Abstract: Aspheric toric lens designs are disclosed which reduce the number of cylindrical axis locations required for stock keeping units in inventory by aspherizing the toric surface thereof. The present invention pertains to ophthalmic lenses, and in particular to contact lenses such as soft hydrogel contact lenses, particularly designed to fit astigmatic patients who are either non-presbyopic or presbyopic. One of the front and back surfaces of the aspheric toric lens defines a spherical surface corresponding at least to the patient's basic distance prescription Rx. The other of the front and back surfaces defines an aspheric toric curve, wherein the toric surface is constructed with aspheric radii, such that the aspheric curve desensitizes axial misalignment of the toric curve by providing an enhanced depth-of-focus.

Abstract: Concentric aspheric multifocal lens designs are disclosed which use a combination of an aspheric front surface, which results in aberration reduction and contrast vision enhancement, along with a concentric multifocal back surface, to produce a lens design which affords clear vision at a distance and also near without a loss in contrast which is generally typical of prior art simultaneous vision, concentric multifocal lens designs. The aspheric surface improves the modulation transfer function (MTF) of the lens eye combination which improves the focus and contrast of both distance and near images. The design form is valid for contact lenses and intraocular lenses.

Abstract: An apparatus for molding polystyrene mold halves which are used, for subsequent molding of a soft contact lens. The apparatus is designed with superior heat conduction capacity so as to minimize the molding cycle time, while simultaneously producing uniformly precise and accurate optical quality surfaces. Molten polystyrene is provided via a hot runner system to a plurality of mold cavities. In a specific variation, the convex surface provides the optical quality surface to the concave surface of the mold half produced thereby. The structural element which defines the convex surface includes a hollow cylindrical bushing and a removable power insert mounted therein, which may be changed so that the prescription strength of the contact lens to be formed by the mold may be varied. In a first embodiment, the power insert includes only a convex surface at its operational end.

Abstract: Concentric ring, single vision lens designs are disclosed which improve the depth-of-focus of the lens relative to current spherical contact lenses or intraocular lenses by placing at least one additional peripheral optical radius on the front or back surface of the lens. A plurality of concentric annular rings are provided in the periphery of the optic zone of the lens. The arrangement of optic powers in the concentric annular rings includes a mixture of the basic spherical refractive power and other annular rings with less plus or greater minus spherical refractive power, arranged to mediate spherical aberrations and improve visual acuity. The concentric annular ring design corrects peripheral, aperture-dependent ocular aberrations in a discrete, zonal fashion.

Abstract: A multifocus, concentric annular ring lens wherein one of the front and back surfaces of the lens defines a central area comprising a circular disc having a spherical surface corresponding to a basic prescription Rx spherical distance optical power. A plurality of annular rings surround the central area and have alternating spherical near and distance optical powers, and at least one intermediate optical power annular ring. The immediate optical power annular ring is located in the middle or outer region of the lens optic zone, and its optical power is intermediate to the distance and near optical powers, to provide visual acuity at intermediate distances. The intermediate optical power annular ring can be placed anywhere in the middle or outer region of the lens optic zone, and can be the second annular ring from the outer edge of the lens optic zone, or can be the outermost annular ring which defines the outer circumference of the lens optic zone.

Abstract: Concentric annular ring lens designs are disclosed for astigmatic patients, particularly lens designs which reduce the sensitivity of the patient to toric axis misalignment, thus reducing the required number of stock keeping units in inventory for a toric product. Several of the concentric annular ring lens designs comprise a multifocal concentric annular ring design on either the front or back surface and a toric curve on the reverse surface to correct for astigmatism.

Abstract: Non-ballasted, eyelid rotationally stabilized designs are disclosed for use in toric or multifocal toric contact lenses. The back surface of the lens includes a toric or multifocal toric surface and also thin top and bottom zones (slab offs) to achieve eyelid rotational orientation and stabilization. The advantage of this technical approach is in mold manufacturing, wherein the design allows the use of any chosen power spherical stock front mold.

Abstract: A pair of ophthalmic lenses both containing at least two optical powers, one for near vision and one for distance vision are described, both containing in the center portion of the lens the distance optical power. In the preferred embodiment, the remainder of the lens is comprised of annular portions made up of one or more optical zones to provide the desired combined, cumulative ratio of near and distance focal length areas at each pupil diameter. The distance portion located in the center is appropriately suited to the real world situation of requiring distance vision under high illumination situations.

Abstract: Polypropylene surgical monofilaments sutures of improved compliance are made by drawing polypropylene monofilament to a greater extent than its natural draw ratio, followed by annealing with shrinkage.

Abstract: Provided is a process for forming and modifying a self-crimping polyester yarn comprising a plurality of polyester filaments having thick and thin regions along their lengths which are out of phase from filament to filament. The plurality of filaments are produced by first forming a plurality of combined streams of molten melt spun polyester by combining at least first and second extruded molten streams of fiber forming polyester travelling at different extrusion speeds to thereby form thick and thin regions in the combined streams out of phase from other combined streams. The combined streams are then quenched and thereby transformed into solid filaments in a solidification zone provided with a gaseous atmosphere at a temperature below the glass transition temperature of the polyester.

Abstract: Sterile surgical monofilament sutures are disclosed. The sutures are made from ethylene-propylene copolymers, and have improved compliance, compared with polypropylene homopolymer sutures.