| 摘要 |
Provided is an edge light-type illumination device capable of increasing luminance directly thereunder and capable of providing anisotropy to the luminance distribution. Light emitted from an emission surface (2d) of a light-guide plate (2) fulfills a condition (1) Etotal / Em > 2.0 and a condition (2) Etotal(20°, 0°) / Etotal(20°, 90°) > 1.2. The average intensity of the light emitted from the emission surface (2d) is Ｅm, the total light intensity of the light emitted in the Z axis direction is Etotal, the total light intensity (Etotal(20°, 0°)) of the light emitted when the angle (theta) of the emitted light relative to the Z axis direction is 20° and the angle (Phi) of the emitted light relative to the X axis direction is 0° is Sigma△Pi(20°, 0°)/ △omega, and the total light intensity (Etotal(20°, 90°)) of the light emitted from the emission surface (2d) when the angle (theta) of the emitted light relative to the Z axis direction is 20° and the angle (Phi) of the emitted light relative to the X axis direction is 90° is Sigma△Pi(20°, 90°)/ △omega. |
