Device for generating electrons, and display device

摘要

A planar electron-optical lens is obtained on a semiconductor cathode surface by providing an extra electrode (16) around the gate electrode (14). Dependent on the applied voltage, this configuration operates, for example, as a positive lens which supplies parallel beams without dispersion, suitable for thin, flat display devices. A large positioning tolerance is obtained due to the inherent magnification of the beam diameter in the semiconductor device, while a grid can be dispensed with.