Diffraction Characteristics of a Linear Zone Plate*

The focusing, resolving, and diffracting properties of a linear zone plate in the neighborhood of the principal positive focus are examined theoretically and experimentally. The theoretical analysis employs both elementary and Kirchhoff diffraction theory; the experimental work was done using a helium–neon gas laser and a 200-line plate. A numerical comparison between theory and experiment shows good agreement for the choice of parameters employed.