A method comprises: disposing a physical landmark upon an eye of a user; capturing at least one image of the eye of the user with an image sensor while the eye is illuminated, wherein the image includes an image of the physical landmark and at least one other point on the surface of the eye outside of the cornea; processing the at least one image to obtain at least one metric of the eye of the user; and determining, based on the at least one metric, at least one parameter of a daily use contact lens to be worn on the eye of the user.

A method for determining a contour of a frame groove in a rim of a spectacle frame includes illuminating the rim, capturing a plurality of images of the illuminated rim from different predetermined perspectives, evaluating the captured images, and determining a spatial curve of the frame groove based on the evaluated images. The rim is illuminated along the entire circumference of the rim by directed illumination. Moreover, the evaluation of the captured images includes assigning each portion contained in the captured images to a respective surface element of the frame groove on the basis of at least one of the following properties: shadowing of the respective portion, brightness of the respective portion and phase angle of the illumination of the respective portion. Moreover, an apparatus, a computer program, a method for grinding a spectacle lens, and a computer-implemented method for determining a geometry of a spectacle lens are disclosed.

A method for purifying powdered silicon carbide is in the form of a starting material to form a silicon carbide having a purity of at least 99.9%. This method has the following method steps: providing a starting material having a grain size of less than 100 μm and a silicon carbide content with at least 98% purity; and heating the starting material in a vacuum or oxygen-free atmosphere to a temperature above 1700° C. over a period of at least 8 minutes.

Systems and methods for the real time augmented reality selection of user fitted eyeglass frames for additive manufacture are provided. 3D design files for additive manufacturing and corresponding 3D visual renderings for an augmented reality display of fitted eyeglass frames are provided using a digital inventory. Users may try-on the fitted eyeglass frames in real time using augmented reality and efficiently manufacture the eyeglass frames using 3D printing.

Provided is a process for generating specifications for lenses of eyewear based on locations of extents of the eyewear determined through a pupil location determination process. Some embodiments capture an image and determine, using computer vision image recognition functionality, the pupil locations of a human's eyes based on the captured image depicting the human wearing eyewear.

A spectacle lens for at least one eye of a user, a method for producing a spectacle lens, and a computer program product having executable instructions for performing the method for producing the spectacle lens are disclosed. The spectacle lens has a permanent marking which is or contains a diffractive structure, wherein a diffractive pattern generated by illumination of the diffractive structure is configured to be invisible upon a first kind of illumination and configured to be visible only upon a second kind of illumination. The permanent markings on the spectacle lens are, on one hand, invisible to the user or to a spectator looking at the user wearing the spectacle lens without utilizing specially selected optical aids but, on the other hand, enables continued control of the spectacle lens in front of the eye of the user by an optician or a specifically designated optical sensor.

A device for acquiring images of a pair of spectacles, including a flat surface defined by an outline having a known shape and dimensions, the flat surface having at least, on the periphery thereof: —a straightening, —a size reference, and in the centre: —an acquisition area having a homogenous, non-reflective colour, the acquisition area including at least two openings intended to support the legs of the pair, and at least one position marker representing the pupils of a wearer, so as to facilitate the height positioning of the spectacle lenses in the acquisition area.

Disclosed is a method for optical design of a pair of ophthalmic lenses for correcting spherical and cylindrical refractive errors of the eyes of a wearer, including a step of defining the need for spherical and cylindrical correction of the wearer for various viewing distances, and a step of determining the spherical and cylindrical power of the ophthalmic lenses at viewing points with various proximities, in accordance with the correction needs of the wearer. The power of at least one of the two ophthalmic lenses is determined such as to limit the deviation obtained therebetween upon adding equivalent spherical power between the viewing points with various proximities and/or varying the cylindrical power vector between the viewing points with various proximities. Also disclosed is a pair of ophthalmic lenses designed according to such a method.

A method comprises: disposing a physical landmark upon an eye of a user; capturing at least one image of the eye of the user with an image sensor while the eye is illuminated, wherein the image includes an image of the physical landmark and at least one other point on the surface of the eye outside of the cornea; processing the at least one image to obtain at least one metric of the eye of the user; and determining, based on the at least one metric, at least one parameter of a daily use contact lens to be worn on the eye of the user.

A method for determining at least one optical design parameter for a progressive ophthalmic lens intended to be fitted in a frame of a wearer, depending on the wearer's visual behaviour, includes: a) placing the wearer in a situation in which he carries out a visual task at a first working distance; b) during this task, determining at least two gaze directions of the wearer at this first working distance in a frame of reference of the wearer's head; c) determining a relative position of a surface related to the frame or to an ophthalmic lens intended to be fitted in the frame; d) determining for each gaze direction at the first working distance the intersection between this gaze direction and the surface so as to establish a map of these points of intersection on this surface; and e) deducing the sought-after optical design parameter from this map.