Patent ID: 8724086

Claim:
An apparatus, comprising: illumination optics configured to illuminate object field points of an object field in an object plane; and projection optics configured to image the object field of the illumination optics on an image field in an image plane, wherein: the illumination optics have, for each object field point of the object field, an exit pupil associated with the object point, wherein sin(γ) is a greatest marginal angle value of the exit pupil; the illumination optics comprise a multi-mirror array comprising a plurality of mirrors configured to adjust an intensity distribution in exit pupils associated to the object field points; the illumination optics comprise an optical system configured to temporally stabilise the illumination of the multi-mirror array so that, for each object field point, a first adjusted intensity distribution in the associated exit pupil deviates from a second adjusted intensity distribution in the associated exit pupil by less than 0.1 in at least one parameter selected from the group consisting of an inner σ and an outer σ; during use, an illumination ray bundle of illumination rays traverses between a light source and the multi-mirror array, the optical system is configured to temporal stabilise the illumination of the multi-mirror array by superposing the illumination rays of the illumination ray bundle on the multi-mirror array, the optical system is configured for spatially homogeneous illumination of the multi-mirror array, and the apparatus is a projection exposure apparatus configured to be used in microlithography.