| 摘要 |
To provide an illumination device of an edge light type that has an anisotropic luminous intensity distribution of light and is able to emit light with high luminous intensity. The illumination device (1) of the edge light type includes a light emitting unit (3) provided at one side surface of a light guide plate (2). The light guide plate (2) has a plurality of recesses (6) having a V-shaped cross-section and provided on a bottom surface (2b) in parallel to an X-axis direction at a predetermined pitch and a plurality of protrusions (7) having a lenticular lens shape in the cross-sectional view and provided in parallel to a Y-axis direction at a prearranged pitch. A vertex angle of each of the recesses (6) is defined to reflect the light incident into the light guide plate (2) through an incident end surface (2a) by an inclined surface on the recesses (6) of the bottom surface (2b) such that emission light emitted from an emission surface (2c) has a maximum luminous intensity at an angle between 25 degree to 65 degree with respect to the Z-axis direction. |
