| 摘要 |
PROBLEM TO BE SOLVED: To provide a light diffusing board capable of reducing absorption loss caused by a polarizing board and improving luminance, hardly inducing coloring problem and applicable to a reflection type liquid crystal display device or the like. SOLUTION: This light diffusing board 1 is composed of the polymer of birefringent films 11, 13, 15 and 17 formed by dispersing and distributing fine areas (e) with different birefringent characteristics. In this case birefringence differences Δn<1> and Δn<2> between these birefringent films 11, 13, 15 and 17 and the fine areas (e) are made more than 0.03 (Δn<1> ) in a direction orthogonal to an axial direction showing the maximum transmissivity and made less than 80% of the Δn<1> (Δn<2> ) in the axial direction of the maximum transmissivity. Besides, the liquid crystal display device is composed of the lamination of at least one of polarizing board and phase difference board and this light diffusing board. The light diffusing board 1 or optical element is provided on one side or both the sides of a liquid crystal cell. Thus, linearly polarized light is transmitted in the direction of Δn<2> and linearly polarized light is scattered in the direction of Δn<1> . |
