A family of microscopes with illumination systems directing a sheet of light having an approximately planar extension in an illumination axis of an illumination beam path and in a transverse axis orthogonally oriented to the illumination axis. The microscopes have detection devices used to detect light that is emitted by a sample region. The detection devices including a detection lens system disposed in the detection beam path and an optical detection element spaced from a front lens of the detection lens system and independently adjustable thereof. The optical detection element continuously varies the size of a detection image field and/or continuously displaces a focal plane of detection in the P-region.