| 摘要 |
PURPOSE: To make a light quantity distribution uniform by successively disposing a scattering part and a transparent planar member adjacent to each other at a light source. CONSTITUTION: This illumination device 11 has a thin type cold cathode ray tube (light source) 5, such as fluorescent lamp, and is formed with a scattering 7 as the scattering part 7 atop the same. A transparent polycarbonate plate (PC plate) 12 as the planar member is adhered to one side of the scattering part 7. The PC plate 12 is adhered to the rear surface of a polarizing plate 3. The light emitted from the cold cathode ray tube 5, therefore, transmits the scattering part 7 and the PC plate 12 and is scattered at the time of permeating the scattering part 7. This scattered light transmits the inside of the PC plate 12 in various directions. The light beam L2 transmitting the inside of the PC plate 12 is partly reflected by the front surface (boundary) of the PC plate toward the scattering part 7 and is partly reflected and scattered by the scattering part 7. Consequently, a part of the reflected light beam L5 and the light beam L3 transmit the upper and lower polarizing plates and only the linearly polarized light beam is extracted. Further, the transmitted light beam is made incident on a liquid crystal panel, is given double refraction, is transmitted through the upper polarizing plate and is converted to two-dimensional images. |
