SEGMENTAL MULTIFOCAL CONTACT LENS AND METHOD OF ITS MANUFACTURE VARIANTS Russian patent published in 1997 - IPC

FIELD: optical engineering. SUBSTANCE: lens consists of multiple segments. Alternating segments have different optical refraction power. At least one segment is intended for far-sighted vision and the other, for near-sighted vision. Lens does not require orientation for formation of adequate farsighted and near-sighted vision and normal stereoscopic effect.. One or both segments having the optical refraction power may have aspherical surface of lens. Preferably lens has at least one aspherical surface, and segments are separated by arc-shaped trajectory directed from lens center to its edge. Such lens is manufactured with the aid of shaping moulds and by cutting of shaping moulds from edge through center up to opposite edge along preset trajectory. Shaping moulds are cut so that segments formed are interchangeable and may be assembled together for obtaining the shaping mould which can shape multifocal refraction contact lens. EFFECT: more effective shaping process. 20 cl, 9 dwg