Patent ID: 7407289

Claim:
An optometry apparatus, comprising: an optical system for projecting an index for cross cylinder test to an eye to be examined; a cross cylinder lens for forming one pair of projection images of the index by a change in astigmatic axial angle while predetermined astigmatic power is set, the cross cylinder lens being disposed on an optical axis of the optical system; operating means for inputting a result of comparison between appearance states of the pair of projection images of the index, wherein the optometry apparatus is adapted to perform a subjective measurement of measuring an astigmatic axial angle of the eye to be examined based on an input content from the operating means; initial value setting means for determining an astigmatic axial angle of the cross cylinder lens which causes one of the pair of projection images of the index to be clearly visually recognized and causes the other of the pair of projection images of the index to be visually recognized in a blurred state based on an objective value of astigmatic power of the eye to be examined and an objective value of the astigmatic axial angle of the eye to be examined, which are measured in advance, and for setting the determined astigmatic axial angle as an initial value for the subjective measurement of an astigmatic axial angle measurement; storing means for storing an amount of shift from the objective value of the astigmatic axial angle, which is necessary to cause the one of the pair of projection images to be clearly visually recognized and cause the other of the pair of projection images to be visually recognized in the blurred state, in association with the objective value of the astigmatic power in advance, wherein the initial value setting means determines the amount of shift from the storing means, said amount being associated with the previously measured objective value of the astigmatic power of the eye to be examined, and shifts the previously measured objective value of the astigmatic axial angle of the eye to be examined by the determined amount of shift to determine the initial value; and control means for changing the astigmatic axis angle of the cross cylinder lens beginning from the initial value.