Patent ID: 6801357
Filing Date: 2004-10-05
Classification: G02B,G03F

Abstract:
A high numerical aperture, broad spectral region catadioptric optical system comprising:a focusing lens group including a plurality of lens elements, with lens surfaces thereof positioned and having curvatures selected to focus ultraviolet light at an intermediate image within the system; a field lens group aligned proximate to said intermediate image, with lens surfaces disposed at second predetermined positions and having curvatures selected to provide substantial correction of chromatic aberrations over a wavelength band including at least one wavelength in the UV range; a catadioptric relay group comprising a plurality of lens surfaces disposed at third predetermined positions and having curvatures selected to form a real image of said intermediate image, such that, in combination with said focusing lens group, primary longitudinal color of the system is substantially corrected over said wavelength band; and a zooming tube lens group comprising multiple lenses formed to zoom or change magnification without changing its higher-order chromatic aberrations, and with lens surfaces thereof disposed at fourth predetermined positions.