Third-Order Self-Imaging with Thermal Light

Two kinds of theoretical schemes of third-order self-effect are proposed and analyzed, in which self-images of the object can be observed nonlocally in the two reference detectors. Plentiful self-imaging effects is presented in scheme I, where diffraction pattern of the periodic structure can be enlarged or diminished. In the scheme II, Talbot length is doubled that of the scheme I and the resolution may be improved by a factor of 2, and even higher. In the last, we discuss the similarities and the differences between self-imaging by third- and second-order process.