In two one type diffraction refraction compound die

摘要

PROBLEM TO BE SOLVED: To provide a two-piece type diffraction and refraction combination type image forming system.;SOLUTION: This system is constituted of a first lens and a second lens and the first lens is provided with a concave face and a convex face and the concave face is made to be an objective face. The second lens is provided with a convex face and a concave face and the convex face is directed to the convex face of the first lens and the concave face is directed to a filter. One optional face of the first lens and the second lens is made a spherical face or aspherical face. This image forming system is provided with at least one diffraction face and a diffraction and refraction combination lens face is located at one optional face of the first lens or the second lens. Then, image forming quality is raised by eliminating a large number of aberrations and the manufacturing cost is reduced and the miniaturization of the system is attained while saving the space without increasing the number of components by an optical property special to a diffracting means.;COPYRIGHT: (C)2004,JPO&NCIPI