System for determining a subjective value of an optical feature of at least a corrective lens adapted to an eye of a subject and associated method

A system for determining a value of a magnitude associated with a subjective value of an optical feature of a corrective lens adapted to an eye of a subject, said optical feature being applicable to compensate for a visual defect of the subject, by implementing a subjective test where the subject is asked to describe his visual performance in a plurality of real optical conditions by choosing one descriptive answer among a set of possible descriptive answers, each real optical condition of said plurality of real optical conditions comprising a value of an other optical feature of an optical component placed in front of the eye of the subject, the system comprising:

• a computer with one or more memory and one or more processor, wherein:
• an initial model giving a probability of each descriptive answer of the set of possible descriptive answers for each theoretical optical condition of a plurality of theoretical optical conditions is stored in one of said one or more memory of said computer, and
• said one or more processor of said computer is programmed to:
• a) collect results of said subjective test, performed by asking the subject to describe his visual performance in each real optical condition of said plurality of real optical conditions by choosing, for each real optical condition, one descriptive answer among said set of possible descriptive answers, said results comprising each descriptive answer chosen and the corresponding real optical condition, and
• b) determine the value of said magnitude by taking into account said initial model and each descriptive answer collected.