In a method for correcting optical proximity effects (Optical Proximity Correction, OPC) when imaging a pattern, arranged in the object surface of a projection objective, into the image surface of the projection objective with the aid of a projection objective, a multiplicity of optical elements and at least one pupil surface that is Fourier-transformed to the image surface are arranged between the object surface and the image surface. An optical filtering of the light used for the imaging is carried out with the aid of at least one OPC filter inserted between the object surface and the image surface in accordance with an OPC filter function that is adapted to the pattern and corresponds to a spatially dependent transmission filtering in the region of the pupil surface of the imaging system. The profile of the pupil transmission function is adapted with the aid of the OPC filter to the pattern, characterized by the position of diffraction orders, of the mask such that there is respectively present for all the diffraction orders contributing to the imaging an optimized pupil transmission which leads to a minimization of line width variations, dependent on line density, in the image surface.