Patent ID: 10802187

Abstract:
A circularly polarizing plate includes: a first retardation layer having negative refractive index anisotropy; a second retardation layer having positive refractive index anisotropy; and a linear polarizer, the first retardation layer and the second retardation layer being disposed such that their optical axes are parallel to each other, the first retardation layer providing an in-plane retardation whose absolute value is |R1(λ)| to light having a wavelength of λ nm, the second retardation layer providing an in-plane retardation whose absolute value is |R2(λ)| to light having a wavelength of λ nm, the first retardation layer and the second retardation layer satisfying the following formulas (1) to (4): |R1(450)|>|R1(550)|>|R1(650)|  (1)|R2(550)|>|R1(550)|  (2)|R2(550)|−|R1(550)|>|R2(450)|−|R1(450)|  (3)|R2(650)|−|R1(650)|>|R2(550)|−|R1(550)|  (4).