| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a backlight unit which has thinner thickness, not depending on a dimension and a shape of a detecting portion of an optical sensor. <P>SOLUTION: The display device 3 includes a liquid crystal display panel 5 and a backlight unit 1 provided below the liquid crystal display panel 5. The backlight unit 1 has a light guide plate 7 and the light guide plane 7 has an extended portion 20 extending beyond a display range of the display device 3. The extended portion 20 has a concave portion 22 which has an optical sensor 11. The optical sensor 11 has a sensor base board 13, and a part of the sensor base board 13 is connected with the light guide plate 7 by a pressure-sensitive adhesive double-coated tape. Since the optical sensor 11 is provided in the concave portion 22, a thickness of the backlight unit 1 has no effect on a size of the optical sensor 11. As a result, the backlight unit 1 can be made thinner, not depending on a dimension and a shape of a detecting portion (a light receiving portion 25) of the optical sensor 11. <P>COPYRIGHT: (C)2009,JPO&INPIT |
