Coded aperture imaging of X ray or y ray emitting objects using on-axis Fresnel zone plate apertures was the original method suggested by Mertz in 1961. Since then other forms of coded aperture imaging have become more popular. We show in this paper that, under certain well-defined conditions, high quality images can be obtained with Mertz' original encoding method.
M. D. Tipton,
J. E. Dowdey,
H. J. Caulfield,
"Coded Aperture Imaging with On-Axis Fresnel Zone Plates," Optical Engineering 12(5), 125166 (1 October 1973). https://doi.org/10.1117/12.7971655