| abstract |
The present invention addresses the problem of providing an optically anisotropic layer which has excellent planarity and with which it is possible to produce an image display device having excellent contrast, and of providing an optical film, a polarizing plate, and an image display device having said layer. The optically anisotropic layer according to the present invention is obtained by immobilizing, in a smectic liquid crystal state, a polymerizable liquid crystal composition that includes a polymerizable rod-shaped liquid crystal compound exhibiting a smectic liquid crystal state, and an additive, wherein the molecular length A (Å) of the polymerizable rod-shaped liquid crystal compound, the layer spacing B (Å) of the smectic phase of the optically anisotropic layer, and the molecular length C (Å) of the additive satisfy the relationship in formula (1-1). Formula (1-1): 0.5×B ≤ C ≤ 0.6×A |