A method of making a rotational optical arrangement and the arrangement made
by
the method, wherein the method includes providing a rotatable unit. The unit has
a surface extending transverse to a center axis of the unit and at a predefined
angle to an interface normal direction, and the unit having a pattern with at least
two portions that each have a different optical characteristic. A mechanism is
provided for rotating the unit around a mechanism-induced rotational axis. The
center axis of the unit is separately aligned to the mechanism-induced rotational
axis for radial offset correction. The interface normal direction is separately
aligning to the mechanism-induced rotational axis for skew correction.