An instrument (51) for measuring a refractive power includes a target (62a), a target projecting unit (62), a measurement light projecting unit(61a, 61i, 61b, 61c, and 61d), a light receiving unit (61h), a unit (66) for performing a normal refractive power measurement, a judgment unit (68), and a unit (67) for performing a high-speed refractive power measurement. The unit (51) for performing a normal refractive power measurement measures a normal refractive power of an examined eye based on received light data. The judgment unit (68) judges reliability of the received light data or the refractive power measurement. The unit (67) for performing a high-speed refractive power measurement measures a refractive power of the examined eye faster than the unit (66) for performing a normal refractive power measurement in response to a judgment result of the judgment unit (68).
