imaging optical system a diffraction grating lens, using the imaging device and

摘要

An imaging optical system includes a diffraction grating one lens, and a diaphragm having at least composed of a diffraction grating from the diffraction ring-shaped zone of q the imaging optical system of the present invention, wherein the diffraction grating lenses of said at least one surface diffraction grating is provided, a lens surface closest to the diaphragm, the width of the diffraction ring-shaped zone 1 th counted from the optical axis side of the optical system, a second, m-1 th, m-th respectively, assuming that _2, P _m-1, P _m P 1, P, _m one satisfying the following (Expression 3) at least, an imaging optical system satisfying the 3 m ≦ q. [3] The number