Electrical polarization in thin, dielectric sheet material induced by handling or other means is not readily observed because the external field from a dipole charge layer is very weak compared with the field from net charges that are usually present. A method is described for measuring polarization in the presence of net charges by placing the dielectric sheet in contact with a grounded metal backing plate and by placing a field meter at a short distance in front of the dielectric. The grounded metal backing plate has the effect of almost completely annulling the external field of any net charge by induction, and of doubling the external field of a dipole charge layer of polarization.