Polishing device for polishing concave lens faces of optical lenses, and method for operation thereof

A method for operating a polishing device (1) comprising:

• a workpiece holder (10) for receiving an optical lens (100) and having a polishing tool (20),
• the polishing tool (20) having a support element (21) with a curved polishing surface (23), being driven in a rotating manner about a rotation axis (R),
• either the curved lens face (101) being concave and the curved polishing surface (23) being convex, or the curved lens face (101) being convex and the curved polishing surface (23) being concave,
• the workpiece holder (10) being driven in a rotating manner about a first axis (A1), in order to rotate the optical lens (100),
• a distance (z) between the workpiece holder (10) and the polishing tool (20) being adjustable along a second axis (A2),
• an offset (x) between the workpiece holder (10) and the polishing device (20) being adjustable along a third axis (A3), which is aligned transversely in relation to the first axis (A1),
• wherein
• the curved polishing surface (23) is located on an elastic substructure (22) of the polishing tool (20),
• a pitch angle (W) between the rotation axis (R) and the first axis (A1) is adjustable by tilting about a fourth axis (A4),
• when there is an optical lens (100) received in the workpiece holder (10), the polishing tool (20) can be placed, according to the pitch angle (W), obliquely on the curved lens face (101), and a strip-type contact area (F) can be realized between the polishing surface (23) and the curved lens face (101) as a result of deformation of the elastic substructure (22), and
• the pitch angle (W) between the rotation axis (R) and the first axis (A1) being such a magnitude that the polishing surface (23) is partially raised from the curved lens face (101) and a portion of the polishing surface (23) floats above the lens face (101) at a lateral distance from the contact area,
• the method comprising the following steps:
• a) receiving an optical lens (100) with the workpiece holder (10),
• b) placing the polishing tool (20), with the polishing surface (23), on the curved lens face (101),
• c) rotating the polishing tool (20) about the rotation axis (R),
• d) performing a polishing operation, by driving in an interpolating manner
• the speed of rotation of the workpiece holder (10) about the first axis (A1),
• the distance (z) between the workpiece holder (10) and the polishing tool (20) along the second axis (A2),
• the offset (x) between the workpiece holder (10) and the polishing tool (20) along the third axis (A3), and
• the pitch angle (W) between the rotation axis (R) and the first axis (A1), by tilting about the fourth axis (A4),
• wherein the polishing tool (20) is placed, according to the pitch angle (W), obliquely on the curved lens face (101), and a strip-type contact area (F) is realized between the polishing surface (23) and the curved lens face (101) as a result of deformation of the elastic substrate (22), and
• the pitch angle (2) between the rotation axis (R) and the first axis (A1) being of such a magnitude that the polishing surface (23) is partially raised from the curved lens face (101) and a portion of the polishing surface (23) floats above the lens face (101) at a lateral distance from the contact area.