Patent Publication Number: US-10332701-B2

Title: Luminous keyboard

Description:
FIELD OF THE INVENTION 
     The present invention relates to a keyboard, and particularly, to a luminous keyboard. 
     BACKGROUND OF THE INVENTION 
     In modern society, use of electronic products has become an indispensable part in life, and almost everything, such as food, clothing, living, transport, education, and entertainment, is related to the electronic products. Generally, a consumer electronic product is provided with a keyboard. To increase the practicability of the keyboard, a backlight module is usually disposed inside the keyboard, and the backlight module can project generated light rays to key caps of the keyboard, to enable a user to operate the keyboard in a dimly lit environment. On the other hand, the backlight module can also be used to implement a keyboard prompting function. 
     In existing keyboard backlight technologies, a layer of a light guide plate structure may be disposed below a support plate of a keyboard, and corresponding light transmitting holes are disposed at positions of keys. In this way, light rays in the light guide plate may be obtained through the light transmitting holes and further projected to key caps of the keyboard, so that the keyboard produces an obvious highlight display effect. Alternatively, one or more light emitting components may be disposed in a particular area below a keyboard, and the light emitting component directly projects generated light rays to key caps of the keyboard. In the conventional technology, light emitting components are mainly light emitting diodes (LEDs). Because most of light rays emitted from an LED are concentrated around an optical axis, the LED is usually considered to be a point light source. However, when an LED is at a short distance from a key cap, because light rays emitted from the LED are excessively concentrated, the light rays emitted from the LED cannot be effectively spread to the entire key cap. Consequently, a phenomenon of the uneven brightness occurs on a surface of the key cap. Further, if light rays emitted from an LED are excessively strong, a notable bright spot may be generated on a surface of a key cap, making it difficult for a user to recognize a character symbol of the key cap, leading to inconvenience in use. 
     Therefore, how to improve the brightness of light emission, the irradiation angle, and the evenness of light emergence of a light emitting module is a technical problem to be resolved by the present invention. 
     SUMMARY OF THE INVENTION 
     A main objective of the present invention is to provide a luminous keyboard, including a light emitting module capable of adjusting an irradiation range according to character symbols of different key caps, so as to improve recognizability of a character symbol of each key cap. 
     To achieve the foregoing objective, the present invention provides a luminous keyboard, including: 
     at least one key cap; 
     a support plate; 
     a support component, connected to the key cap and the support plate and capable of guiding the key cap to vertically move relative to the support plate; 
     a thin film circuit board, disposed on the support plate; 
     at least one light emitting component, configured to emit a light ray to the at least one key cap; and 
     a shield, covering the at least one light emitting component, where 
     there is a gap between the shield and the at least one light emitting component, and the shield is provided with a diffraction grating at a position where the light ray passes through the shield. 
     In the foregoing preferred implementation, the shield includes: a light emergence part, a sidewall part, a fixing part, and an accommodation space. 
     In the foregoing preferred implementation, the light emergence part includes a first surface and a second surface opposite to the first surface. 
     In the foregoing preferred implementation, an ink layer is formed on the first surface or the second surface, and the ink layer includes a plurality of slits to form the diffraction grating, and the diffraction grating is configured to adjust an irradiation range of the light ray. 
     In the foregoing preferred implementation, the light emergence part includes a plurality of slits, the slits run through the first surface and the second surface to form the diffraction grating, and the diffraction grating is configured to adjust an irradiation range of the light ray. 
     In the foregoing preferred implementation, the fixing part is configured to fix the shield to the thin film circuit board. 
     In the foregoing preferred implementation, the accommodation space is configured to accommodate the light emitting component, and a volume of the accommodation space is larger than a volume of the light emitting component, so that the gap is formed. 
     In the foregoing preferred implementation, the light emitting component is an LED chip or an electro luminescence (EL) chip. 
