| 摘要 |
Provided is an edge-light type illumination device (1) capable of increasing luminance directly thereunder and capable of providing anisotropy to the luminance distribution. Light to be emitted from an emission surface (2d) of a light-guide plate (2) fulfils a condition (1) E total / E m > 2.0 and a condition (2) E total (20°,0°) = E total (20°,90°) > 1.2. Here, average intensity of light to be emitted from the emission surface (2d) is E m and total light intensity of the light to be emitted in a Z-axis direction is E total , the total light intensity E total (20°, 0°) of the light to be emitted is £” Pi (20°,0°)/”É when an angle ¸ of the light to be emitted relative to a Z-axis direction is 20° and an angle Õ of the light to be emitted relative to an X-axis direction is 0°, and the total light intensity E total (20°, 90°) of the light to be emitted from the emission surface (2d) is £” Pi /(20°,90°)/”É when the angle ¸ of the light to be emitted relative to the Z-axis direction is 20° and the angle Õ of the light to be emitted relative to the X-axis direction is 90°. |
