Patent ID: 7413502

Claim:
A method for producing shaped bodies having optically active surfaces according to a general or individual prescription, including the use of plastic blanks in the form of flat, round discs of any surface geometry and including the application of manufacturing techniques with mechanical material removal, characterised in that each plastic blanks ( 1 ) used is clamped at an outer edge and a final surface geometry and surface quality of a convex front face ( 19 ) and a concave rear face ( 27 ) of the shaped body is produced by machining, smoothing and optionally polishing, the shaped body part of a workpiece 16 with an annular region ( 30 ) of larger thickness ( 33 ) being retained at an outer circumference of the workpiece ( 16 ), the annular region ( 30 ) serving to clamp or to handle the workpiece ( 16 ) during all processing and transport operations, and also with the annular region ( 30 ) supporting and mechanically stabilising the shaped body ( 32 ) for further processing, in that one or both of markings and shapes are applied to the annular region ( 30 ) which serve for the identification of the processing axes, and in that very fine markings are applied to the surface of the shaped body ( 32 ) which serve to characterise an axial position of the surface geometries produced, and that subsequently the shaped body ( 32 ) is separated from the annular region ( 30 ).