An apparatus for observing a sample (1) with a TEM column and an optical high resolution scanning microscope (10). The sample position when observing the sample with the TEM column differs from the sample position when observing the sample with the optical microscope in that in the latter case the sample is tilted towards the light-optical microscope. By using an optical microscope of the scanning type, and preferably using monochromatic light, the lens elements (11) of the optical microscope facing the sample position can be sufficiently small to be positioned between the pole faces (8A, 8B) of the (magnetic) particle-optical objective lens (7). This is in contrast with the objective lens systems conventionally used in optical microscopes, which show a large diameter. Furthermore the optical microscope, or at least the parts (11) close to the sample, may be retractable so as to free space when imaging in TEM mode.