Patent ID: 7947412

Claim:
A system comprising: an illuminator that includes a source capable of producing light having a first wavelength; and a mask that includes at least one partly opaque area and a first open area and a second open area within the partly opaque area, each of the first and second open areas is unresolvable by the light and each of the first and second open areas includes features that are smaller than can be resolved by the light having the first wavelength, wherein when the light is produced by the source, a first portion of the light passing through the partly opaque area in the mask is directed onto a target, and a second portion of light passing through the first open area and the second area is redirected by at least one of the features in the first open area and the second area of the mask, the features include slanted lines and spaces in each of the first and second open areas, wherein the lines are non-intersecting each other, and wherein none of portions of the at least one partly opaque area is between two of the features.