1. Field of the Invention
The present invention generally relates to a display device. More particularly, the present invention relates to a display device for preventing electromagnetic interference.
2. Description of Related Art
The modern life style has called for a thinner and lighter display apparatus. Although the traditional display apparatus made of cathode ray tubes has its own advantages, its bulky size and the radiation emitted during display is still a problem. As a result, a new development combining optoelectronics and semiconductor manufacturing technologies, the flat panel display (FPD), including liquid crystal display (LCD), organic electro-luminescent display (OELD) and plasma display panel (PDP), has become the mainstream display product.
Referring to FIG. 1 which is a partially cross-sectional views schematically illustrating a flat display device 100, a conventional control circuit 110 is electrically connected to an outer frame 120 through a conductive sponge 112 to conduct the high frequency signal generated by the control circuit 110 to the outer frame 120, such that the interference from the high frequency signal to other electrical elements is prevented. The outer frame 120 is a bezel of the flat display device 100 and can be a metal frame. A plastic frame with colorful paint is used to cover the metal frame commonly for aesthetic feeling. The outer frame 120 can be electrically connected to the second frame 132 of the back light module 130 by another conductive sponge or a fastening element (such as a screw) to conduct the high frequency signal to the second frame 132 through the outer frame 120 for grounding. Referring to FIG. 1, the control circuit 110 and the connector 114 disposed on the conventional printed circuit board 108 both front the outer frame 120 (the control circuit 110 and the connector 114 are both disposed on the same surface of the printed circuit board 108). The other surface of the printed circuit board 108 is near the back light module 130, and the printed circuit board 108 and the second frame 132 are separated by the first frame 134 of the back light module 130, such that the ground terminal of the control circuit 110 need to be passed through the outer side of the outer frame 120 for being connected to the second frame 132 of the back light module 130. The transmitting path is longer in this situation and the influence of electromagnetic interference can not be decreased.