| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical sheet which has superior total light-beam transmissivity and also has remarkably high optical functions such as a light diffusing function, a function of refraction to a normal direction side, and a light converging function, and to provide a back light unit which can be improved more in quality such as, higher luminance to its front direction and leveling of luminance and made thinner by using the optical sheet. <P>SOLUTION: The optical sheet 1 which is equipped with a transparent base material layer 2 and an optical layer 3 laminated on the surface side of the base material layer 2 is characterized in that the optical layer 3 has spherical resin beads 5 in a binder 4 and the internal haze is 5 to 30%. The refractive index rate of the binder 4 and the resin beads 5 is preferably 0.95 to 1.05. The binder 4 is preferably formed of a polymer composition containing polyol. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
