To provide a light guide member for emitting plane light and easy to be miniaturized.
A plurality of groove parts 321a are provided in one surface of a nearly flat light guide plate 321, which has a nearly wedged cross section formed thick in one end side in the lateral direction, along the vertical direction. The groove parts 321 are formed into a waveform in the vertical direction in the condition that a phase thereof is displaced from the adjacent groove part 321a. A spectral range 321c is provided on a thick side of the other surface of the light guide plate 321, and others are formed into a diffusion range. The spectral range 321c is provided with light guide projections crossing the lateral direction of the light incident direction and formed into a grid. A plurality of curved grooves 321d1 are provided into a waveform along the lateral direction in the diffusion range. Adjacent curved groove parts 321d1 are provided so that phase thereof is displaced from each other. A reflecting sheet is provided in the surface provided with the groove parts 321c. Even in the case of using a point light source for incidence of the light from an end surface on the thick side, the light can outgoes with the nearly even distribution from the nearly whole surface.
PIONEER SEIMITSU KK
Kanji Nakayama
Tsuyoshi Ishizaki
Next Patent: CONNECTION SET FOR POWER RECEPTACLE AND PLUG