Patent ID: 8652619

Claim:
A diffractive optical element comprising: a body being composed of a first optical material containing a first resin, and having a diffraction grating on a surface thereof; and an optical adjustment layer being composed of a second optical material containing a second resin, and provided on the body so as to cover the diffraction grating, wherein, the first optical material has a refractive index which is smaller than a refractive index of the second optical material; the refractive index of the first optical material has a wavelength dispersion which is greater than a wavelength dispersion of the refractive index of the second optical material; a difference in solubility parameter between the first resin and the second resin is no less than 0.8 [cal/cm 3 ] 1/2 and no more than 2.5 [cal/cm 3 ] 1/2 ; and the second resin contains an acrylate resin including an OH group.