexible substrate has a first surface, and the light emitting unit is configured on the first surface. A paint area used for reflecting the light, emitted by the light emitting unit, to the light guiding plate is formed on the first surface near the light emitting unit. Accordingly, the light emitted into the light guiding plate could be prevented from being reflected by the flexible substrate directly and presenting the same color with the flexible substrate.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a backlight module and a keyboard comprising the same. Particularly, the invention relates to a backlight module which can completely display the color of the light emitted from a light emitting unit, and a keyboard comprising the same. 
         [0003]    2. Description of the Prior Art 
         [0004]    Generally speaking, a backlight module of a light-emitting keyboard includes a light guiding plate for guiding the light emitted from a light emitting element all over the light guiding plate and for reflecting the light to the operation surface of the keyboard. Accordingly, users can observe the light emitted from the light guiding plate and have a vision effect. 
         [0005]    Please refer to  FIG. 1 .  FIG. 1  is a schematic diagram illustrating a backlight module  1  of a light-emitting keyboard according to prior art. As shown in  FIG. 1 , the backlight module  1  comprises a light emitting element  10 , a flexible substrate  12  and a light guiding plate  14 . The light emitting element  10  is disposed on the flexible substrate  12  and is controlled by the flexible substrate  12 . The light emitted from the light emitting element  10  is irradiated to the light guiding plate  14  and is conducted in the light guiding plate  14 . The light guiding plate  14  further comprises a reflecting patch or a reflecting structure (not shown in  FIG. 1 ), disposed at the bottom of the light guiding plate  14 , for reflecting the light from the light guiding plate  14  to the keyboard, so that users can observe the light emitted from the light guiding plate and have a vision effect. 
         [0006]    However, because the color of the flexible substrate is different from that of the light emitted from the light emitting element (for example, light emitting diode) of the light-emitting keyboard, the flexible substrate can only reflect the light with the same color thereof to the light guiding plate. Therefore, the color of the light provided by the part of the light guiding plate near the light emitting element is easily be affected by the flexible substrate. For a designer&#39;s consideration, the light reflected by the flexible substrate to the light guiding plate will generate a bad influence for the vision effect of the light-emitting keyboard, especially that the larger keyboard needs more light emitting units, and then increases the degree of bad vision effect. Therefore, how to improve the influence of the flexible substrate to the light-emitting keyboard becomes one of the research points of the backlight module. 
       SUMMARY OF THE INVENTION 
       [0007]    Accordingly, an aspect of the present invention is to provide a backlight module for solving aforementioned problem. 
         [0008]    According to an embodiment, the backlight module of the present invention comprises a light guiding plate, a flexible substrate and a light emitting unit. The flexible substrate has a first surface, and the light emitting unit is disposed on the first surface. A paint area is formed on the first surface near the light emitting unit for reflecting the light emitted from the light emitting unit to the light guiding plate. 
         [0009]    In the embodiment, the paint area is formed on the first surface near an outlet of the light emitting unit, so as to reflect the light emitted from the outlet of the light emitting unit to the light guiding plate. In practice, the paint area is formed of white paint or white ink. 
         [0010]    According to another embodiment, a keyboard of the invention includes a keyboard module and a backlight module, wherein the backlight module is disposed under the keyboard module as a light source to the keyboard module. The backlight module further includes a light guiding plate, a flexible substrate and a light emitting unit. The light guiding plate is disposed under the keyboard module, and the light guiding plate has a space. The flexible substrate has a first surface. The light emitting unit is disposed on the first surface. Moreover, the light emitting unit is also contained in the space. Particularly, a paint area is formed on the first surface near the light emitting unit for reflecting the light emitted from the light emitting unit to the light guiding plate. 
         [0011]    As mentioned above, the paint area is formed on the first surface near an outlet of the light emitting unit, so as to reflect the light emitted from the outlet of the light emitting unit to the light guiding plate. In practice, the paint area is formed of white paint or white ink. 
         [0012]    The objective of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment, which is illustrated in following figures and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE APPENDED DRAWINGS 
         [0013]      FIG. 1  is a schematic diagram illustrating a backlight module applied to a light-emitting keyboard according to prior art. 
           [0014]      FIG. 2  is a partial view of a backlight module according to an embodiment of the invention. 
