| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a light diffusion plate capable of being molded using a relatively small-sized existing injection molding machine and contributing to thinning of a direct backlight device while suppressing luminance irregularities of a light emitting surface. <P>SOLUTION: The light diffusion plate 1 is made by injection molding and disposed so as to close the opening of a casing. The light diffusion plate is provided with a body part 10 of a fixed thickness, which is rectangular in the plane view, an outer peripheral part 20 on the outer peripheral side of the body part, and a connection part 30 for connecting the body part to the outer peripheral part. The body part is provided with an effective illumination area on the almost center position of the rectangle and an irregular structure 12 for which the maximum value of center line average roughness is 3 to 1,000μm is formed in a range including the area. The outer peripheral part has a roughly fixed thickness thinner than the thickness of the body part and is supported by the casing. The connection part becomes thinner from the body part toward the outer peripheral part side. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
