Patent ID: 8691351

Claim:
An antireflection film comprising, in a following order: a transparent substrate film; a medium refractive index layer; a high refractive index layer; and a low refractive index layer, wherein the medium refractive index layer is (A) a medium refractive index layer having a refractive index of 1.60 to 1.64 at a wavelength of 550 nm and a thickness of 55.0 to 65.0 nm, the high refractive index layer is (B) a high refractive index layer having a refractive index of 1.70 to 1.74 at a wavelength of 550 nm and a thickness of 105.0 to 115.0 nm, the low refractive index layer is (C) a low refractive index layer having a refractive index of 1.32 to 1.37 at a wavelength of 550 nm and a thickness of 85.0 to 95.0, and the color tint of regularly reflected light for 5° incident light in the wavelength region 380-780 nm of a CIE standard illuminant D65 satisfies the conditions that a* and b* values of the CIE(1976) L*a*b* color space are in the ranges 0≦a*≦2.05 and −10≦b*≦0 while the color difference at fluctuation of layer thickness is less than 2.98, wherein the color difference is measured according to the following equation: Δ E ={( L*−L *′) 2 +( a*−a *′) 2 +( b*−b *′) 2 } 1/2 wherein L*′, a*′, b*′ are values of the color tint of reflected light when the thickness of an arbitrary layer out of the low refractive index layer, high refractive index layer and medium refractive index layer is changed by 2.5% is measured.