Analysis of Kelvin Probe Operational Models
  We present a study of several models on which Kelvin Probe instruments with flat and spherical tips rely for operation and for the determination of the contact potential difference. Using covariance analysis, we have investigated the precision limits of each model as imposed by the Cramer-Rao bound. Where the situation demanded, we have evaluated the bias introduced by the method in the estimation of the contact potential difference. 
Eugeniu M. Popescu
physics.ins-det