An offset number setting device that freely and easily sets an offset number for a tool to be mounted on a tool holder of a turret surface. A display linkage unit displays a turret surface selection screen on a display, displays a tool holder selection screen on the display by selecting the turret surface, and displays an offset number setting screen on the display by selecting the tool holder. An offset number is therefore set for the tool along with the selection of the turret surface on which the tool is mounted.

The disclosure provides a method for manufacturing an ophthalmic device, comprising machining to provide a predetermined surface on a part and which corresponds to an initial ophthalmic surface, the machining comprising: selecting (130) a machining tool having a cutting edge; selecting (140) the initial ophthalmic surface of the ophthalmic device intended to be manufactured; providing (150) a determined kinematics of the machining tool which is function of the initial ophthalmic surface and of a wear parameter of the cutting edge; machining (160) the predetermined surface according to the determined kinematics of the machining tool; wherein the wear parameter is function of at least a distance travelled by the cutting edge for machining the predetermined surface and/or a friction time between the cutting edge and the part which is machined.