An ophthalmologic apparatus includes an aberration measuring unit configured to measure wavefront aberration of returning light, and a reflective optical modulation device configured to modulate the returning light. A control unit controls the reflective optical modulation device to correct the wavefront aberration of the returning light based on a measurement result of the aberration measuring unit. The reflective optical modulation device includes a reflection mirror of which the diameter of an effective region (effective diameter) that reflects the measurement light or the returning beam is 7.5 mm or less, and 61 or more actuators that act on the reflection mirror within the effective diameter. Each of the actuators includes an interdigital electrode having a maximum displacement of 7.5 μm or more.
