38 results about "Rigid gas permeable lens" patented technology

A corneal-scleral orthokeratology contact lens is formed of rigid gas permeable material with uniform arc lengths in the treatment area even when the corneal curvature varies and asymmetric blends or splines called minor zones, where the portion of the blend or spline is shorter toward the lens center and broader toward the lens edge, and relieve the treatment area of all centering responsibility, transferring it to the limbal-scleral region. The method of determining the total sagittal height of an eye at a given chord diameter to predetermine exact fitting parameters and predict unaided visual outcome trial lenses, with exact chord and sagittal height values used to match the sagittal height of an eye, the sagittal value may be obtained from some ocular topographers. A computer program can easily take the sagittal information and design an optimum lens.

Embodiments of the technology relate to a contact lens having a core that is coated by a hydrogel layer, and to methods of making such a lens. The coated lens can include a rigid gas permeable contact lens. The coated lens can also include a hybrid silicone and rigid gas permeable contact lens. In one aspect, embodiments provide for a coated contact lens comprising a lens core with a water equilibrium constant of less than about 2% comprising an outer surface; and a hydrogel layer covalently attached to at least a portion of the outer surface, the hydrogel layer adapted to contact an ophthalmic surface, wherein the hydrogel layer comprises a hydrophilic polymer population of one or more species.

A rigid gas permeable lens care composition. The composition includes a disinfecting amount of at least one biguanide antimicrobial agent and a straight chain polyether surfactant based upon PEO-PPO-PEO, PPO-PEO-PPO and combinations thereof. In one embodiment, the straight chain polyether surfactant has an HLB value of less than or equal to 15 and an average molecular weight value of between about 5000 and 7000. Preferably, no rubbing is required to disinfect the rigid gas permeable contact lenses is required. Methods of making and using the same are also described.

A shipping container is provided for transporting biologically hazardous materials. The shipping container includes a rigid gas permeable exterior enclosure and an interior positioned substantially gas impermeable flexible bag. Preferably, the exterior enclosure includes an outer cardboard box and inner foam box made of expanded polystyrene. Preferably, the inner bag is made of polyethylene and includes a conventional open top. Preferably, the bag also includes two laterally extending lines. A first line provides a visual indication to the user where air should be evacuated from the bag. A second line is provided to indicate where the bag should be sealed.

An “accommodating contact lens” or “focusable contact lens” is a contact lens comprised of a single unit lens, primarily of a rigid gas permeable material, that has one optical power ground into the lens and is fitted for the eye for clear vision at distance when the eye is in a relaxed, unaccommodated state. Unlike a standard single vision, rigid gas permeable contact lens, it has a modified anterior surface, which exists as either an excavated, concave region or heaped ridge running the entire circular midperipheral to peripheral region of the contact lens, that allows the eyelids a contact point on the lens to re-shape or move the contact lens either by squeezing or lifting it anteriorly from the eye during an attempt to accommodate or focus at near, in order to provide to the eye additional power and clear vision at intermediate or near distances.

A method, computer program product, and data processing system for designing a contact lens. A sagittal image of an anterior portion of an eye having a sclera is measured. Measuring is performed using a digital imaging device. Measuring includes measuring the sclera. A sagittal image is formed. A shape of the eye is derived using the sagittal image, wherein the shape includes the sclera. The shape is converted to a curvature of a contact lens. The curvature is designed such that the contact lens, once manufactured, can be worn over a surface of the eye.

An apparatus for conveying fluidized high temperature finely divided dry material by gravity utilizes a multi-layered, gas permeable gas distributor member comprising (i) an upper layer a flat, rigid gas permeable, porous medium capable of withstanding temperatures up to about 2900° F. through which gas to fluidize the material will pass; (ii) a middle layer comprised of a gas permeable insulation material that maintains its physical integrity when exposed to temperature differentials ranging from about 500° F. to about 2900° F.; and (iii) a lower layer that supports the top and middle layers comprising a substantially flat plate having a plurality of openings therethrough through which fluidizing gas can pass.

A contact lens for wearing on a patient's eye comprises an anterior surface adapted to face away from the eye and a posterior surface adapted to face toward the eye. The posterior surface has an optical zone disposed in the center of the lens, a secondary zone coupled to the optical zone and extending radially therefrom, and a peripheral zone coupled to the secondary zone and extending radially therefrom. The curve of the optical zone is spherical and rearwardly concave, the curve of the secondary zone is aspheric and rearwardly concave, and the curve of the peripheral zone is spherical and rearwardly concave.

A rigid gas permeable lens care composition. The composition includes a disinfecting amount of at least one biguanide antimicrobial agent and a straight chain polyether surfactant based upon PEO-PPO-PEO, PPO-PEO-PPO and combinations thereof. In one embodiment, the straight chain polyether surfactant has an HLB value of less than or equal to 15 and an average molecular weight value of between about 5000 and 7000. Preferably, no rubbing is required to disinfect the rigid gas permeable contact lenses is required. Methods of making and using the same are also described.

A copolymer useful as a rigid gas permeable contact lens material is the polymerization product of a monomeric mixture comprising a polysiloxane-containing urethane or urea prepolymer endcapped with polymerizable ethylenically unsaturated radicals.

The invention relates to an automatic small-sized rigid gas permeable contact lens polishing liquid cleaning apparatus which mainly solves the problems that the existing rigid gas permeable contact lens polishing equipment can not automatically discharge waste liquid, waste liquid settled in an equipment tank is easy to overflow, and clean production environment cannot be maintained easily, and production efficiency is greatly reduced as waste liquid needs to be cleaned frequently during production process. The cleaning apparatus comprises a container, a containing cavity is arranged in the container, an exhaust pipe and a liquid absorption pipe which are communicated with the containing cavity are arranged on the container, an outlet end of the exhaust pipe is communicated with a vacuum opening of a vacuum generator by a connector, an air inlet of the vacuum generator is communicated with a compressed air pipe, and a liquid inlet of the liquid absorption pipe is arranged at the bottom of a waste liquid tank. The apparatus has the advantages of convenience in use, easiness for control and good safety, can timely and fast treat the polishing waste liquid so as to prevent influence of the waste liquid on the production environment, and can effectively improve production efficiency of a rigid gas permeable contact lens through automatic cleaning.