An adaptive optics apparatus includes a first light modulating unit configured to perform modulation in a polarization direction of one of two polarized light components in light emitted from a light source, a changing unit configured to rotate the light modulated by the first light modulating unit by 90 degrees, a second light modulating unit configured to modulate the light changed by the changing unit in the polarization direction, and an irradiating unit configured to irradiate a measurement object with the light modulated by the second light modulating unit.