| 摘要 |
A display tube having an electron gun and an electron beam deflector including first and second electrode arrangements disposed successively along the electron beam path from the electron gun. Each electrode arrangement includes a pair of resistive plates extending transverse to the path of the electron beam and disposed on opposite sides of the path. The plates of each electrode arrangement are joined at their top and bottom ends and a potential difference is applied across the plates to provide electrical fields substantially normal to the electron beam path. The fields provided by the respective electrode arrangements are equal and opposite so that the angular deflection of the electron beam caused by the first electrode arrangement is cancelled by the second electrode arrangement and the electron beam leaves the electron beam deflector on a path parallel to (or coincident with) the path it entered the deflector. In order to ensure that no additional angular deflection of the electron beam occurs when it crosses the interface between the first and second electrode arrangements, the voltages applied to the second electrode arrangement are varied so that the point of entry of the electron beam is at an equipotential with that of the beam.
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