Grid arrangement for vidicon tube with pyroelectric target plate - gives optimum control of ratio between ion and electron flows

摘要

The vidicon with a pyroelectric target plate (T) and filled with a gas, is a designed for improved contrast. The tube (R) has a cathode (K) followed by a control grid (G1) and a drain anode (G2). At the sides is a focusing grid (G3) and a field network (G4) is in front of the target plate. The ions resulting from the electron beam can pass the control grid (G1) at low potentials and reach the field network, the ion flow being regulated by this grid. The arrangement gives an optimum control of the radio between the ion and electron flows inside the tube.