PROBLEM TO BE SOLVED: To provide a technology to prevent a lack of a wavefront detection light while eliminating an influence of reflection from an objective lens.SOLUTION: An ophthalmologic apparatus includes an objective lens 103, a wavefront measurement projection system 30 for irradiating a measurement light onto the ocular fundus 101a of an eye 101 to be examined through the objective lens 103, a wavefront measurement detection system 40 for receiving a reflection light from the ocular fundus 101a of the measurement light and detecting refractive characteristics of the eye 101 to be examined, and a variable optical diaphragm 43 that can move on an optical axis and vary a diaphragm diameter. The diaphragm diameter is made relatively large in a first state in which the position of the variable optical diaphragm 43 on the optical axis is not in an ocular fundus conjugate position of the ocular fundus 101a, and the diaphragm diameter is made relatively small in a second state in which the position of the variable optical diaphragm 43 on the optical axis is in the ocular fundus conjugate position of the ocular fundus 101a.SELECTED DRAWING: Figure 1【課題】対物レンズからの反射の影響を排除しつつ、同時に波面検出光の欠落を生じさせない技術を提供する。【解決手段】対物レンズ１０３と、対物レンズ１０３を介して被検眼１０１の眼底１０１ａに測定光を照射する波面計測投影系３０と、前記測定光の眼底１０１ａからの反射光を受光し被検眼１０１の屈折特性を検出する波面計測検出系４０と、光軸上で移動可能で、絞り径を可変できる可変光学絞り４３とを備え、光軸上における可変光学絞り４３の位置が眼底１０１ａの眼底共役位置にない第１の状態において、前記絞り径を相対的に大きくし、光軸上における可変光学絞り４３の位置が眼底１０１ａの眼底共役位置にある第２の状態において、前記絞り径を相対的に小さくする。【選択図】図１
