Classical information entropy and phase distributions of optical fields

The Wehrl phase distribution is defined as a phase density of the Wehrl cla ssical information entropy. The new measure is applied to describe the quan tum phase properties of some optical fields including Pock states, coherent and squeezed states, and superposition of chaotic and coherent fields. The Wehrl phase distribution is compared with both the conventional Wehrl entr opy and Husimi phase distribution (the marginal Husimi Q-function). It is s hown that the Wehrl phase distribution is a good measure of the phase-space uncertainty (noise), phase locking and phase bifurcation effects. It is al so demonstrated that the Wehrl phase distribution properly describes phase randomization processes, and thus can be used in a description of the quant um optical phase.