| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a refractive power measuring apparatus permitting the accurate and stable measurement for an examined eye with a large pupil diameter and the measurement for an examined eye with a small pupil diameter. <P>SOLUTION: The refractive power measuring apparatus comprises a measuring optical system for projecting a spot luminous flux on the fundus oculi of the examined eye, taking out the reflected luminous flux from the fundus oculi around the pupil via a ring-shaped opening formed at a conjugate position with the pupil and receiving the luminous flux by a light receiving element, or a measuring optical system for projecting the luminous flux on the fundus oculi from around the pupil via the ring-shaped opening at the conjugate position with the pupil, taking out the reflected luminous flux from the fundus oculi from the center of the pupil and receiving the luminous flux by the light receiving element to measure the refractivity of the examined eye based on the output of the light receiving element. The refractive power measuring apparatus also has a variation means for varying the size of the ring-shaped opening on the pupil so that the inner diameter and the outer diameter of the opening are different and a control means for controlling the variation means based on the result of light receiving of the light receiving element. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