           [0015]      FIG. 3  is a top view of a light emitting unit disposed on a flexible substrate according to another embodiment of the invention. 
           [0016]      FIG. 4  is a partial view of a backlight module according to another embodiment of the invention. 
           [0017]      FIG. 5  is a partial view of a keyboard according to an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    Please refer to  FIG. 2 .  FIG. 2  is a partial view of a backlight module  2  according to an embodiment of the invention. As shown in  FIG. 2 , the backlight module  2  of the invention includes a light guiding plate  20 , a flexible substrate  22  and a light emitting unit  24 . The light guiding plate  20  includes a space  200  for containing the light emitting unit  24 . The light emitting unit  24  is simultaneously disposed on the first surface  220  of the flexible substrate  22 . In practice, the backlight module  2  of the embodiment can be applied in a light-emitting keyboard as a light source. 
         [0019]    A part of the light emitted from the light emitting unit  24  injects into the light guiding plate  20  directly, and a part of the light injects on the first surface  220  of the flexible substrate  22 . In practice, the light emitting unit  24  can be, but not limited to, a light emitting diode. A paint area  222  is formed on the first surface  220  of the flexible substrate  22  near the light emitting unit  24 . Moreover, the paint area  222  reflects the light emitted from the light emitting unit  24  to the light guiding plate  20 . 
         [0020]    Please not that there is only a light emitting unit  24  illustrated in the backlight module  2  of  FIG. 2 . However, in practice, the number and the position of the light emitting unit  24  can be changed depends on the demand of a user or a designer. Additionally, in practice, the paint area  222  of this embodiment can be formed on the first surface  220  near each of the light emitting units  24  for reflecting the light emitted from the light emitting units  24  to the light guiding plate  20 . 
         [0021]    Please refer to  FIG. 3 .  FIG. 3  is a top view illustrating a light emitting unit  24  disposed on a flexible substrate  22  according to another embodiment of the invention. As shown in  FIG. 3 , both ends of the light emitting unit  24  are connected to the first surface  220  of the flexible substrate  22  via tabs  224 . The paint area  222  is formed on the first surface  220  near the light emitting unit  24 , especially near an outlet  240  of the light emitting unit  24 , so as to reflect the light emitted from the outlet  240  of the light emitting unit  24  to the light guiding plate  20 . Please note that the outlet  240  is disposed at one side of the light emitting unit  24  in the embodiment. However, in practice, the number and the position of the outlet  240  of the light emitting unit  24  can be changed depends on the demand of the user or the designer. 
         [0022]    In the embodiment, a white material, for example, white paint or white ink, is used to paint on the first surface  220  to form the paint area  222 . Because the paint area  222  is formed of said white material, the light emitted from the light emitting unit  24  can be completely reflected from the paint area  222  to the light guiding plate  20 , and the light injected into the light guiding plate  20  has the same color, i.e., the color of the light emitted from the light emitting unit  24 . 
         [0023]    In another embodiment, the paint area  222  of the invention can be formed of a material with the same color of the light emitted from the light emitting unit  24 . Accordingly, the color of the light reflected to the light guiding plate  20  will be the same as the color of the light emitted from the light emitting unit  24 . 
         [0024]    Please refer to  FIG. 4 .  FIG. 4  is a partial view of a backlight module  2  according to another embodiment of the invention. As shown in  FIG. 4 , the difference between this embodiment and the last one is that the backlight module  2  of this embodiment further includes a reflecting unit  26  disposed between the flexible substrate  22  and the light guiding plate  20 . 
         [0025]    In the embodiment, the reflecting unit  26  is a sheet, and the size of the sheet is substantially the same as the size of the light guiding plate  20 . When the light in the light guiding plate  20  is transmitted to the reflecting unit  26 , the reflecting unit  26  reflects the light back into the light guiding plate  20  to ensure the light continuously transmitted in the light guiding plate  20 . Additionally, in practice, the reflecting unit  26  can be suitably designed to have different functions. For example, a reflecting patch can be pasted on the reflecting unit  26 , so as to reflect the light in the light guiding plate  20  to another surface of the light guiding plate  20  to be a light source to the keyboard. 
