Patent ID: 8000012

Claim:
An optical multilayer film comprising: a base material formed of polyester having a refractive index of η1; a first adhesion layer having a refractive index of η2 on said base material; a second adhesion layer having a refractive index of η3 on said first adhesion layer; and a surface layer having a refractive index of η4 on said second adhesion layer, wherein said η1, η2, η3 and η4 satisfy a formula (1), (η1/η4) 1/2 ×0.95≦η2/η3≦(η1/η4) 1/2 ×1.05 (1); and wherein d1 (nm) as a thickness of said first adhesion layer and said η2 satisfy a formula (4), and d2 (nm) as a thickness of said second adhesion layer and said η3 satisfy a formula (5), at a wavelength λ of visible light in a range of 550 nm to 600 nm, −30≦ d 1−{λ/(4×η2)}≦30 (4) −30≦ d 2−{λ/(4×η3)}≦30 (5).