| 摘要 |
<p>A planar light guide (4) having a light entrance end face (41) receiving light from a spot-like primary light source and a light exit end face (43) outputting the entered light, wherein a plurality of lens arrays (42) are formed, at at least a part of the light entrance end face, to extend from the light exit end face toward the opposite face substantially in parallel with each other. The lens array (42) has an asymmetric cross-sectional shape defined by a combination of at least two different curves. When the light guide (4) is combined with a primary light source disposed oppositely to the light entrance end face (41) and a light deflecting element disposed oppositely to the light exit end face (43), a high quality planar light source having a high uniformity and no variation in luminance is provided even when a relative small number of spot-like light sources are used as the primary light source.</p> |
