A method utilizes a dynamically controllable optical element that receives an electrical field, which changes an index of refraction in at least one direction within the optical element. The change in index of refraction imparts a change to a beam of radiation passing through the optical element. The electric field is controlled by a feedback/control signal from a feedback system that includes a detector positioned proximate an image plane in the system. The optical element can be positioned in various places within the system depending on what light characteristics need to be adjusted, for example after an illumination system or after a light patterning system. In this manner, the optical element, under control of the dynamic electric field, can dynamically change its propagation characteristics to dynamically change either a beam of illumination from the illumination system or a patterned beam of radiation from the patterning system, such that they exhibit desired light characteristics.