Abstract: An improved electrostatic opposing field spectrometer of the type which may be utilized for undertaking measurements with an electron beam probe has an extraction electrode and an opposing field electrode and two spherical networks for generating a spherically symmetrical opposing field, the lower spherical network being at substantially the same potential as the extraction electrode and the upper spherical network being at a potential in the range of approximately 15 through -15 volts. The spherical network permit transmission of a large solid angle distribution of the secondary electrons emitted at the test point on the surface of a specimen. The centers of both spherical networks may be coincident at an imaginary source point.

Abstract: A corpuscular beam blanking system for generating high-frequency corpuscular pulses with monochromator effect utilizes a three-electrode Einzel-lens designed as a filter lens and which is employed as a blanking lens. A "breathing" effect of a probe spot of the corpuscular beam is avoided and a monochromator effect is achieved with a blanking pin-hole diaphragm positioned after the blanking lens.

Abstract: A high current electron source with a narrow energy band of the type employed in an electron beam printer has a beam generating system consisting of a cathode and focusing electrodes and an anode with at least one electrode functioning to astigmatically focus at least one electron crossover in the low velocity range. For varying the position and shape of the crossover in a simple manner for adaptation to particular use conditions of the high current electron source, the Wehnelt electrode of the electron source consists of one or more cylinder lenses or of an electrostatic multipole element, or an electromagnetic multipole element is disposed in the plane of a conventional non-ferromagnetic Wehnelt electrode with a circular aperture for the electron beam. By pole reversal of the Wehnelt voltage or of the coil current and by changing the size of the current, the shape and azimuth position of the first crossover in the cathode space can be varied to any configuration.