ELECTROSTATIC DEFLECTION SYSTEM AND DISPLAY DEVICE

摘要

The invention relates to an electrostatic deflection system for deflecting an electron beam (132), and to a matrix display device provided with such an electrostatic deflection system. The deflection system has deflectors (112, 114) for the horizontal and vertical directions, and a focus electrode (110). By applying a sufficiently high voltage difference of for example several kiloVolts between the focus electrode (110) and at least one of the deflectors (112, 114), a bipotential type focusing electron lens is integrated with the deflection system. Thereby, the system achieves simultaneous deflection of the electron beam (132) and focusing of the electron beam onto a surface (140) to be scanned. In a matrix display device, the electron beam (332) may be kept in focus on the display screen (340) thereby obtaining a relatively small spot size and high image quality. Generally, the display screens divided into a number of portions (344). In operation, each portion is scanned by a separate electron beam (332).