To provide a lighting unit of low power consumption that can prevent a dark part from being formed at a side end part of of a light guide plate on the side of a light emitting element and uniformly and brightly light a large area.
A front light (lighting unit) is equipped with the light guide plate 12, an intermediate light guide body 13 arranged along one end surface of the light guide plate 12, and the light emitting element 15 which is arranged on a lengthwise end surface of the intermediate light guide body 13, and extension directions of respective prism grooves 14 formed on one surface side of the light guide plate 12 are set crossing a light incidence surface 12a; and the diffusion sheet 50 is interposed between the light incidence surface 12a of the light guide plate 12 and a projection surface 13k of the intermediate light guide body 13, and the diffusion sheet 50 has its a diffusing body formation surface 51a provided on one surface facing the light incidence surface 12a of the light guide plate 12 and the diffusing body formation surface 51a is varied in diffusion coefficient in accordance with the distance from the light emitting element.
YAMASHITA TATSUMARO
| JP2000222925A | 2000-08-11 | |||
| JPH09136354A | 1997-05-27 | |||
| JP2000352607A | 2000-12-19 | |||
| JP2002014208A | 2002-01-18 | |||
| JPH09159810A | 1997-06-20 | |||
| JPH10293817A | 1998-11-04 | |||
| JP2000011723A | 2000-01-14 |
Tadashi Takahashi
Takashi Watanabe
Masakazu Aoyama
Suzuki Mitsuyoshi
Kazuya Nishi
Yasuhiko Murayama