Television camera tube with electrostatic focusing and magnetic deflection

摘要

A television camera tube with electrostatic focusing and magnetic deflection comprises in an cylindrical envelope (1) a beam current control section, a main lens section and a sixth grid in the form of a mesh electrode. The beam current control section includes a cathode (4), a first grid (5) and a second grid (6) with an electron beam limiting diaphragm (7) disposed in this order. The main lens section includes third, fourth and fifth grids (8, 9, 10) in the form of cylindrical electrodes disposed in this order. Around the cylindrical envelope is mounted a magnetic deflection coil (12) whose length (ℓ_D) along the envelope axis is 0.18 to 0.40 times the distance (L) from the beam limiting diaphragm (7) tho the mesh electrode (11).