摘要:
The invention provides methods for correcting presbyopia and lenses for such correction in which production of a full range of multifocal lenses is accomplished using three rotationally symmetric, aspheric back surfaces, the design of which base curves is a function of refractive power.
摘要:
The invention provides a contact lens that corrects for the wearer's refractive prescription by taking into account both pupil size and the Stiles Crawford effect of the first order.
摘要:
A method for designing ophthalmic lenses, including progressive addition lenses, and lenses produced by the method are provided. The method permits the direct correlation of an individual's subjective assessment of the lens' performance and the objective measure of lens performance relative to the individual. The method permits generation of lens designs based on the head and eye movement of the individual and the designing of customized lenses.
摘要:
A high spectral purity microwave oscillator is provided. The Oscillator uses an air-dielectric cavity and employs the known carrier-suppression technique. In one embodiment, the oscillator employs a high-Q cavity to self-sustain an oscillating signal formed by feeding back into its input a power-amplified output signal of the cavity in which residual phase noise in the amplifier stages is suppressed. A bandpass filter selects the cavity mode. FIG. 1 illustrates this embodiment. Another embodiment suppresses the noise of a voltage-controlled oscillator whose frequency and power-amplified output interrogates the cavity mode. FIG. 2 illustrates this embodiment.
摘要:
A progressive optic has an optical preform wherein the radius of curvature of the surface is altered by forming discrete spherical portions across the surface. A thin intermediate layer, having a different refractive index from the optical preform, is then cast over the formed optical preform surface. The optical preform having the thin intermediate layer is then cast with a resin superstrate layer which restores the curve of the optic. Each spherical section, defined by the spherical portions and corresponding portions of the outer surface of the superstrate layer, alters the spherical power of the adjacent spherical section by about 0.03 D to 0.05 D.
摘要:
A method for providing a contact lens for a patient. According to this method, an optical preform is selected, and a resting position of the optical preform on the patient's eye is determined. An optical feature is also located on a patient's eye. Then, a reference position is located on the surface of the optical preform coincident with the optical feature on the patients eye, when the optical preform is in the resting position. Finally, the optical modification is provided on the optical preform at a location based on the reference position on the optical preform, either by machining the preform itself or by machining a mold that is subsequently used to form the lens.
摘要:
Prismatic intraocular lenses are disclosed for restoring visual function to an eye having macular degeneration. The lenses each include a convex lens optic for receiving and focusing light rays, a prismatic wedge located posterior to the convex lens optic for receiving and directing light rays to a first portion of a retina of the eye, and means for in situ alteration of the optical characteristics of the intraocular lens to direct light rays to a second functional portion of the retina.
摘要:
Microspheres are produced by cobalt gamma radiation initiated polymerization of a dilute aqueous vinyl pyridine solution. Addition of cross-linking agent provides higher surface area beads. Addition of monomers such as hydroxyethylmethacrylate acrylamide or methacrylamide increases hydrophilic properties and surface area of the beads. High surface area catalytic supports are formed in the presence of controlled pore glass substrate.
摘要:
Microspheres are produced by cobalt gamma radiation initiated polymerization of a dilute aqueous vinyl pyridine solution. Addition of cross-linking agent provides higher surface area beads. Addition of monomers such as hydroxyethylmethacrylate acrylamide or methacrylamide increases hydrophilic properties and surface area of the beads. High surface area catalytic supports are formed in the presence of controlled pore glass substrate.