Patent ID: 6965484
Filing Date: 2005-11-15
Classification: G03F

Abstract:
1. An imaging system comprising: a light source to generate light for illuminating an object having features aligned in a first direction and features aligned in a second direction; a lens for imaging the illuminated object onto a surface; a spatial selection device selective in a first mode of light corresponding to features of the illuminated object aligned in the first direction and selective in a second mode of light corresponding to features of the illuminated object aligned in the second direction, wherein the spatial selection device comprises a pupil filter and a rotation device for rotating the pupil filter with respect to an optical axis, wherein the rotation device is configured for rotating the pupil filter between first and second positions in the first and second modes, respectively, wherein the pupil filter includes one or more blocking regions and one or more non-blocking regions, and wherein the blocking regions comprise wedge-shaped blocking regions; a polarization device optically coupled to the spatial selection device and selective in the first mode of s-polarized light corresponding to the first direction and selective in the second mode of s-polarized light corresponding to the second direction; and a controller for selecting operation in the first mode or in the second mode.