Patent ID: 7316480

Claim:
An eye refractive power measurement apparatus for measuring eye refractive power of an eye of an examinee, the apparatus comprising: an observation optical system having a first image pickup element which picks up an image of an anterior segment of the eye; a measurement optical system including: a projection optical system for projecting ring-shaped measurement light onto a fundus of the eye via a ring-shaped aperture arranged at an approximately conjugate position with a pupil of the eye, where a diameter on the pupil of the ring-shaped aperture is changed, and at least one of the diameter on the pupil of the ring-shaped aperture is such that measurement can be performed even to the eye with a small pupil diameter; and a photo-receiving optical system for forming a ring-shaped image on a second image pickup element by picking up the ring-shaped measurement light reflected from the fundus via a central portion of the pupil; changing means for changing the diameter on the pupil of the ring-shaped aperture; and calculation means for calculating the eye refractive power based on an image pickup result obtained by the second image pickup element.