We investigate a class of non-Hermitian, PT-symmetric Hamiltonians characterized by a potential matrix where the off-diagonal element V1,2(x) is null. We derive the analytical conditions necessary for the preservation of an unbroken PT-symmetry phase, thereby ensuring a purely real energy spectrum. The study identifies the exceptional points that mark the threshold of spontaneous PT-symmetry breaking. Leveraging these results, we construct exactly solvable models applicable to the study of beam dynamics in quantum optics and the behavior of complex wave systems, providing a theoretical framework for experimental realization.