A new high voltage (350 kV) universal electron microscope and its applications
A research electron microscope with an accelerating voltage up to 350 kV was developed. High tension is generated by means of step-up transformers, and fed to the three-stage accelerators through a coaxial cable which avoids exposing the highest tension. Thus the corona and leakage loss are minimized and the fluctuation of voltage is kept in the order of 10−5. The electron beam from the gun is adjusted by both static and magnetic deflectors. The intermediate and projector lenses are adjustable to the optical axis of the objective lens merely by moving their pole pieces. All lenses can be replaced or removed from the side without disassembling the microscope body.