Abstract: A method implemented by a computer means includes: obtaining a lens design; the lens design representing the variation of optical aberrations as a function of the angular view point; obtaining a set of subjective values representing the sensitivity of the user to a set of optical aberrations; and correlating the set of subjective values and the lens design based on the variation of optical aberrations so as to produce correlation information, advantageously for determining to which extent the lens design is adapted to the user from the correlation.

Abstract: A method implemented by a computer means includes: obtaining a lens design; the lens design representing the variation of optical aberrations as a function of the angular view point; obtaining a set of subjective values representing the sensitivity of the user to a set of optical aberrations; and correlating the set of subjective values and the lens design based on the variation of optical aberrations so as to produce correlation information, advantageously for determining to which extent the lens design is adapted to the user from the correlation.

Abstract: Toric contact or intraocular lenses having a correcting portion characterized by one or more novel constructions that each produce an optical path that improves angular misalignment tolerance. The lens may be constructed with a “smooth atoric” aspect where the optical path through the correcting portion of the lens corrects for both astigmatism and an axisymmetric aberration other than astigmatism, there being no sudden surface discontinuity between the regions that provide the different corrections (thus, “smooth”). In another embodiment, the lens may be constructed with so-called “sectors” circumferentially arranged around the optical axis such that an optical path through the correcting portion of the lens varies as a function of the angular separation from the reference meridian plane, and the correcting portion is divided into at least two sectors having different astigmatism correction axes.

Abstract: The two lenses of a pair of ophthalmic lenses are of the progressive simultaneous vision type, and in one lens the progressive profile varies so that the power is greater at the center than at the periphery, and vice versa for the other lens. The range of lenses includes two series of lenses whose nominal powers differ with a predetermined increment, for example 0.25 diopter. The method of prescribing the pair of lenses includes a standard optometric examination, determining which eye has the better tolerance to myopic defocusing and selecting a lens for each eye from a respective series of the range according to the results of the examination.

Abstract: In a method of producing tolerance markings on a contact lens for correcting astigmatism which has a given cylinder, the tolerance markings comprise at least two straight line segments in the peripheral part of the contact lens with an angle 2.alpha..sub.T between them. The angle 2.alpha..sub.T between the two straight line segments of the tolerance markings depends on the cylinder of the contact lens.