Optically anisotropic film comprising an absorption intensity ratio of 1.02 or more, laminate, circularly polarizing plate, and display device
申请人:FUJIFILM Corporation
公开号:US11353750B2
公开(公告)日:2022-06-07
Provided is an optically anisotropic film exhibiting reverse wavelength dispersibility with excellent thickness-direction phase differences, a laminate, a circularly polarizing plate, and a display device. The optically anisotropic film of an embodiment of the present invention satisfies the following Requirements 1 to 4. Requirement 1: In a case of irradiation with P-polarized light and S-polarized light, which are linearly polarized light perpendicular to each other, from a direction inclined by 45° from a normal direction of a film surface of the optically anisotropic film, an absorption intensity ratio in a case of irradiation with S-polarized light to an absorption intensity in a case of irradiation with P-polarized light is 1.02 or more in an absorption intensity at a wavelength having a largest absorption in a wavelength range of 700 to 900 nm. Requirement 2: Re(550)<10 nm, Requirement 3: Re(800)<10 nm. Requirement 4: Rth(450)/Rth(550)<1.
本发明提供了一种各向异性光学薄膜、层压板、圆偏振片和显示装置,该薄膜具有优异的厚度方向相位差,且具有反向波长色散性。本发明一个实施例的各向异性光学薄膜满足以下要求 1 至 4。要求 1:在用 P 偏振光和 S 偏振光(它们是相互垂直的线性偏振光)从与光学各向异性薄膜的薄膜表面的法线方向倾斜 45°的方向照射的情况下,用 S 偏振光照射的情况下的吸收强度与用 P 偏振光照射的情况下的吸收强度之比,在 700 至 900 纳米波长范围内吸收最大的波长处的吸收强度为 1.02 或以上。要求 2:Re(550)<10 纳米,要求 3:Re(800)<10 纳米。要求 4:Rth(450)/Rth(550)<1。