Abstract: A process for forming a preform for use in compression molding an optical lens is provided. A heated reservoir desirably a thermoplastic extruder is filled with a thermoplastic material. The heated reservoir has a fluid outlet which is located in close proximity to the concave mold. The thermoplastic material, for example, polycarbonate pellets is fluidized in the heated reservoir. A predetermined amount of a fluid thermoplastic material is dispensed from the reservoir outlet onto the outside the edge of a heated concave mold prior to the fluid solidifying so that the fluid makes point or line contact as it first contacts the concave molds. The fluid flows down the sloping wall of the concave mold into the concave mold and forms a blob of material having a greater thickness at the center of the concave mold than at the periphery of the mold. The thermoplastic blob is then allowed to cool below its melting temperature.

Abstract: A method for forming a thermoplastic preform into a lens by compression molding between a pair of molds is provided. In another aspect of the invention a set of novel preforms made from a thermoplastic material is provided. The preforms have different radii of curvature. Preferably each different curvature preform comes in different weights desirably two or three different weights. A series of mating concave and convex mold halves are provided for use with the preforms. According to the invention a limited number of concave mold halves are provided. A wide range of single vision and multifocal lenses can be supplied from three (3) to six (6) base curve concave molds halves having different radii of curvatures. According to the invention a first concave mold half with a radius of curvature of less than two (2) diopters is provided. Each successive concave mold half has a radius of curvature of from one (1) to three (3) diopters greater than the previous mold half in the series.

Abstract: A compression process for fabricating a substantially finished coated/layered lens for eyeglasses with a thermoplastic lens preform, with the lens having surfaces for correcting vision. The process comprised suitably placing on at least one of a pair of molds with molding surfaces conforming to the surfaces of the finished lens a thermoplastic film-layer/coating or multiple layers or coatings, each having a given thickness and predetermined characteristics and/or properties desired in the finished lens. The lens preform is then placed on the thermoplastic film-layer/coating; and heating and molding in situ of the film-layer/coating with the lens preform is then conducted while the lens preform is under compressive forces of the compression process until a generally predetermined lens thickness is achieved.

Abstract: A method of manufacturing a prescription lens, for eyeglasses on site by compression molding, in a pair of upper and lower molds having a mold surfaces from a thermoplastic preformed lens blank having opposite surfaces and a periphery, comprising the steps of: preheating a preform blank at a first temperature and preheating the upper and lower molds to a second higher temperature; positioning the preheated preform between the upper and lower preheated molds such that the preform makes a single point or line contact with each of the mold surfaces; initially compressing the preformed at a first fixed rate of speed regardless of pressure exerted on the preform, with the preform being compressed to about 4 mm of a predetermined lens thickness desired for the prescription lens; finally compressing the preform to a substantially finished prescription lens at a second fixed rate of speed substantially higher than the first fixed rate of speed regardless of pressure exerted on the preform while substantially maintain

Abstract: An apparatus, for making a lens from thermoplastic material in the form of a monolithic preform mass, having a press; and a pair of lens molds positioned in said press. The monolithic preform mass has at least one or more radii and is disposed between the lens molds such that said one or more radii make point or line contact with said lens molds. Means are provided for closing the pair of lens molds, and pressing the molds toward each other and against said preform mass to a predetermined pressure; and for heating up the molds until the preform mass begins to soften with the predetermined pressure varying slightly therefrom.

Abstract: A method for forming a preform mass of thermoplastic material into a lens by compression molding between a pair of molds without the formation of air bubbles or the entrapment of air pockets in the finished lens by preheating the preform mass and molds, and further continuing to apply increased pressure while increasing the temperature or maintaining a predetermined temperature and pressure until the mass has been compressed between the two molds into the shape of a substantially finished lens.

Abstract: A method for forming a preform mass of thermoplastic material into a lens without the formation of air bubbles or the entrapment of air pockets in the finished lens includes softening the preform mass under a predetermined pressure and temperature and continuing to apply the predetermined pressure while increasing the temperature until the mass has been compressed between two molds into the shape of the lens.

Abstract: Apparatus is provided for fabricating ophthalmic lenses of the single vision and bifocal type comprising a holder having a base portion for support thereof. An outer circumferential side wall extends upwardly from the base portion and terminates in an upper surface which is disposed in substantially parallel relationship of the bottom surface of the holder base portion. The side walls comprise a plurality of equally spaced support posts. The support posts are provided with a lower step and an upper step with the upper step being disposed radially outwardly of said lower step. The lower steps define a parallel support surface upon which there is disposed a lower mold. The upper steps define a parallel support surface upon which is disposed an upper mold. The upper and lower support surfaces being disposed in substantially parallel relationship.

Abstract: A bifocal lens is produced on either a previously formed blank lens, or completely in a singular casting between two molds. The bifocular lens is obtained by supporting a bifocal lower mold having a recessed bifocal well area on itsconcave surface and filling the lower mold with a resin material. By positioning an upper mold in vertically spaced relationship to the lower mold, the resin material is displaced to extend between the overlapping surfaces of the molds to form the configuration of the bifocal lens with a bifocular portion on the convex lens surface corresponding to the bifocal well on the lower mold. Curing of the resin material situated between the molds and cooling the resin material and the molds forms the complete lens. Thereafter a separating of the bifocal lens from between the molds leaves the bifocal lens in a position to be completed and installed in a pair of eye glasses. Single vision ophthalmic lenses are similarly produced by means of the aforedescribed method.