Preformed ophthalmic lens base block with textured surface

摘要

The present invention provides novel preformed base blocks that may be used with thermoplastic ophthalmic lens blocking compositions. The preformed base block has a rear portion that is sized and adapted to fit the chuck of a lens processing machine and a front portion that has a textured front surface and preferably a negatively tapered peripheral edge. The front portion is adapted to mechanically retain the thermoplastic blocking composition to form a lens block against a lens blank.