An adaptive optics apparatus (100, 110) for correcting aberrations of an examination object comprising: light modulating means arranged to modulate light in a polarization direction of one of two polarized light components at the time of first incidence, wherein the light is emitted from a light source; and changing means arranged to rotate a polarization direction of the modulated light by 90 degrees; the light modulating means being arranged to modulate the light from the changing means so as to modulate the light in a polarization direction of the other of the two polarized light components at the time of second incidence, and the adaptive optics apparatus (100, 110) further comprising irradiating means arranged to irradiate a measurement object (8, 81) with the light modulated by the light modulating means; characterized in that the adaptive optics apparatus (100, 110) further comprises an optical system (12, 72) arranged to be located so that a surface of the light modulating means at the time of the first incidence and a surface of the light modulating means at the time of the second incidence are in an optically conjugate relationship, of the same magnification, and in an erected image relationship, wherein the light modulating means modulates return light from the measurement object (8, 81) irradiated by the irradiating means in the polarization direction of the other of the two polarized light components, the changing means rotates a polarization direction of the modulated return light by 90 degrees, and the light modulating means modulates the light from the changing means so as to modulate the light in the polarization direction of the one of the two polarized light components. light modulating means arranged to modulate light in a polarization direction of one of two polarized light components at the time of first incidence, wherein the light is emitted from a light source; and changing means arranged to rotate a polarization direction of the modulated light by 90 degrees; the light modulating means being arranged to modulate the light from the changing means so as to modulate the light in a polarization direction of the other of the two polarized light components at the time of second incidence, and the adaptive optics apparatus (100, 110) further comprising irradiating means arranged to irradiate a measurement object (8, 81) with the light modulated by the light modulating means; characterized in that the adaptive optics apparatus (100, 110) further comprises an optical system (12, 72) arranged to be located so that a surface of the light modulating means at the time of the first incidence and a surface of the light modulating means at the time of the second incidence are in an optically conjugate relationship, of the same magnification, and in an erected image relationship, wherein the light modulating means modulates return light from the measurement object (8, 81) irradiated by the irradiating means in the polarization direction of the other of the two polarized light components, the changing means rotates a polarization direction of the modulated return light by 90 degrees, and the light modulating means modulates the light from the changing means so as to modulate the light in the polarization direction of the one of the two polarized light components.