Device for measuring visual acuity

摘要

A device comprises a refraction correcting part 700 for correcting refraction of an eye 400 to be examined of a subject; an adjusting state measuring part 800 for measuring whether a target observed by the eye 400 through the refraction correcting part 700 is in the adjustable range of the eye; and corrective value correcting means 360 for correcting a corrective value for the refraction correcting part 700 so that said eye can achieve best correction based on a result of measurement by the adjusting state measuring part 800, and is configured to measure visual acuity characteristics of the eye 400 at a corrective value for the refraction correcting part 700 to achieve best correction of the eye 400 according to responses of the subject about displayed targets.