Method of beveling an ophthalmic lens blank, machine programmed therefor, and computer program

A machine programmed to edge a lens blank, comprising:

• an edger device for forming a bevel in a peripheral edge of a lens blank;
• a central processing unit operably associated with the edger device for controlling operation of the edger device;
• and
• a computer program stored on a medium in communication with said central processing unit, said computer program comprising:
• a) a first instruction set operably causing said edger device to form a bevel in a peripheral edge of a lens blank, the peripheral edge having a portion lying on a first plane and the bevel having an apex extending outwardly from the first plane;
• and
• b) a second instruction set operably causing said edger device to form a step in the peripheral edge intermediate the apex and an interface between the peripheral edge and a major surface of the lens blank, the step having a base lying on a second plane spaced from and parallel to the first plane.

A computer program stored on a medium for use in an edging process employing a lens blank and an edger device, the computer program comprising:

• a first set of computer instructions operably recalling trace data about a lens blank to be processed, the lens blank having first and second opposite major surfaces and a peripheral edge therebetween;
• a second set of computer instructions operably causing an edger device to form a bevel in the peripheral edge of the lens blank at a selected position defined by and relative to the trace data, the peripheral edge having a portion lying on a first plane and the bevel having an apex extending outwardly from the first plane;
• and
• a third set of computer instructions operably causing the edger device to form a step in the peripheral edge intermediate the apex and an interface between the peripheral edge and the second major surface, the step having a base lying on a second plane spaced from and parallel to the first plane.