Patent ID: 7405878

Claim:
An optical film, comprising: an anisotropic film having a first refractive index for a first ray and a second refractive index for a second ray, the first ray and the second ray being included in a light that is incident upon the anisotropic film from a first side in an incident direction, the first ray is polarized in a first direction that is substantially perpendicular to the incident direction, the second ray is polarized in a second direction that is substantially perpendicular to the incident direction, the second ray comprising a first component and a second component, the first ray and the second component of the second ray irradiate from the anisotropic film; an isotropic film provided below the anisotropic film, the isotropic film having a third refractive index that is substantially identical to the first refractive index such that the first ray and the second component of the second ray pass through the isotropic film; a λ/4 phase difference film provided below the isotropic film to delay a wavelength of the first ray and the second component of the second ray by approximately λ/4 when the first ray and the second component of the second ray pass through the λ/4 phase difference film; and a λ/2 phase difference film partially formed below the λ/4 phase difference film to delay the wavelength of the second component of the second ray by approximately λ/2 when the second component of the second ray passes through the λ/2 phase difference film and irradiates toward a second side that is opposite to the first side.