Patent ID: 7876420
Filing Date: 2011-01-25
Classification: G03F

Abstract:
1. A system, comprising: an illumination system that is constructed and arranged to produce a patterned beam of radiation in accordance with a patterning device; a projection system that is constructed and arranged to project the patterned beam of radiation onto a target portion of an object at an image plane; a feedback system that is constructed and arranged to detect at least a part of the projected patterned beam at the image plane and generate a control signal therefrom; a dynamically controllable optical element having an index of refraction in at least one direction controllable by an electric field, wherein an index of refraction of two or more portions of the optical element can be selectively and individually controlled by varying an applied electrical field across each portion of the two or more portions of the optical element, wherein at least two portions of the two or more portions of the optical element are placed adjacent to each other such that one portion being rotated with respect to the other portion to control beam divergence in two directions; and a generator that is constructed and arranged to generate the applied electrical field across the each portion of the at least two portions of the optical element based on the control signal generated by the feedback system.