Abstract: A method of preparing an ophthalmic lens (30) to be fitted into a surround of a spectacle frame, includes: acquiring a longitudinal profile (50) of the surround; centering the longitudinal profile; acquiring the geometry of at least one part of an optical face of the ophthalmic lens; calculating a treatment setpoint for treating the ophthalmic lens; and treating the ophthalmic lens. The acquiring operation includes a step of calculating the bidimensional coordinates of a plurality of measurement points (P?i, P?i) situated along two distinct longitudinal strands (51, 52) which are chosen in such a way that they define between them a band which extends along the longitudinal profile, and a step of examining the ophthalmic lens to acquire the tridimensional coordinates for the measurement points with a view to calculating the treatment setpoint.

Abstract: There is provided an eyepiece lens which has a long length from an image display surface to a first lens, a high observation magnification, and a large apparent field of view. An eyepiece lens used to observe an image displayed on the image display surface includes a first lens with a positive refractive power, a second lens with a negative refractive power, and a third lens with a positive refractive power sequentially from the image display surface side to the observation side. The lens surface of the first lens on the image display surface side has a convex shape on the image display surface side. The lens surface of the second lens on the observation side has a concave shape on the observation side. The focal length of the eyepiece lens, the focal length of the lens surface, and the focal length of the lens surface are set appropriately.

Abstract: A zoom lens including a first lens group and a second lens group is provided. Refractive powers of the first lens group and the second lens group are respectively negative and positive. The first lens group includes a first lens, a second lens, and a third lens arranged in sequence from an object side to an image side. The second lens group is disposed between the first lens group and the image side, and includes a fourth lens, a fifth lens, a sixth lens, a seventh lens, and an eighth lens arranged in sequence from the object side to the image side. The zoom lens satisfies ?2.4<f1/fw<?1.0, wherein f1 is the effective focal length of the first lens group, and fw is the effective focal length of the zoom lens at a wide end.

Abstract: Provided is a zoom optical system which includes, in order from an object, a first lens group having negative refractive power and other lens groups, and in which an interval between each lens group changes upon zooming, wherein the first lens group includes a first negative lens which is disposed closest to the object and has a diffractive optical element on an image side lens surface, and a positive lens disposed closer to the image than the first negative lens, and the glass material used for the positive lens satisfies the following conditions expressions: ?1p?35 and ?(?g, F)?0.

Abstract: A compact low-profile low-cost imaging lens with an F-value of 2.5 or less and a wide field of view which corrects aberrations properly. Its elements are arranged from an object side: a first positive optical element group including a first positive lens having a convex object-side surface and a second negative lens having a concave image-side surface; a second positive optical element group including a third positive lens having a convex image-side surface; and a third negative optical element group including a fourth negative double-sided aspheric lens having a concave image-side surface and a fifth double-sided aspheric lens having a concave object-side surface. The fourth lens image-side surface has at least one pole-change point off an optical axis. A double-sided aspheric aberration correction optical element with virtually no refractive power is located in an air gap between the first and second optical element groups.

Abstract: A system for the supply of ophthalmic lenses and related methods for providing ophthalmic lenses for enhanced experience based on right-handedness and left-handedness.

Abstract: Combined equipment for non-contacting determination of axial length (AL), anterior chamber depth (VKT) and corneal curvature (HHK) of the eye, are also important for the selection of the intraocular lens IOL to be implanted, particularly the selection of an intraocular lens (IOL) to be implanted, preferably with fixation of the eye by means of a fixating lamp and/or illumination through light sources grouped eccentrically about the observation axis.

Abstract: An object of the present invention is to provide a low-cost, miniature, wide-angle high-zoom-ratio zoom lens that has high imaging performance, and an imaging apparatus equipped with the zoom lens. To achieve the object, a zoom lens including a first lens group having positive refracting power, a second lens group having negative refracting power and a third lens group having positive refracting power in order from an object side in which a lens group P having positive refracting power is arranged closer to an image plane side than the third lens group.

Abstract: A system for determining biomechanical properties of corneal tissue includes a light source configured to provide an incident light and a confocal microscopy system configured to scan the incident light across a plurality of cross-sections of corneal tissue. The incident light is reflected by the corneal tissue as scattered light. The system also includes a filter or attenuating device configured to block or attenuate the Rayleigh peak frequency of the scattered light, a spectrometer configured to receive the scattered light and process frequency characteristics of the received scattered light to determine a Brillouin frequency shift in response to the Rayleigh peak frequency being blocked or attenuated by the filter or attenuating device, and a processor configured to generate a three-dimensional profile of the corneal tissue according to the determined Brillouin frequency shift. The three-dimensional profile provides an indicator of one or more biomechanical properties of the corneal tissue.

Abstract: A microscope immersion objective having a numerical aperture of NA>1.36 includes a front lens group. The front lens group has a first, object-side optical element having a plane parallel plate and a second optical element having a hyper-hemisphere. The plane parallel plate is wrung together with a planar side of the hyper-hemisphere.

Abstract: An imaging lens system includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, and a fifth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element with negative refractive power has a convex object-side surface and a concave image-side surface. The third lens element with negative refractive power has a concave image-side surface and the image-side surface having at least one inflection point in an off-axis region. The fourth lens element with positive refractive power has a concave object-side surface and a convex image-side surface. The fifth lens element with negative refractive power has a concave object-side surface and a concave image-side surface with at least one convex shape in an off-axis region.

