OPTICAL SYSTEM, OPTICAL DEVICE, AND METHOD FOR MANUFACTURING OPTICAL SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an optical system having a low telephoto ratio and high optical performance, while satisfactorily correcting color aberrations over the whole of a used wavelength band.SOLUTION: An optical system includes: a focus lens LF for performing focusing to an object; a diffraction optical element DOE arranged closer to an object side than the focus lens LF; and a negative lens L13 that is arranged closer to the object side than the focus lens LF and satisfies a conditional expression (1) nd2<1.89-0.00637×νd2 and a conditional expression (2)νd2>35, where a refraction index of the negative lens L13 with respect to a d-line is represented by nd2 and an Abbe number of the negative lens L13 with respect to the d-line is represented byνd2.