This contribution explores the perceptions, ideas and understanding about the phase entropy of the ion-field interaction. Here we discuss the interaction between a single qubit (trapped ion) and a single laser field. We construct the explicit solution of this problem. Employing an obtained exact solution of the problem, significant features of the phase entropy in the context of the measure defined by phase probability distribution are observed. We discuss the relationship between entropic uncertainty relations and entanglement. Implications of the results for different physical parameters are discussed.