Patent ID: 8123356

Claim:
An amplitude of accommodation measuring apparatus comprising: a display member that displays an image for focusing at a far point side and a near point side; an optical system for observing the image displayed on the display member; a driving member that moves the optical system along an optical axis according to an instruction given from outside; and a control member that calculates the amplitude of accommodation on the basis of a position where the image starts blurring from a far point side focus position by moving the optical system to the far point side by means of the driving member, and a position where the image starts blurring from a near point side focus position by moving the optical system to the near point side by means of the driving member, and controls the driving member such that a moving speed of the optical system toward the far point side from a far point side focus position of the image to a position where the image starts blurring is less than a moving speed of the optical system toward the far point side from an initialize position to the far point side focus position of the image, and a moving speed of the optical system toward the near point side from a near point side focus position of the image to a position where the image starts blurring is less than a moving speed of the optical system toward the near point side from the initialize position to the near point side focus position of the image.