Claims _](vt,|L  
1. A method of measuring centration of a lens, the method comprising: ?9_<LE q  
placing the lens on a platen, wherein the lens comprises a first major surface and a second major surface, wherein the first major surface is rotationally symmetrical about a first axis, and further wherein the first major surface comprises a first lens centration mark located at the intersection of the first major surface and the first axis, wherein placing the lens on the platen comprises placing the lens on the platen such that the first lens centration mark is aligned with a rotation axis of the platen; -DrR6kGjR  
leveling the lens relative to a plane of rotation that is orthogonal to the rotation axis of the platen; ]&1Kz 2/  
rotating the lens about the rotation axis of the platen; and