Instrument for measuring a refractive power

An instrument for measuring a refractive power of an examined eye, comprising:

• a target movable in an optical axis direction of the examined eye;
• a target projecting unit for projecting the target onto the examined eye;
• a measurement light projecting unit for intermittently projecting light into a pupil of the examined eye;
• a light receiving unit that receives measurement light, the measurement light being projected by the measurement light projecting unit and reflected from the examined eye while the target is at rest, and the light receiving unit outputting received light data corresponding to the measurement light;
• a unit for performing a normal refractive power measurement of the examined eye based on the received light data;
• a judgment unit for judging reliability of the received light data or the refractive power measurement;
• and
• a unit for performing a high-speed refractive power measurement of the examined eye faster than the unit for performing a normal refractive power measurement in response to a judgment result of the judgment unit.