Patent Abstract:
An electromagnetic shielding system including a circuit board, a display and a shield is described. The shield includes a face having an opening through which the display is visible. A wall portion extends from the face of the shield towards the circuit board. As a result, the display is substantially encapsulated between the circuit board, the shield and the wall portion.

Full Description:
BACKGROUND 
     1. Field of the Invention 
     The present invention generally relates to electromagnetic shielding of display systems and, more particularly, to the electromagnetic shielding of vacuum fluorescent display systems. 
     2. Description of the Know Technology 
     Display systems, such as vacuum fluorescent display systems, may be coupled to a circuit board. The display system is one of many components populating the circuit board. A vacuum fluorescent display (VFD) is a type of display used primarily on consumer electronic equipment such as head unit for automobile entertainment systems. Unlike liquid crystal displays (LCD), a VFD emits a very bright light with clear contrast. Because the VFD emits a very bright light, the VFD is easily seen by a user even when an external light source, such as the sun, is shinning directly on the display. This contrasts to LCDs which, in some applications, have a tendency of becoming difficult for the user to see when an external light source is directly shining on the display. 
     However, VFDs have drawbacks compared to their LCD counterparts. VFDs typically use more electricity than similar size LCDs. In applications such as vehicle entertainment systems, the electricity drawn by the display is not a concern because the electrical system of the vehicle produces more than an adequate amount of electricity to properly power the VFD. Additionally, complex VFDs also have the drawback of producing a large electromagnetic field. This large electromagnetic field is a greater concern since it may interfere with other electronic components populating the circuit board or electronic modules in the vicinity. 
     Accordingly, there is a need for a system that shields electronic components populating the circuit board from the electromagnetic field produced by a VFD display. 
     SUMMARY 
     In overcoming the drawbacks and limitations of the known technologies, a system for shielding electronic components from a VFD display is disclosed. While particularly shown and described in conjunction with a VFD display, it is apparent that the system can be used with other types of displays. The system includes a circuit board, a shield and a display. The display includes a front side and a back side. The backside of the display is mounted to a mounting area of the circuit board while the front side of the display has a display area for displaying characters, such as numbers and letters, and graphics. The shield includes a face having an opening. The shield is located adjacent to the display such that the opening is located above the viewing area of the display. A wall portion extends from the face of the shield towards the circuit board, thereby substantially encapsulating the display between the circuit board, the shield and the wall portion. 
     These and other advantages, features and embodiments of the invention will become apparent from the drawings, detailed description and claims which follow. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded view of a system for shielding electronic components embodying the principles of the present invention; 
         FIG. 2  is a perspective view of the system for shielding electronic components embodying the principles of the present invention; and 
         FIG. 3  is a perspective view of the system for shielding electronic components, the system having a wall portion defining an opening. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 and 2 , a system  10  for shielding electronic components is shown. The system  10  includes as its main components a circuit board  12 , a display  14  and a shield  16 . The circuit board  12  is of a typical construction and may be any circuit board attached to a display. Such circuit boards commonly found in the head unit of an automobile entertainment system, an alarm clock or a calculator. 
     While populated with other various electronic components, the circuit board  12  includes a mounting area  17  delineating the location of where the display  14  is to be placed on the circuit board  12 . The circuit board  12  also includes a plurality of locking points  18 . As will be described later in more detail, the plurality of locking points  18  will serve to aid in the anchoring of the shield  16  to the circuit board  12 . It should be understood that although a plurality of locking points  18  are shown, a singular locking point may be utilized. To achieve this purpose, each locking point  18  is illustrated as being a through-hole, defined by the circuit board  12  that extends through the thickness of the circuit board  12 . 
     The display  14  includes a front side  20  and a back side  22 ; the front side  20  of which includes a display area  24 . When in use, the display area  24  may display characters, such as numbers and letters, or graphics. Typically, the display  14  is contemplated as being a vacuum fluorescent display (VFD), but may be any type of display including, but not limited to, a liquid crystal display. The backside  22  of display  14  is placed above the mounting area  16  of the circuit board  12 . The display  14  also includes a display connector  26 , which may be a plurality of pins. 
     The circuit board  12  includes an electrical contact area  28  made up of a plurality of electrical contacts. When the backside  22  of the display  14  is mounted to the mounting area  17 , the display connector  26  is in electrical communication with the electrical contact  28 , which provides from the circuit board  12  and/or other components requisite electrical signals to the display  14  via the display connector  26 . The electrical signals may instruct the display  14  to display characters, numbers or graphics in the display area  24 . 
     The shield  16  includes a face  30  defining an opening  32 . The shield  16  also includes wall portions  34 ,  36 ,  38 ,  40  extending substantially perpendicular from the face  30 . The wall portions  34 ,  36 ,  38 ,  40  include at least one locking peg  42 . The shield  16  may be made of tin nickel, iron, tin, steel, aluminum or combination thereof or any material suitable for suppressing an electromagnetic field generated by the display  14 . The shield  16  is coupled to the circuit board  12  such that the locking pegs  42  mechanically engage the locking points  18  of the circuit board  12  thereafter, the opening  32  of the shield  16  will allow a user to view the viewing area  24  of the display  16  through the opening  32 . 
     Generally, the locking pegs  42  extend through the thickness of the circuit board  12  when inserted into the mounting points  18 . The locking pegs  42  may attach to the portions of the circuit board  12  forming the locking points  18  by frictional engagement, an adhesive or any other suitable method. The adhesive may be a glue or a solder. 
     Referring to  FIG. 3 , another embodiment of the system  10 ′ for shielding electronic components as shown. This embodiment is similar to the embodiment shown in  FIG. 1  with the exception that the wall portion  34  has a portion removed thereby defining an opening  44 . The opening  44  allows access to the display connector  26  and the electrical contact  28 . 
     The foregoing disclosure is the best mode devised by the inventors for practicing this invention. It is apparent, however, that methods incorporating modifications and variations will be obvious to one skilled in the art of electromagnetic shielding of display systems and more particularly to electromagnetic shielding of vacuum fluorescent display systems. Inasmuch as the foregoing disclosure is intended to enable one skilled in the pertinent art to practice the instant invention, it should not be construed to be limited thereby but should be construed to include such aforementioned obvious variations and be limited only by the spirit and scope of the following claims.

Technology Classification (CPC): 7