     In the foregoing preferred implementation, the shield is made of polyethylene terephthalate (PET) or a reflector material. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a top view of a luminous keyboard according to the present invention; 
         FIG. 2  is a sectional view of a structure of a light emitting module; 
         FIG. 3A  is an enlarged view of a first embodiment of a slit structure in an area A in  FIG. 2 ; 
         FIG. 3B  is an enlarged view of a second embodiment of a slit structure in an area A in  FIG. 2 ; 
         FIG. 4A  and  FIG. 4B  are schematic diagrams of irradiation range adjustment of a light emitting module; and 
         FIG. 5A  and  FIG. 5B  are schematic diagrams of irradiation range adjustment of a light emitting module. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The advantages and features of the present invention and the method for implementing the same are more readily understood with reference to the following more detailed description of exemplary embodiments and accompanying drawings. However, the present invention may be implemented in different forms, and should not be understood as being limited to the embodiments described herein. Rather, for persons of ordinary skill in the art, these embodiments are provided so that this disclosure will be more thorough and comprehensive, and will fully convey the concept of the present invention. 
     First, referring to  FIG. 1 ,  FIG. 1  is a top view of a luminous keyboard according to the present invention. In  FIG. 1 , a luminous keyboard  10  includes a key cap  11 , a support component  12 , a support plate  13 , a thin film circuit board  14 , an elastic component  15 , and a light emitting module  16 . The elastic component  15  is disposed below a key cap  11 . The support component  12  is a scissors foot structure, is configured to connect the key cap  11  and the support plate  13 , and surrounds the elastic component  15 . The light emitting module  16  is disposed above the thin film circuit board  14  and is configured to project a light ray to the key cap  11  or a character symbol area  111  on a surface of the key cap  11 , so that the surface or the character symbol area  111  of the key cap  11  produces a light emitting visual effect. 
     Still referring to  FIG. 1 , the support plate  13  includes joint parts  131  and  132 , the thin film circuit board  14  is disposed above the support plate  13 , and the joint parts  131  and  132  of the support plate  13  may be disposed in openings (not shown) of the thin film circuit board  14  in a penetrating manner When the keyboard is assembled, one end of the support component  12  may be pivotally connected to the key cap  11  (not shown), the other end of the support component  12  is pivotally connected to the joint parts  131  and  132  of the support plate  13 . In this way, the support component  12  is rotatably connected between the key cap  11  and the support plate  13 , so as to actuate and guide the key cap  11  to perform descending and ascending actions relative to the support plate  13 . Moreover, when the key cap  11  is pressed and descends, the elastic component  15  disposed below the key cap  11  deforms because of being extruded by the key cap  11 , and at this moment, a key switch (not shown) on the thin film circuit board  14  is triggered by the elastic component  15  and further outputs a corresponding key signal. Further, when the key cap  11  is not pressed, the elastic component  15  provides an upward elastic returning force for the key cap  11 , so as to push the key cap  11  upward and return to its original position. The elastic component  15  made be made of rubber, silica gel, or a metal dome. On the other hand, although the present invention provides only the implementation that the support component  12  is a scissors foot structure, during actual application, the support component  12  may alternatively be replaced with another support component having a similar function such as a V-type structure, an A-type structure, or two parallel link rod structures, and is not limited to the implementations provided in the present invention. 
     Referring to  FIG. 2 ,  FIG. 2  is a sectional view of a structure of a light emitting module. In  FIG. 2 , the light emitting module  16  includes a light emitting component  161  and a shield  162 . The light emitting component  161  may be an LED chip or an EL chip, and can emit a light ray L by means of application of a current. The shield  162  includes: a light emergence part  1621 , a sidewall part  1622 , a fixing part  1623 , and an accommodation space C constituted by the light emergence part  1621  and the sidewall part  1622 . 
