Linear Correction for Cathode Ray Oscillograph

Abstract

The deflection of the cathode beam in a cathode-ray oscillograph tube, while substantially proportional to the voltage applied to the deflecting plates within the tube, is not proportional for small voltages in tubes commonly used. This non-linearity is due to the heavy cloud of ions between the plates. In the practical use of such a tube error due to this non-linearity is avoided by applying a bias to the plates so as to work on the straight part of the curve.