| 摘要 |
A downstream emissive backlight system is provided to offer a uniform emissive distribution at a low manufacturing cost, and to use an inexpensive LED, then to employ a smaller number of LEDs, thereby cutting down the manufacturing cost to the maximum. A flexible circuit board(101) is equipped. A dome-shaped key switch(111) is disposed in an upper part of the flexible circuit board. An optical film(150) covers the dome-shaped key switch and the flexible circuit board. A light source is disposed in one side portion on top of the flexible circuit board, and is arranged to make light incident toward an upper surface of the optical film by bending the one side portion of the flexible circuit board upwards. |