     The shield  162  is configured to cover the light emitting component  161  and accommodate the light emitting component  161  by means of the accommodation space C. Further, the fixing part  1623  may be configured to fix the shield  162  onto the thin film circuit board  14 . In addition, because a volume of the accommodation space C is larger than a volume of the light emitting component  161 , a gap may be formed between the shield  162  and the light emitting component  161 . An area of the light emergence part  1621  is larger than an area of the light emitting component  161 , and the light emergence part  1621  includes a first surface  16211 , a second surface  16212  opposite to the first surface  16211 , and a plurality of slits S, where the slits S may be line-type slits or dot-shaped slits. Because the area of the light emergence part  1621  is larger than the area of the light emitting component  161 , and because there is a gap between the shield  162  and the light emitting component  161 , the formed gap can enable the second surface  16212  serving as an incident plane to completely receive the light ray L emitted from the light emitting component  161  when the light emitting component  161  emits a light ray L because of application of a current, the brightness of light emission of the light emitting module  16  can be effectively improved. On the other hand, the light emergence part  1621  including the plurality of slits S can be used as a diffraction grating. When the light ray L passes through the slits S of the light emergence part  1621 , the light ray L begins to expand to two sides because of a diffraction effect. In this way, the light emitting module  16  can adjust the irradiation angle and improve the evenness of light emergence by means of the slits S, and an irradiation range of the light emitting module  16  is directed toward a position of the character symbol area  111  (as shown in  FIG. 1 ). 
     Still referring to  FIG. 3A ,  FIG. 3A  is an enlarged view of a first embodiment of a slit structure in an area A in  FIG. 2 . In this embodiment, the shield  162  is a transparent cover body, and is made of PET. In addition, because the shield  162  is a transparent cover body to be passed through by the light ray L, a tone of light emitted from the light emitting module  16  can be adjusted by adjusting a color of the shield  162 . Subsequently, light-proof ink is coated on the first surface  16211  of the light emergence part  1621  by means of a spray coating or printing process, to form an ink layer  163  including a plurality of slits S. The ink layer  163  including the plurality of slits S can be used as a diffraction grating. When the light ray L passes through the slits S of the ink layer  163 , a diffraction effect occurs and the light ray L begins to expand to two sides. In this way, the irradiation angle of the light emitting module  16  can be adjusted by means of the slits S formed on the ink layer  163 , and the evenness of light emergence of the light emitting module  16  is improved at the same time. Smaller widths d of the formed slits S indicate a greater expansion angle θ of the light ray after the light ray L passes through the formed slits S. Although the present invention provides only the implementation that the ink layer  163  including the plurality of slits S is formed on the first surface  16211 , during actual application, an ink layer including a plurality of slits may alternatively be formed on the second surface  16212  or an inner or outer surface of the sidewall part  1622 , and is not limited to the implementations provided in the present invention. 
     Still referring to  FIG. 3B ,  FIG. 3B  is an enlarged view of a second embodiment of a slit structure in an area A in  FIG. 2 . In this embodiment, the shield  162  is an opaque cover body, and is made of a reflector material. Subsequently, a plurality of slits S penetrating through the first surface  16211  and the second surface  16212  are formed in an area of the light emergence part  1621  by means of a punching process, and the light emergence part  1621  including the plurality of slits S can be used as a diffraction grating. When the light ray L passes through the slits S of the light emergence part  1621 , a diffraction effect occurs and the light ray L begins to expand to two sides. In this way, the irradiation angle of the light emitting module  16  can be adjusted by means of the slits S penetrating through the first surface  16211  and the second surface  16212 , and the evenness of light emergence of the light emitting module  16  is improved at the same time. Smaller widths d of the formed slits S indicate a greater expansion angle θ of the light ray after the light ray L passes through the formed slits S. Although the present invention provides only the implementation that the plurality of slits S penetrating through the first surface  16211  and the second surface  16212  is formed on the first surface  16211 , during actual application, the plurality of slits S may alternatively be formed on the sidewall part  1622 , and is not limited to the implementations provided in the present invention. On the other hand, although the present invention provides only the implementation that a single shield  162  is disposed on a single light emitting component  161 , during actual application, a plurality of shield structures configured to cover a light emitting component may alternatively be formed in a Mylar sheet (not shown) on the thin film circuit board  14 . In addition, a width of a slit of each shield may be adjusted according to a position of a character symbol area of each key cap, the irradiation angle of the light emitting module is adjusted by adjusting the width of the slit, to direct an irradiation range of the light emitting module toward the position of the character symbol area, so that the brightness and the evenness of light emission of the character symbol area of each key cap can be effectively improved. 
