Patent ID: 6850295

Claim:
A light diffusing plate comprising: a birefringent film containing dispersed therein minute regions differing from the birefringent film in birefringent characteristics; and wherein the minute regions comprise thermoplastic liquid-crystal polymers, a difference in refractive index between the birefringent film and the minute regions, in a direction Δn 1 perpendicular to an axis direction in which linearly polarized light has a maximum transmittance, is 0.03 or larger, a different in refractive index between the birefringent film and the minute regions in the axis direction Δn 2 is not larger than 80% of Δn 1 , the minute regions are dispersedly contained in the birefringent film by phase separation and each has a length in the Δn 1 direction of 0.05 to 500 μm, and the thermoplastic liquid-crystal polymer is a thermoplastic branched liquid-crystal polymer having side chains each containing a segment represented by general formula (I): —Y-Z, wherein Y is one of a polymethylene chain, a polyoxymethylene chain and a polyoxyethylene chain branching from a main chain and Z is a para-substituted cyclic compound.