Abstract:
An exemplary keyboard is provided. The keyboard includes a light pervious base plate, a plurality of input keys, and at least one light source. The light pervious base plate has a top surface. The plurality of input keys are disposed on the light pervious base plate with bottom sides of the input keys facing the top surface of the light pervious base plate. The at least one light source is encapsulated in the light pervious base plate and optically coupled to the light pervious panel.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present invention relates to keyboards, and particularly to a keyboard having a lighting system used in conjunction with a computer system. 
         [0003]    2. Description of Related Art 
         [0004]    A keyboard is commonly used in conjunction with a computer as an input device. Keyboards usually have a plurality of keycaps wherein alphanumeric symbols (or symbols in foreign languages) are printed on the keycaps to help users select the desired input to the computer. Under normal condition, such as under a brightly lit environment, the users typically can clearly identify the symbols on the keycaps. However, in a dark environment or in a low ambient light condition, the symbols on the keycaps may not be clearly visible to the users. 
         [0005]    Therefore, a keyboard with a lighting system is desirable to overcome the above-described deficiencies. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    Many aspects of various preferred and exemplary embodiments 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 embodiments. Moreover, in the drawings, all the views are schematic, and like reference numerals designate corresponding parts throughout the several views. 
           [0007]      FIG. 1  is a schematic isometric view of an exemplary keyboard according to a first embodiment. 
           [0008]      FIG. 2  is a cross-sectional view taken along line II-II of  FIG. 1 . 
           [0009]      FIG. 3  is a cross-sectional view of an exemplary keyboard according to a second embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]    Embodiments will now be described in detail below, with reference to the drawings. 
         [0011]    Referring to  FIGS. 1 and 2 , a keyboard  10  in accordance with a first embodiment includes a light pervious panel  12  having a top surface  120 , a plurality of input keys  13  on the top surface  120 , and at least one of light sources  11  wrapped or encapsulated in the light pervious panel  12 . 
         [0012]    In the first embodiment, each of the input keys  13  has a top side with alphanumeric symbols printed thereon, and a bottom side facing away from the top side and having a plurality of first conductive tracks  170  (e.g., silver ink) printed thereon. The top surface  120  of the light pervious panel  12  also has a plurality of second conductive tracks  172  printed thereon. The second conductive tracks  172  are aligned with the first conductive tracks  170 . A support mechanism  16  (e.g., coil spring) is arranged between each of the input keys  13  and the top surface  120  of the light pervious panel  12  and configured for connecting the input keys  13  with the light pervious panel  12 . 
         [0013]    When the input key  13  is pressed, the coil spring  16  is depressed, and the first conductive tracks  170  press against the second conductive tracks  172  to form a complete circuit. When an input key  13  is pressed and the circuit is completed, a code is generated and sent to the computer either via a keyboard cable (not shown) or over a wireless connection. The input keys  13  of  FIG. 1  may be arranged in a variety of patterns. 
         [0014]    The input keys  13  are typically arranged in conventional patterns of alphanumeric and other symbols, as found with most personal computers, to guide the user in providing appropriate input via the keyboard  10 . 
         [0015]    To facilitate illumination of the keyboard  10 , and specifically input keys  13 , at least one part of each input key  13  comprises a light transfer portion to permit passage of light transmitting therethrough from the light pervious panel  12 . The light transfer portion can be the entire input key  13  or just the portions where the symbols are located. In one example, the input keys  13  are made out of a translucent material or a light pervious material. Transparent acrylonitrile butadiene styrene (ABS) plastic is an example of such material. In this embodiment, the light transfer portion defines the entire input key  13 . In another example, the outer surfaces of translucent input keys  13  are made out of an opaque material and the light transfer portion of this opaque material is etched so that it transmits light. The etched portion can be patterned to define the symbols on each of the strike surface. Another potential arrangement includes placement of opaque symbols in the input keys  13  which is formed of a translucent material to allow transmission of light around the symbols. 
         [0016]    The at least one of light sources  11  may includes a plurality of light emitting diodes (LEDs). The LEDs are commercially available in a variety of colors such as white, yellow, blue, and green. In the first embodiment, the plurality of light sources  11  is electrically mounted on a circuit board  14 . The circuit board  14  can be a print circuit board (PCB), a flexible PCB, a metal core PCB, a thin film PCB, etc. The circuit board  14  includes an electrical connector  140  coupled to a power source (not shown) for powering the light sources  11 , and a control circuit  142  for controlling the intensity of the light sources  11 . The power source may be a battery or the power source of keyboard  10 . A variety of methods, devices, and circuitry for controlling the intensity of the light sources  11  will readily be recognized by persons of ordinary skill in the art. 
         [0017]    The light pervious panel  12  can be made out of glass, plastic, or other suitable light pervious materials. In the first embodiment, the material of the light pervious panel  12  is selected from the group consisting of polymethyl methacrylate (PMMA), polycarbonate (PC), and silicon. The material of the light pervious panel  12  can further comprise a plurality of light diffusers  128  for diffusing light beams emitted from the light sources  11 , and a plurality of micro structures (not shown) can be defined in the top surface  120  of the light pervious panel for the same purpose. The material of the light pervious panel also can further comprise optical transition materials, such as phosphors, dyes. 
         [0018]    The light sources  11  are encapsulated or wrapped in the light pervious panel  12  by an injection molding process or a hot embossing process. As such, the light sources  11  are integral components of the light pervious panel  12  and optically coupled to the light pervious panel  12 . The injection molding process can help keep air bubbles from forming in the final part of the light pervious panel  12 , thereby enhancing efficiency of light transmission thereof. Furthermore, a reflect film  122  can be formed on outer surface of the light pervious panel  12  except for the top surface  120 . 
         [0019]    Referring to  FIG. 3 , a keyboard  30  in accordance with a second embodiment includes a light pervious keyboard membrane  330 , light pervious panel  32  having a top surface  320 , and at least one of light sources  31  wrapped or encapsulated in the light pervious panel  32 . 
         [0020]    In the second embodiment, the keyboard membrane  330  is made out of soft plastic, or other suitable material that is light pervious and flexible. The keyboard membrane  330  having a top surface  33 B with alphanumeric symbols (not shown) printed thereon, and a bottom surface  33 A facing away from the top surface  33 B and having a plurality of first conductive tracks  372  (e.g., silver ink) printed thereon. The keyboard membrane  330  is divided into a plurality of key portions  33  corresponding to alphanumeric symbols. 
         [0021]    A plurality of recesses  35  are defined in the top surface  320 . The recesses  35  are aligned with the first conductive tracks  372  printed on the keyboard membrane  330 . The bottom surface  350  of each recess  35  is printed with a plurality of second conductive tracks  370  (e.g., silver inks) thereon. Through the recesses  35 , the first conductive tracks  372  of the keyboard membrane  330  may contact the corresponding second conductive tracks  370  on the light pervious panel  32 , when the key portions  33  are pressed. 
         [0022]    The structures of the light pervious panel  32  and the light sources  31  are similar with that of the light pervious panel  12  and the light sources  11  in the first embodiment. The difference is that the circuit board  34  includes a solar cell battery  342  coupled thereto and encapsulated in the light pervious panel  32 . The solar cell battery  342  is configured for driving the light sources  31 . The keyboard membrane  330  can be integrally formed with the light pervious panel  32  as a single body. As such, the keyboard  30  can be fully immersed in water, making them popular in hospitals and laboratories, as they can be disinfected. 
         [0023]    It is to be understood, however, that even though numerous characteristics and advantages of various embodiments have been set forth in the foregoing description together with details of the structures and functions of the embodiments, the disclosure is illustrative only; and that 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.