Process for the reciprocal positioning of pairs of opposing shaping tool parts and shaping tool for the production of precision parts particularly of contact lenses

摘要

Proposed is a shaping tool for manufacturing precision-made articles, in particular contact lenses, said shaping tool comprising two halves fitted with inserts (18, 38) and with a cavity (50) between them. The tool is made of ceramic glass with negligible thermal expansion in a given work range. On each side of the cavity (50) is a ceramic-glass insert which defines the shape of the part being manufactured and which is positively held round its circumference in a positioning plate (16, 36) also made of ceramic glass. The positioning plates (16, 36) are each mounted on a ceramic-glass mounting plate (14, 34).