| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical film having both type A and type B properties.SOLUTION: An optical film has a fine structure comprising high and low refractive index sections formed therein and has a property that causes circular light entering along a scattering central axis to be projected in an elliptical shape on a plane parallel to the optical film. The scattering property for the light entering along the scattering central axis includes: a relationship Tx between an exit angle in a plane defined by an X-axis in an optical film plane, which is parallel to a longitudinal direction of the elliptical shape, and the scattering central axis, and a diffuse transmittance at the exit angle; and a relationship Ty between an exit angle in a plane defined by a Y-axis of the optical film plane perpendicular to the X-axis and the scattering central axis, and diffuse transmittance at the exit angle. The relationship Tx and the relationship Ty are related such that a peak width at one-tenth of a maximum point of a diffuse transmittance peak in the relationship Tx and a peak width at one-tenth of a maximum point of a diffuse transmittance peak in the relationship Ty satisfy a specific condition. |
