In a magnetic lens arrangement for use in corpuscular radiation equipment working under a vacuum, said lens arrangement including a vacuum chamber to receive an object to be examined and at least one current-carrying lens coil winding which is enclosed by a superconductive shielding device and is disposed around two superconductive, hollow cylindrical shielding parts disposed coaxial to the beam guidance axis for the lens arrangement, the shielding parts being spaced one behind the other as viewed in the beam guidance direction with a gap of predetermined gap width formed between their adjacent faces, the improvement comprising, the shielding device being of cup shaped design and the vacuum chamber to receive the object to be examined being located in front of the open side of the cup shaped shielding device, and of the face of the first shielding part facing away from the gap, as viewed in the beam direction, said vacuum chamber being maintained at a temperature which is approximately room temperature.