| 摘要 |
PROBLEM TO BE SOLVED: To prevent the luminance unevenness with simple constitution at the time of applying to a reflection type liquid crystal display device of a front light type and using a point light source of a light emitting diode etc. for the primary light source especially, for a light transmission plate, a side light type surface light source device and a display device. SOLUTION: Projected lines 14E or grooves are formed in the light transmission plate 19 so that the illuminating light may make incident on the light transmission plate 14 from a corner, and, moreover, at least each projected line 14E or each groove and the optical path of the illuminating light going straight on from the corner may cross at right angles in the nearly central region. |
