Patent ID: 7540617
Filing Date: 2009-06-02
Classification: G02B,G03B

Abstract:
1. An illumination optical apparatus comprising: a first fly-eye lens having a plurality of lens cells arranged along two directions orthogonal to each other and to an optical axis; a second fly-eye lens having a plurality of lens cells arranged along two directions orthogonal to each other and to said optical axis; a first lens holding member holding said first fly-eye lens; a second lens holding member joined to said first lens holding member, and holding said second fly-eye lens; and a third lens holding member joined to said second lens holding member, and holding an optical lens; wherein an illumination area is formed as a result of each shape of a lens cell aperture of said first fly-eye lens being projected by said second fly-eye lens and said optical lens to be enlarged, and said first lens holding member and said second lens holding member are joined to be relatively rotatable about said optical axis.