摘要 |
<p>CONTACT LENS CONSTRUCTION Various forms of multifocal contact lenses can be produced having improved properties. The surface of a lens (1) to be polished is brought into contact with a polishing compound (19) associated with a flexible (but non-resilient) sheet (18), causing the sheet (18) to flex. Fluid pressure is applied to the sheet counteracting the flexing as a result of lens contact, so that polishing compound associated with the sheet makes contact with the lens surface with uniform force distribution. Relative rotation between the lens (1) and sheet (18) is effected so that all portions of the lens surface in contact with the polishing compound are polished to the same extent. The lens is then ground to provide a multifocal lens. A hydrophilic or silicone multifocal contact lens having desired distance and intermediate powers may be constructed by acting on the lens (2) so that it is capable of accepting grinding activity, and the grinding it without distorting it. The lens (2) may be backed by a chuck (34) or hard lens (3), or frozen, and ground by grinding apparatus (60) while backed or frozen.</p> |