Patent ID: 7394601

Claim:
An optical system comprising: an optical member made of a solid material being a mixture in which inorganic particles are dispersed in a transparent medium, the optical member having refracting surfaces on sides from which light enters and from which light exits, wherein the solid material satisfies the following expressions: −2.100×10 −3 ·νd+ 0.693 <θgF; 0.555<θgF<0.9; νdp<35; νdn<30; and Vn<0.35, where νdp represents the Abbe number of the transparent medium, νdn represents the Abbe number of the inorganic particles, νd represents the Abbe number of the mixture, θgF represents a partial dispersion ratio (Ng−NF)/(NF−NC) of the mixture and Ng, NF, and NC are refractive indices of the mixture for the g, F, and C lines respectively, and Vn represents the volume ratio of the inorganic particles to the transparent medium.