公开(公告)号：US5015925A

公开(公告)日：1991-05-14

申请号：US461888

申请日：1990-01-08

申请人： Tjerk G. Spanjer ,  Gerardus A. H. M. Vrijssen

发明人： Tjerk G. Spanjer ,  Gerardus A. H. M. Vrijssen

IPC分类号： H01J29/62

CPC分类号： H01J29/626 ,  H01J2229/4827

摘要： Picture display device comprising a display tube with an electron gun having a tubular structure with an outer surface and an inner surface on which a helical resistance structure is provided in a layer of a material having a high electrical resistance for constituting a focusing lens. In the layer is also formed a coaxial correction element for generating an electric multi-pole field. The outer surface is provided with electrodes of readily electrically conducting material arranged opposite the correction element for capacitively coupling a dynamic correction signal into the correction element.