Abstract: A universal folding condenser (1) with a support plate (4), which is fastened on the microscope and has an arm (4') angled off through 90.degree., is described. Arranged in the support plate (4) is a fixed lens (5). Above the support plate (4) there is provided a first, rectangularly shaped swivel arm (7) with a condenser head and a lens element (2) for optional introduction into the path of the illuminating beam (11). Arranged underneath the support (4) is a second, rectangularly shaped swivel arm (8) with a second lens element (3). The two swivel arms (7, 8) are forcibly coupled by means of a shifting linkage (6) in such a way that, for objectives with low magnification, the two lens elements (2, 3) are introduced into the path of the illuminating beam (11) and, for objectives with high magnification, only the condenser head is introduced into the path of the illuminating beam (11).