METHOD FOR DESIGNING EYEGLASS LENS

A sensation of a subject felt when to-be-evaluated lenses are actually worn is objectively evaluated, and is reflected in lens design. [Solution Means] A plurality of to-be-evaluated lenses that differ in lens surface design from each other are prepared in an evaluation-value calculating step, thereafter subject's predetermined biological information, such as brain waves, are measured for each of the to-be-evaluated lenses by allowing the subject to wear each of the to-be-evaluated lenses, and an evaluation value for each of the to-be-evaluated lenses is calculated relative to a predetermined index in the brain waves, for example, relative to a "state of being under stress . " Thereafter, a correlation between an evaluation value for each of the to-be-evaluated lenses calculated in the evaluation-value calculating step and a lens surface shape of each of the to-be-evaluated lenses is calculated as an index characteristic in a lens-surface-shape determining step, thereafter a lens surface shape of a suitable spectacle lens in the index is determined based on the index characteristic, and the lens surface shape is fed back as a shape of a to-be-evaluated lens of the evaluation-value calculating step.