Patent ID: 7329981

Claim:
An optical filter disposed on a substrate with transparency and having a maximum absorption wavelength (λ) in a wavelength range of 575±20 nm in connection with a wavelength range from 450 to 650 nm, wherein the optical filter is configured to satisfy a relationship, 0.65 ≦T 1(λ)/ T 2(λ)≦0.90 where T 1 (λ) is a transmittance at a central part of the substrate at said maximum absorption wavelength λ, and T 2 (λ) is a transmittance at a peripheral part of the substrate at said maximum absorption wavelength λ, and the optical filter is configured to satisfy a relationship, 0.90≦( T 1(λ1)/ T 2(λ1))/( T 1(λ)/ T 2(λ))≦1.05 with respect to transmittances at wavelengths λ 1 and λ, wherein λ 1 is each wavelength of 450 nm, 530 nm and 630 nm and λ is said maximum absorption wavelength.