Configuring ophthalmic lenses that reduce oblique aberrations based on a wearer's accommodative demand values is disclosed. The accommodative demand values include A_(rel−) and A_(rel+) depend on object vergence L. The accommodative demand values are considered to and ensure no or reduced eye strain to the wearer. An improved merit function Φ′ is calculated based on the accommodative demand values. In the calculation, accommodative term A is a smooth and continuous function of both the object distance L and the spherical component of the power error. This ensures the accommodative demand values are well below maximum relative accommodations available to the wearer to prevent eye fatigue. The calculation may also include a smooth and continuous thresholding function ƒ that optimizes the merit function. The calculation may also include evaluation of the power error associated with various object vergencies for every direction of sight.

Methods for treating presbyopia in a patient's eye involve inducing spherical aberration in a central area of the pupil. In embodiments, refractive properties of an eye are measured to obtain a baseline refractive correction. A lens for wearing on the eye is provided to create spherical aberration or a distribution of spherical aberrations beyond the baseline refractive correction in the central area of the pupil. The central area of the pupil has a diameter of between 1.5 mm and 4.0 mm and has negligible spherical aberration without the treatment.

The disclosure generally describes methods, systems and products relating to the development and manufacture of scleral contact lenses. A number of dimensions for the scleral lens is generated based on control points and attendant curvature parameters. Any change to one or more of the curve parameters imparts an improved anterior and posterior surface of the scleral lens and associated thickness, while undesired modifications to control points and other curve parameters remain static inasmuch as the sagittal depth component is an input parameter of the present disclosure.

Apparatus and methods are described, including providing a temporary progressive lens (20) that is configured for a subject's temporary use, based upon an initial progressive-lens optical design. The lens is composed of a base lens (22) and an attached additional and removable progressive lens part (24) for test purposes. Data that are indicative of suitability of the optical design for activities that are performed by the subject are received, the data being generated during use of the temporary progressive lens by the subject. Based upon the received data, the optical design for a progressive lens for the subject is optimised, and the optimised optical design in output.

The present invention relates to a progressive addition lens and to a method for manufacturing the same. A lens comprises a rear surface intended to face an eye of the user and a front surface opposite to the rear surface. The present invention is particularly related to defining the rear surface of the lens. The present invention shows that it is possible to enhance image quality by using rotational symmetry in combination with a predefined progression curve to thereby avoid astigmatic imaging and also substantially reducing the effects of spherical aberration, coma, curvature of field and distortion.

Method to establish the size of the zones of near A.sub.c, far A.sub.L and intermediate A.sub.i vision of a progressive lens by generating, thanks to virtual reality, a gaze map of the user while following a stimulus in at least two planes at two different distances. Once the gaze maps have been made in those two planes or more, the area of each zone is calculated from the maximum horizontal and vertical amplitudes and the points of maximum frequency. In this way, the lens is adapted to the way a user looks.

A contact lens having more than one configuration is disclosed herein. The optical power of the contact lens may be dynamically changed through the different configurations of the contact lens. The different configurations may be actuated using a valve. Also disclosed herein is a contact lens comprising a dimension, which contact lens is configured to have the dimension change non-linearly as a function of a pressure applied to the contact lens.

Provided is a progressive addition lens without a progressive corridor and capable of eliminating the peripheral unwanted astigmatism on both sides of the central progressive zone of the lens. The rear surface of the lens blank is processed to form a three-dimensional freeform surface, making it the lens of the present invention, which can provide a clear distance view on the top thereof, a clear near view on the bottom thereof, and a clear intermediate view thereof at the middle progressive zone. The present disclosure has a wide field of view and a high visual clarity that greatly reduces the interference of vision in the peripheral unwanted astigmatism area.

A progressive power lens and a technique associated therewith, wherein C.sub.F and Ax.sub.F are achieved in a distance portion and C.sub.N and Ax.sub.N are achieved in a near portion in a state in which: a basic progressive surface on which no astigmatic power is set in the distance portion, the near portion, and an intermediate portion; a curvature distribution of a set α (k1α, k2α) of two principal curvatures having different sizes that is uniformly added to the distance portion, the near portion, and the intermediate portion, and that achieves C.sub.F and Ax.sub.F in the distance portion; and a curvature distribution of a set β (k1β, k2β) of two principal curvatures having different sizes that is different from the curvature distribution of the set α, and in which an absolute value (lk1β-k2βl) of a principal curvature difference increases in a predetermined direction, are combined.

An amount obtained by multiplying a vector amount obtained by Fourier transform of a wavefront of a spectacle lens by a preset predetermined vector amount is adopted as an evaluation index of the spectacle lens, and the evaluation index is evaluated based on the evaluation index.