A novel optical film is provided that exhibits a wavelength dispersion (a reverse wavelength dispersion) such that the birefringence of the film decreases as the wavelength becomes shorter, at least in the visible light range. The optical film includes a layer formed of a resin (A) having a heteroaromatic group or a molecular structure represented by the following formula (1), (2) or (3):
where in the formula (1), n is a natural number in the range of 1 to 4, and R1 and R2 each independently represent a hydrogen atom or a methyl group. The optical film exhibits a wavelength dispersion such that the birefringence of the film decreases as the wavelength becomes shorter, at least in the visible light range.
                            本发明提供了一种新型光学薄膜,它具有波长色散(反向波长色散)特性,至少在可见光范围内,薄膜的双折射随波长变短而减小。该光学薄膜包括一层由具有杂芳香族基团或下式 (1)、(2) 或 (3) 所代表的分子结构的
树脂 (A) 形成的薄膜:
式(1)中,n 是 1 至 4 范围内的自然数,R1 和 R2 各自独立地代表氢原子或甲基。该光学薄膜具有波长色散特性,至少在可见光范围内,薄膜的双折射随波长变短而减小。