The invention relates to a microscope (100) having a transmitted-light lighting device (10) for critical lighting of an object (O) to be observed, comprising: a light source (20) having an LED assembly having a light-emitting surface, a light-directing unit (30, 30') having a collimator (35, 35') and a reflecting jacket surface (34, 34'), both for orienting light coupled into the light-directing unit (30, 30'), and having an outcoupling surface (32, 32'), wherein the outcoupling surface (32, 32') has an outcoupling surface dimension (D), wherein the light-emitting surface of the light source (20) is smaller than the outcoupling surface (32, 32') of the light-directing unit (30, 30'), wherein the light-directing unit (30, 30') is arranged in such a way that light emitted by the light source (20) is coupled in and is coupled out from the outcoupling surface (32, 32'), a condensor (40) between the outcoupling surface (32, 32') of the light-directing unit (30, 30') and the object (O) to be observed, wherein the condensor has an aperture (41) having an aperture dimension (A) and is arranged in such a way that the aperture (41) is completely irradiated with the light coupled out from the outcoupling surface (32, 32').