Charge image charge transfer cathode ray tube having a scan expansion electron lens system and collimation electrode means

摘要

A cathode ray tube includes first and second electrostatic quadrupole lens between the electron gun and the vertical deflection plates to properly focus the electron beam before it enters the vertical deflection plates. A third electrostatic quadrupole lens is located between the vertical deflection plates and the horizontal deflection plates to enhance the angle of deflection as well as to aid in the proper focus of the electron beam as it moves from the vertical deflection plates into the horizontal deflection plates thereby providing substantially improved vertical sensitivity and scan expansion of the electron beam while maintaining the beam velocity constant. A collimation electrode means follows the horizontal deflection plates and flood gun means and is formed of conductive coatings having specific configurations disposed on the inner surface of the tube envelope thereby controlling the flood electrons to provide a more uniform flood electron beam to minimize landing angle of the flood electrons onto or through storage target means.