         [0026]    Additionally, a hole (not shown in  FIG. 4 ) can be formed at the position on the reflecting unit  26  corresponding to the space  200 . The light emitting unit  24  passes through the hole to be contained in the space  200 . In practice, the number and the position of the hole correspond to the number and the position of the light emitting unit  24  to be disposed on the reflecting unit  26 . 
         [0027]    Please refer to  FIG. 5 .  FIG. 5  is a partial view of a keyboard  3  according to an embodiment of the invention. As shown in  FIG. 5 , the keyboard  3  includes a keyboard module  30  and a backlight module  32 , wherein the backlight module  32  is disposed under the keyboard module  30  to provide a light source to the keyboard module  30 . 
         [0028]    In the embodiment, the backlight module  32  further comprises a light guiding plate  320 , a flexible substrate  322  and a light emitting unit  324 . The light guiding plate  320  is disposed under the keyboard module  30 , wherein the light guiding plate  320  has a space  3200 . The light emitting unit  324  is disposed on a first surface  3220  of the flexible substrate  322 , and the light emitting unit  324  is contained in the space  3200 . 
         [0029]    A part of the light emitted from the light emitting unit  324  injects into the light guiding plate  320  directly, and a part of the light injects on the first surface  3220  of the flexible substrate  322 . In practice, the light emitting unit  324  can be, but not limited to, a light emitting diode. A paint area  3222  is formed on the first surface  3220  of the flexible substrate  322  near the light emitting unit  324 . Moreover, the paint area  3222  reflects the light emitted from the light emitting unit  324  to the light guiding plate  320 . 
         [0030]    In the embodiment, a white material, for example, white paint or white ink, is used to paint on the first surface  3220  to form the paint area  3222 . Because the paint area  3222  is formed of said white material, the light emitted from the light emitting unit  324  can be completely reflected from the paint area  3222  to the light guiding plate  320 , and the light injecting into the light guiding plate  320  has the same color, i.e., the color of the light emitted from the light emitting unit  324 . In practice, the paint area  3222  of the invention can be formed of a material with the same color of the light emitted from the light emitting unit  324 . Accordingly, the color of the light reflected to the light guiding plate  320  will be the same as the color of the light emitted from the light emitting unit  324 . 
         [0031]    As mentioned above, because the paint area  3222  covers the flexible substrate  322 , the light emitted from the light emitting unit  324  can be completely reflected by the paint area  3222  to the light guiding plate  320 . Practically, the color of the paint area  3222  can be white or the same color of the light emitted from the light emitting unit  324 . Accordingly, the color of the light reflected by the paint area  3222  is the same as the color of the light injected directly from the light emitting unit  324  to the light guiding plate  320 , so as to solve the problem in the prior art. 
         [0032]    According to another embodiment, the backlight module of the keyboard of the invention further includes a reflecting unit disposed between the light guiding plate and the flexible substrate. In the embodiment, the reflecting unit is a sheet and the size of the sheet is substantially the same as the size of the light guiding plate or the keyboard. When the light in the light guiding plate is transmitted to the reflecting unit, the reflecting unit reflects the light back into the light guiding plate to ensure the light continuously transmitted in the light guiding plate. Additionally, in practice, the reflecting unit can be suitably designed to have different functions. For example, a reflecting patch can be pasted on the reflecting unit, so as to reflect the light in the light guiding plate to another surface of the light guiding plate to be a light source to the keyboard. 
         [0033]    In the embodiment, a hole can be formed at the position on the reflecting unit corresponding to the space. The light emitting unit passes through the hole to be contained in the space. In practice, the number and the position of the hole correspond to the number and the position of the light emitting unit to be disposed on the reflecting unit. 
         [0034]    Compared to the prior art, a paint area is formed on the surface of the flexible substrate of the backlight module of the invention near the light emitting unit. The paint area reflects the light emitted from the light emitting unit to the light guiding plate to ensure the light continuously transmitted in the light guiding plate. The paint area is formed by painting a material on the surface of the flexible substrate, wherein the material is a white material, such as white paint or white ink, or the material has the same color as the light emitted from the light emitting unit. Therefore, the paint area can completely reflect the light emitted from the light emitting unit to the light guiding plate. The color of the light injected into the light guiding plate is the same as the color of the light emitted from the light emitting unit, so as to improve the disadvantage of the prior art. 
         [0035]    With the example and explanations above, the features and spirits of the invention will be hopefully well described. Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teaching of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.