A method for determining optical power of an optical lens to be placed in front of an eye of a person, the method including: a first distance determining during which a first gazing distance is determined, which is the distance between the eye of the person and a first visual stimulus when the person gazes at the first visual stimulus in a given gazing direction with a first level of attention: a second distance determining during which a second gazing distance is determined, which is the distance between the eye of the person and a second visual stimulus when the person gazes at the second visual stimulus in the given gazing direction with a second level of attention different from the first level of attention; and an optical power determining during which the optical power adapted for the person is determined based on the first and second gazing distances.

A spectacle lens is provided belonging to a series of spectacle lenses having each of first refractive power and second refractive power in common, where a progressive region length, which is a length along a meridian within a progressive region, is shorter than a predetermined reference spectacle lens belonging to the series of spectacle lenses, and a designed maximum differential value where a normalized addition refractive power distribution in the progressive region is differentiated is caused to be close to a reference maximum differential value where a normalized addition refractive power distribution in the progressive region of the reference spectacle lens is differentiated.

Apparatuses, systems and methods for providing improved ophthalmic lenses, particularly intraocular lenses (IOLs), include features for reducing dysphotopsia effects, such as haloes and glare, in extended range of vision lenses. Exemplary ophthalmic lenses can include a central zone with a first set of three echelettes arranged around the optical axis, the first set having a profile in r-squared space. An intermediate zone includes a second set of three echelettes arranged around the optical axis, the second set having a profile in r-squared space that is different than the profile of the first set. A peripheral zone includes a third set of three echelettes arranged around the optical axis, the third set having a profile in r-squared space that is different than the profile of the first set and the profile of the second set.

A pair of progressive ophthalmic lenses (1, 2) meets special conditions for improving binocular vision of a wearer, while avoiding discomfort for peripheral vision. A first one of the conditions sets a minimum value for the difference between nasal and temporal half-widths of far vision field and/or proximate vision field for at least one of the lens. A second one of the conditions sets a maximum value for the relative difference in mean refractive power gradient between both lenses.

Progressive lenses designs are disclosed having optical parameters such as the width of a far vision zone, the width of a near vision zone, the width of a corridor, the maximum residual cylinder, the maximum gradient of residual cylinder, that vary with addition. Such lens designs may provide improved performance for individuals requiring different amounts of addition (such as individuals having different ages) who spend more time performing different types of activities such as viewing hand-held devices like smart phones and tablets or reading books.

An eye-strain reducing lens is characterized by an x-y-z coordinate system, and includes a distance-vision region, having a negative distance-vision optical power, configured to refract a light ray, directed by a source at a distance-vision region point at a distance-vision x-distance from a center of the coordinate system, to propagate to an eye-center-representative location; and a near-vision region, having a near-vision optical power that matches the distance-vision optical power within 0.5 D, configured to refract a light ray, directed by the source at a near-vision region point at a near-vision x-distance from the center of the coordinate system, to propagate to an x-z location of the eye-center representative location at a corresponding y height; wherein the near-vision x-distance is smaller than the distance-vision x-distance.

A lens element worn in front of an eye of a person includes a refraction area having a first refractive power based on a prescription for correcting an abnormal refraction of the eye of the person and a second refractive power different from the first refractive power and a plurality of at least three optical elements, at least one optical element having an optical function of not focusing an image on the retina of the eye so as to slow down the progression of the abnormal refraction of the eye.

A measuring method for measuring sensitivity of eye around certain line of sight includes: showing image of predetermined pattern on a display screen showing in front of eyeball of subject by display device secured to head; showing fixation target focused on by subject, on display screen to make line of sight of subject; showing change region where predetermined pattern image is changed, at anisotropic area around intersection point or fixation target in screen is separated from intersection point and fixation target, intersection point wherein subject certain line of sight focuses on fixation target, crosses display screen; showing change region where predetermined image pattern is changed on display screen, wherein change region manner is continuously or intermittently brought close to or away from intersection point or fixation target in display screen; and determining range wherein subject senses change region by bringing it close or away from intersection point or fixation target.

The present invention relates to a transparent prescription screen protector. The transparent prescription screen protector provides a prescribed corrected power range for a user with a presbyopia vision defect. The screen protector also protects a display screen on which the cover is applied from scratches, breakage and other damage and debris. The screen protector is a multi-layer device, wherein the top layer is touch sensitive and is configured to receive the user's touch input. The bottom layer has an adhesive backing to removably secure the screen protector to the display screen. The intermediate layer has embedded prescription lenses with a prescribed power range and configured to compensate for the farsightedness vision defect of the user, thereby allowing the user to view the content displayed on the display screen clearly.

A progressive addition lens includes a first fitting point, a near vision reference point and a first optical spherical power variation between the first fitting point and the near vision reference point. The lens further includes a second fitting point and a night vision reference point located on a same face of the lens, the night vision reference point being positioned on an eye gaze direction inclined by an upward eye gaze declination angle when the user wears the progressive addition lens mounted in a frame with a downward head declination angle opposite to the upward eye gaze declination angle without moving the frame relatively to the user's face, the progressive addition lens presenting a second optical spherical power variation between the second fitting point and the night vision reference point, the night vision reference point having a lower optical spherical power than the second fitting point.