Microwave power combining using the Talbot effect

In the 1830s H.F. Talbot discovered the Talbot effect, also known as self or lensless imaging [1]. As shown in figure 1, this near-field effect allows that at specific distances, a grating under plane wave illumination yields exact copies of the one-or two-dimensional periodic grating pattern. The effect was observed under certain conditions when a beam of light was reflected from and/or transmitted through an amplitude or phase periodic structure.