Trajectory equations are derived in closed form for electrons in timehyphen;dependent electric fields produced by beam blankers. Simple parallel plate and doublehyphen;deflection blankers with transmission delay lines are evaluated. Lens imaging of the apparent beam motion is analyzed by developing the virtual electron trajectories obtained from linear extrapolation back into the blanker region. Lens excitation effects and conjugate blanking optics can then be described. The blanker voltage is represented by a damped exponential cosine term, which satisfies a typical circuit equation for the driverhyphen;amplifier. The form of the trajectory equation is written as a 3times;3 matrix, which comprises a set of conditional solutions that are determined by blanker geometry. The optimum delay line length of any doublehyphen;deflection blanker can then be determined. The blankerhyphen;induced beam jitter is shown to be significantly reduced by using this configuration. The effect of the blanker beam stop on the motion at the target plane is given by combining results on the real and apparent beam trajectories.
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