US Patent 7732110 Method for exposing a substrate and lithographic projection apparatus

A method for exposing a resist layer on a substrate to an image of a pattern on a mask is disclosed whereby, after starting exposure and before completing exposure, a controlled amount of contrast loss is introduced by a controller in the image at the resist layer by changing during exposure the position of the substrate holder. The contrast loss affects the pitch dependency of the resolution of a lithographic projection apparatus, and its control is used to match pitch dependency of resolution between different lithographic projection apparatus.