25.2 Invited Paper: Recent Trends in CRT Cathodes

Image quality of CRTs has been improved by applying new technologies of electron gun, cathodes and image screen. Recently, new types of cathodes with higher current density have been developed, and have contributed higher definition and higher brightness of CRTs. This paper reviews of the recent technical progress in CRT cathodes, which are classified into thermionic cathodes and cold cathodes. Recently studies concerned with cold cathode for CRT application has been also reported, but this review focuses on thermionic cathodes which consist of Oxide-coated cathodes and Impregnated cathodes.