1. A correction data generation method of generating correction data used to correct a focal plane position of a lens in consideration of symmetry of a spread of PSF (point spread function) in an optical system, comprising: a binarization step of binarizing an intensity of the PSF using a predetermined threshold value level; a minimum circle calculation step of calculating a minimum circle that circumscribes the PSF binarized in the binarization step for each of a plurality of regions of an image; a PSF evaluation step of evaluating the PSF of the entire image on the basis of a weighted average value of radii of the minimum circles for the plurality of regions of the image, which are calculated in the minimum circle calculation step; and a correction data calculation step of calculating correction data used to correct the focal plane position of the lens on the basis of an evaluation value acquired in the PSF evaluation step.