Abstract: An imaging lens provided with a negative first lens group and a positive second lens group disposed in order from the object side. The first lens group is composed of a first group first lens which is a biconcave negative single lens, and the second lens group is composed of a positive second group first lens, an aperture stop, a positive second group second lens, and a negative second group third lens disposed in order from the object side. The second group second lens and second group third lens are cemented to form a cemented lens. The imaging lens is configured to satisfy conditional expressions (2): 0<fg2/f<1.3, (2b?): 0.5<fg2/f<1.25, and (6): 31<?d2 <70 at the same time, where fg2 is combined focal length of the second lens group, f is focal length of the entire lens system, and ?d2 is Abbe number of the second group first lens.

Abstract: An ophthalmic endo-illumination system includes a light source that produces a light beam, a fiber port that receives an optical fiber, a condenser that couples at least a portion of the light beam into the optical fiber received at the fiber port, and a beam splitter disposed between the fiber port and the condenser. The beam splitter is configured to receive the light beam from the condenser and split the light beam into a first beam which is coupled to the optical fiber and a second beam which is coupled to a monitoring fiber. An optical sensor is provided to detect an amount of the second beam output from the monitoring fiber. The coupling efficiency of the first beam coupled into the optical fiber may be determined based on the amount of the second beam output from the monitoring fiber.

Abstract: An imaging lens substantially consists of a first lens-group, a stop and a second lens-group in this order from an object-side. The first lens-group substantially consists of three or less lenses including at least one negative lens and a positive lens. The second lens-group substantially consists of a 21st lens-group and a 22nd lens-group in this order from the object-side. The 21st lens-group substantially consists of three or less lenses and has positive refractive-power. The 22nd lens-group substantially consists of two lenses of a negative lens and a positive lens in this order from the object-side. Predetermined conditional formulas about distance on an optical-axis from a most-object-side lens surface in an entire system to an image-plane, maximum image height, distance on the optical-axis from a most-object-side lens surface in the first lens-group to a most-image-side lens surface in the second lens-group, and focal-length of the entire system are satisfied.

Abstract: An optometric apparatus includes an optotype presenting optical system for presenting part of a plurality of optotypes corresponding to visual acuity to be measured to an examinee's eye and a visible light source for irradiating illumination light to the optotypes presented to the eye through the optotype presenting optical system. A controller is configured to execute processing of changing a light amount of the illumination light to be irradiated to the optotypes from the visible light source between a predetermined first light amount and a second light amount lower than the first light amount and processing of switching the optotypes to be presented to the eye at the time of changing the light amount of the illumination light from the first light amount to the second light amount.

Abstract: An imaging lens system comprises, in order from an object side to an image side: a first lens element with positive refractive power having a convex object-side surface; a second lens element with refractive power; a third lens element with refractive power having object-side and image-side surfaces being aspheric, at least one surface thereof having at least one inflection point; a fourth lens element with refractive power having a concave object-side surface and a convex image-side surface; a fifth lens element with refractive power having an aspheric object-side surface and an aspheric concave image-side surface, the image-side surface thereof having at least one inflection point.

Abstract: An imaging optical system, includes: in the order from an object side to an image plane side, a first lens group having a first lens which is formed as a negative lens; a second lens group having a second lens which is formed as a plano-concave lens, a third lens which is formed as a negative meniscus lens, and a fourth lens which is formed as a biconvex lens; an aperture stop; a third lens group having a fifth lens which is formed as a biconvex lens, and a sixth lens which is formed as a biconcave lens; and a fourth lens group having a seventh lens which is formed as a negative meniscus lens.

Abstract: This invention relates to a method for providing markers for evaluating and/or practicing the visual field recognizable by an eye, and/or eyes, and/or visual system of a person. The method relies on the reporting of the person of identifications of fixation objects only identifiable when the eye or eyes of the person are accurately fixated on the fixation object. Accordingly active monitoring of a saccade, if a saccade triggering stimulus is employed; or smooth pursuit, if smooth pursuit triggering stimulus is employed, of the eye of the person is not needed for determining whereto to eye or eyes are fixated. The present invention also relates to the use of a system employing the method of the invention. The present invention further relates to a system for the method of the invention and a software product for the system.

Abstract: A zoom lens assembly for monitor and a monitoring device are provided. The lens assembly comprises a first to a thirteenth lenses (L1-L13) arranged successively coaxially along the transmission direction of an incident light beam. The first, the eighth, the tenth and the twelfth lenses (L1, L8, L10 and L12) are biconvex positive lenses; the second, the ninth and the eleventh lenses (L2, L9 and L11) are falcate negative lenses; the third, the fourth, the sixth and the thirteenth lenses (L3, L4, L6 and L13) are falcate positive lenses; the fifth lens (L5) is a biconcave negative lens; and the seventh lens (L7) is a plano-concave negative lens. The second and the third lenses (L2 and L3) are closely adhered to each other, and the sixth and the seventh lenses (L6 and L7) are closely adhered to each other.

Abstract: A zoom lens consists of a negative first lens group, a stop, a positive second lens group, a negative third lens group, a positive fourth lens group, and a positive fifth lens group in this order from the object side. The first lens group through the fourth lens group move along the optical axis while changing magnification such that the distance between the first lens group and the second lens group is reduced and the distance between the second lens group and the third lens group is increased. The fifth lens group is fixed with respect to an image surface while changing magnification. The first lens group consists of a first lens, a second lens, a third lens, and a fourth lens in this order from the object side.