It is well known that in the case of very high precise reproducing of sharp-edged two- dimensional objects by imaging there are several and especially nonlinear influences. This is important in cases of fotolithography and of high-precision measurement of edge position. in this case there are high contrast objects like masks which leads to an essentially nonlinear interaction of diffraction, interference, and illumination in image generation. For this reason there is a nonlinear influence of wavefront distortion (aberrations of the imaging system) on image intensity distribution. /1/,/2/. Because of this reasons and the fact, that the design and adjustment /3/,/4/ of high performance optical systems has to take into account also very small residual aberrations, the question of optimum aberration balancing for edge imaging is worth to be considered in more detail.
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