Patent ID: 8422018

Claim:
An optical measurement apparatus comprising: a hemispherical portion having a diffuse reflection layer on an inner wall; and a plane portion, disposed to involve a substantial center of curvature of said hemispherical portion and close an opening of said hemispherical portion, having a reflection layer that faces an inner surface side of said hemispherical portion, said plane portion including: at least one of a window for introducing light to be homogenized in an integrating space formed between said hemispherical portion and said plane portion, and a window for extracting light homogenized in said integrating space; an outer portion formed of a first material chiefly causing specular reflection, and occupying at least a region of a predetermined width from an outermost circumference at which said plane portion abuts on the inner wall of said hemispherical portion; and an inner portion formed of a second material chiefly causing diffuse reflection and having a higher reflectance for at least an ultraviolet region than said first material, and occupying a region inside said outer portion.