A device for determining a head freedom area of an optical lens adapted for a wearer looking at a specific point in a scene through the optical lens comprises at least one input adapted to obtain optical lens data representing the optical features of an optical lens, to obtain wearing data and fitting data representative of the wearing conditions and fitting parameters of the optical lens, and to obtain a specific threshold value for an optical performance criterion; and at least one processor configured for determining the head freedom area that corresponds to the head positions of the wearer that provide optical performances greater than or equal to the specific threshold value when the wearer is wearing the optical lens in given wearing conditions upon given fitting parameters and looking at the specific point in the scene through the optical lens.

Disclosed is an eyewear including: a frame headwear configured to be worn by a user, the frame headwear including a front part, and at least one lens holder, each lens holder being configured to be removably fastened to the frame headwear in a predetermined mounted position and each lens holder including an associated pair of ophthalmic lenses attached to the lens holder, each lens of the associated pair of ophthalmic lenses being configured to be movable relative to the lens holder while being attached to the lens holder.

Disclosed is an eyewear including: a frame headwear configured to be worn by a user, the frame headwear including a front part, and at least one lens holder, each lens holder being configured to be removably fastened to the frame headwear in a predetermined mounted position and each lens holder including an associated pair of ophthalmic lenses attached to the lens holder, each lens of the associated pair of ophthalmic lenses being configured to be movable relative to the lens holder while being attached to the lens holder.

Apparatus and methods are described including a progressive lens (20) that is configured to provide a far-vision correction and a near-vision correction. The progressive lens includes a single-focus, far-vision corrective lens (22) that is configured to provide only a portion of the far-vision correction, and a film (24) coupled to the single-focus, far-vision corrective lens (22). The film (24) defines a far-vision corrective portion (26) that is configured to provide the remainder of the far-vision correction, a near-vision corrective portion (28) that is configured to provide additive near-vision correction, and an intermediate portion (30) in which the film transitions between the far-vision corrective portion and the near-vision corrective portion. Other applications are also described.

Described are examples of adjustable focus glasses formed using liquid crystal. A pair of adjustable focus glasses can include a frame and two lenses arranged on the frame. In some examples, at least one of the two lenses is a lens assembly that includes a plano-concave lens, a Fresnel lens, and a liquid crystal layer between the plano-concave lens and the Fresnel lens. The plano-concave lens includes a planar surface and an opposing concave surface. The Fresnel lens includes a Fresnel surface and an opposing convex surface. The planar surface and the Fresnel surface face the liquid crystal layer. The focus position of the lens assembly can be adjusted through changing the refractive index of the liquid crystal layer, using appropriate control signals from an electronic controller. This conveniently allows the adjustable focus glasses to be multi-purpose and suitable for correcting both myopia and hyperopia.

Described are examples of adjustable focus glasses formed using liquid crystal. A pair of adjustable focus glasses can include a frame and two lenses arranged on the frame. In some examples, at least one of the two lenses is a lens assembly that includes a plano-concave lens, a Fresnel lens, and a liquid crystal layer between the plano-concave lens and the Fresnel lens. The plano-concave lens includes a planar surface and an opposing concave surface. The Fresnel lens includes a Fresnel surface and an opposing convex surface. The planar surface and the Fresnel surface face the liquid crystal layer. The focus position of the lens assembly can be adjusted through changing the refractive index of the liquid crystal layer, using appropriate control signals from an electronic controller. This conveniently allows the adjustable focus glasses to be multi-purpose and suitable for correcting both myopia and hyperopia.

A performance evaluation method for a spectacle lens comprising calculating a change rate of a first component and a change rate of a second component with a computer to calculate at least one of a distortion evaluation value and a shaking evaluation value, the first component being a component in a first direction of a prism refractive index, the second component being a component in a second direction of the prism refractive index, the distortion evaluation value being a value for evaluating a distortion regarding a spectacle lens, the shaking evaluation value being a value for evaluating a shaking regarding the spectacle lens.

An optical system is presented for use in an augmented reality imaging system. The optical system comprises a light directing device, and a projecting optical device. The light directing device is configured for directing input light, including light indicative of an augmented image to be projected and input light indicative of a real image of an external scene, to propagate to an imaging plane. The projecting optical device has a fixed field of view and has a plurality of different focal parameters at different regions thereof corresponding to different vision zones within the field of view. The projecting optical device is configured to affect propagation of at least one of light indicative of the augmented image and light indicative of the real image, such that, for each of the different regions, interaction of a part of the light indicative of the augmented image and a part of the light indicative of the real image with said region of projecting optical device directs the parts of augmented image light and real image along a substantially common output propagation path, corresponding to the focal parameter of said region.

The present disclosure relates to eyeglass and a method for adjusting incident light into eyes. The eyeglass include: a crystalline lens condition acquisition member configured to acquire a condition of a crystalline lens of a user who wears the eyeglass; a lens of eyeglass including an electrowetting dual-liquid zoom lens assembly, the electrowetting dual-liquid zoom lens assembly including insulating liquid and conductive liquid which are encapsulated and driving electrodes configured to apply a voltage to the insulating liquid and the conductive liquid; and a driving device coupled to the crystalline lens condition acquisition member and the driving electrodes and configured to adjust the voltage of the driving electrodes in the case where the crystalline lens is in a tightened condition so as to convert light transmitted through the eyeglass to parallel light.

An optical system intended to be worn in front of an eye of a wearer including an optical lens having at least a control point and an optical device that has a plurality of optical elements, the optical device being attached on a surface of the optical lens or encapsulated into the optical lens, wherein each optical element has simultaneously two different optical functions, and the optical device and the optical lens are configured so that the absolute value of the difference between a measured optical power at the control point of the optical system and the optical power corresponding to the prescription for said eye of the person is smaller than or equal to 0.12 diopter.