Inhomogeneous media are affected by a physical or an electromagnetic field, where the off-diagonal elements of the Jones matrix are complex numbers with both real and imaginary parts. Inhomogeneities of the electromagnetic field result in the eigenvalue coordinate system changing along the light path. In this study, we used the unitary transformation to propose a Jones matrix of the inhomogeneous-field-induced medium with three physical or electromagnetic parameters: the medium's phase delay, induction angle, and inhomogeneous angle. This Jones matrix and the integral formulas of its three parameters are applicable to not only remarkable optical effects but also for the light propagation process of inhomogeneous-field-induced media.