Abstract:
A marking apparatus for providing desired marks such as characters, symbols, graphics, etc. on surfaces of contact lenses in a standardized manner. The marking apparatus includes a main shaft rotatable about an axis and a screen support mounted on the main shaft so as to be rotated therewith. The screen support has a plurality of marking holes provided at equal intervals around a circumference thereof and a screen is stretched across the support. The screen includes patterns associated with the desired mark which are provided in correspondence with the marking holes. A bracket is mounted on the main shaft under the screen support so as to be rotated with the main shaft. A plurality of supporters are supported by the bracket and function to individually support lens beds on which the lenses are respectively disposed. The supporters are movable up and down between a position where the respective contact lenses mounted on the lens beds are brought into contact with corresponding patterns of the screen and a displaced position where the contact lenses can be mounted on or removed from the supporters. Finally, an injector placed above the screen support applies a print solution to the screen stretched in the corresponding one of the marking holes of the screen support.
Abstract:
A multifocal ocular lens having a vision correction area which consists of a central, an intermediate, and an outer vision correction region having respective different values of an optical power, and which has an optical axis with which centers of the central and outer vision correction regions are aligned, the central and outer vision correction regions having respectively determined first and second mutually different values of the optical power, wherein the optical power of the intermediate region is represented by a combination of a first and a second quadratic curve connected to each other at a point of inflection which corresponds to a radial position of a boundary between the inner and outer sections, and which corresponds to a desired third value of the optical power between the first and second values, or the optical power of the intermediate region is represented by one polynomial equation whose degree is not smaller than 2 and continuously changes from the first value to the second value with an increase in a radial distance from the optical axis.
Abstract:
The inner and outer surfaces of a toric contact lens have respectively a curved surface having a different radius of curvature wherein the central axis of the outer surface is deviated downwardly from the central axis of the inner surface. Accordingly, the position of the gravity center of the lens is lowered because the lower portion of the lens is thicker than the upper portion. Further, slab-off portions are formed in the upper and lower portions of the outer surface of the lens. The contact lens of the present invention can prevent the rotation of the lens on the cornea, provides a good feeling to a wearer, and is safe in use.
Abstract:
A contact lens wherein a dioptric power P is held within a range of −10-0 diopters, a back junction is located outward of a front junction in a diametric direction orthogonal to a center axis of the lens, a central lens thickness TC measures 0.03-0.50 mm along the center axis, a front junction lens thickness TFJ measures 0.05 mm or more, and a back-junction lens thickness TBJ is determined depending upon said dioptric power P so as to satisfy a following expression: &Sgr;(Ai·10−i·Pi)≦TBJ/TFJ≦&Sgr;(Bi·10−i·Pi) where, A0=+1.2382 A1=−0.1741 A2=−1.4711 A3=−0.9355 B0=+1.4699 B1=−0.2523 B2=−1.9897 B3=−1.2603.
Abstract:
A multifocal ocular lens having a vision correction area including at least one distant vision correction region having a first optical power value for distant vision correction and at least one near vision correction region having a second optical power value for near vision correction, wherein the vision correction area further includes a central intermediate-distance vision correction region which has a third optical power value for intermediate vision correction between the first and second optical power values and which is located in a central portion of the vision correction area such that the distant and near vision correction regions are located radially outwardly of the central intermediate-distance vision correction region.
Abstract:
Presbyopia correction contact lens including an optical zone consisting of a substantially circular central optical portion and an annular peripheral optical portion outside the central optical portion, the central and peripheral optical portions having respective different optical power values, so that the central and peripheral optical portions provide one and the other of a near vision correction region and a distant vision correction region, respectively, wherein the central and peripheral optical portions provide the near and distant vision correction regions, respectively, and the optical zone includes a front surface having an arcuate configuration with a substantially constant curvature in cross section taken in a plane parallel to a diametric direction of the contact lens, and a back surface consisting of a central portion corresponding to the central optical portion and a peripheral portion corresponding to the peripheral optical portion, the central portion of the back surface having an arcuate configuration with a substantially constant curvature in cross section taken in said plane, which curvature is different from that of the peripheral portion of the back surface.
Abstract:
Disclosed is a contact lens having a back surface to be placed on a cornea. The back surface includes a generally circular central zone whose radius of curvature gradually decrease from its center toward its periphery, and an peripheral zone disposed around the central zone.
Abstract:
Disclosed is a contact lens including an optical zone having a substantially circular shape; an peripheral zone having an annular shape and located around the optical zone; and an intermediate zone having an annular shape and located between the optical and peripheral zones. The intermediate zone including a convex portion formed in at least one radial position of a back surface thereof so as to extend in a circumferential direction thereof with an outwardly curved surface as seen in a diametrical cross-section of the lens.
Abstract:
Multifocal ocular lens including a central vision correction region having a first optical power value, an outer vision correction region spaced radially outwardly from the central vision correction region and having a second optical power value different from the first optical power value, and an intermediate vision correction region located radially intermediate between the central and outer vision correction regions and having a distribution of optical power between the first and second optical power values, and wherein the intermediate region has a first transition point and a second transition point which is not radially inwardly spaced from the first transition point, such that the distribution of the optical power of the intermediate region includes two optical power values which are defined by the first and second transition points, respectively, and which are determined such that the optical power value defined by the second transition point is closer to the first optical power value of the central region than the optical power value defined by the first transition point.
Abstract:
A multifocal ocular lens having a vision correction area which includes a central and outer vision correction region, an intermediate region located between the central and outer regions, and an intermediate-distance vision correction region located radially outwardly of and adjacent to the outer region, and which has an optical axis with which centers of these regions are aligned, the central and outer vision correction regions having respective different first and second optical power values, wherein the optical power of the intermediate region located between the central and outer regions is represented by a combination of two different quadratic curves connected to each other at a point of inflection which corresponds to a desired third optical power between the first and second values, and wherein the intermediate-distance vision correction region located radially outwardly of the outer region includes radially inner and outer varying-power zones, the optical power in the radially inner varying-power zone continuously varying from the second value of the outer vision correction region to a predetermined fourth value which is between the first and second values, while the optical power in the radially outer varying-power zone continuously varying from the fourth value to the second value of the outer region.