公开(公告)号：EP1600803A4

公开(公告)日：2006-08-09

申请号：EP04716352

申请日：2004-03-02

申请人： NALUX CO LTD

发明人： HATADE KOUEI ,  SAKAGAMI NORIHISA

IPC分类号： G02B13/18 ,  G02B27/42 ,  G02B13/00

CPC分类号： G02B27/42 ,  G02B5/1895 ,  G02B13/18 ,  G02B27/4211

摘要： An imaging optical system capable of being reduced in field curvature and astigmatism with requirements for small size and low cost fulfilled. The system comprises at least one optical element at least one surface of which is divided into at least one stripe-form area surrounding the optical axis and a center area including the optical axis so as to compensate for field curvature and/or astigmatism due to the imaging optical system, with step difference provided between at least one stripe-form area and the center area. According to one embodiment of this invention, the profiles of the surfaces constituting the at least one strip-form area and the center area are individually determined so as to further compensate for field curvature and/or astigmatism due to the imaging optical system.