     Referring to  FIG. 4A ,  FIG. 4B ,  FIG. 5A , and  FIG. 5B  together,  FIG. 4A ,  FIG. 4B ,  FIG. 5A , and  FIG. 5B  are schematic diagrams of irradiation range adjustment of a light emitting module.  FIG. 4A  is a top view of the key cap  11 , where the character symbol area  111  is disposed at a position close to the center on the surface of the key cap  11 , and the character symbol area  111  is made of a transparent material, so that a light ray emitted from the light emitting module  16  can pass through the surface of the character symbol area  111 , to enable a user to recognize a character or a symbol on the key cap  11  such as a symbol “@” displayed in the character symbol area  111 . Subsequently, refer to  FIG. 4B . In  FIG. 4B , the light emitting module  16  is disposed below the key cap  11 . Because the character symbol area  111  is disposed at a position close to the center on the surface of the key cap  11 , a light emitting module  16  with slits S having relatively large widths can be used, and an irradiation range of the light emitting module  16  is maintained to be toward the area above, so that the character symbol area  111  can receive irradiation of more light rays, thereby effectively improving the brightness of light emission of the character symbol area  111 . On the other hand, after the light ray L passes the slits S and produces a diffraction effect, the light ray L generated by the light emitting component  161  (as shown in  FIG. 2 ) is changed from a point light source form to a surface light source form, so that the evenness of light emission of the character symbol area  111  of the key cap  11  is effectively improved. 
     Still referring to  FIG. 5A  and  FIG. 5B ,  FIG. 5A  is a top view of the key cap  11 , where the character symbol area  111  is disposed at a center-left position on the surface of the key cap  11 , and the character symbol area  111  is made of a transparent material, so that a light ray emitted from the light emitting module  16  can pass through the surface of the character symbol area  111 , to enable a user to recognize a character or a symbol on the key cap  11  such as a symbol “@” displayed in the character symbol area  111 . Subsequently, referring to  FIG. 5B , in  FIG. 5B , the light emitting module  16  is disposed below the key cap  11 . Because the character symbol area  111  is disposed at a center-left position on the surface of the key cap  11 , a light emitting module  16  with slits S having relatively small widths can be used, and an irradiation range of the light emitting module  16  is maintained to be directed toward the area on the top left of the light emitting module  16 , so that the character symbol area  111  at the center-left position on the key cap  11  can receive irradiation of more light rays, thereby effectively improving the brightness of light emission of the character symbol area  111 . On the other hand, after the light ray L passes the slits S and produces a diffraction effect, the light ray L generated by the light emitting component  161  (as shown in  FIG. 2 ) is changed from a point light source form to a surface light source form, so that the evenness of light emission of the character symbol area  111  of the key cap  11  is effectively improved. 
     Compared with the conventional technology, the luminous keyboard provided in the present invention includes a light emitting component that can improve the brightness of light emission of a light emitting module by using a configured shield. On the other hand, the irradiation angle of a light ray can be adjusted by means of slits on the shield, to direct an irradiation range of the light emitting module toward a position of a character symbol area of a key cap, so that the character symbol area can receive irradiation of more light rays, thereby effectively improving the brightness of light emission of the character symbol area. In addition, by means of the slits on the shield, light rays emitted from the light emitting component can be changed from a point light source form to a surface light source form, and the evenness of light emission of the light emitting module is improved at the same time, so that phenomena that the brightness of a surface of a key cap of a keyboard is even or bright spots are excessively concentrated can be effectively reduced. Therefore, the present invention is essentially of high industrial value. 
     Any modification to the present invention readily figured out by a person skilled in the art shall fall within the protection scope of the appended claims.