To enhance utilization efficiency of light and to obtain uniform luminance on an exit surface by using a spot light source having directivity.
The back light device is equipped with: a light guide plate 22 whose incident surface 26 is formed at an angle part so as to intersect with one diagonal line 25a of an illumination region 25 of a rectangle to illuminate a liquid crystal display panel; and the spot light source 21 which is installed in a position deviating from the top of the one diagonal line 25a on the incident surface in the angle part of the light guide plate 22. The areas of the respective divided regions 25A, 25B of the illumination region 25 divided by the optical axis 21a of the spot light source 21 installed on the incident surface 26 are varied to evenly distribute the light from the spot light source 21 near to each of the angle parts in the other diagonal line 25b direction of the illumination region 25 intersecting with the optical axis 21a.
WAKAMIYA KIYOTAKA
KOSHIMURA AKIRA
| JP2004111384A | 2004-04-08 | |||
| JP2004055336A | 2004-02-19 | |||
| JP2001357714A | 2001-12-26 | |||
| JP2000268621A | 2000-09-29 | |||
| JP2004253318A | 2004-09-09 | |||
| JP2004241323A | 2004-08-26 | |||
| JP2004111352A | 2004-04-08 | |||
| JP2004103468A | 2004-04-02 |
Eiichi Tamura
Seiji Iga