Extended focal depth imaging using single and double peacock eye phase diffractive elements

The "peacock eye" phase diffractive element focuses an incident plane wave into a segment of the optical axis although it introduces certain amount of aberration. This paper evaluates the extended depth of focus imaging performance of the peacock eye phase diffractive element and explores some potential applications in ophthalmic optics. Two designs of the element are analyzed: a single peacock eye, which produces one focal segment along the axis, and a double peacock eye, which is a spatially multiplexed element, that produces two focal segments with partial overlapping along the axis. The performances of the peacock eye-based elements are compared with the performance of a multifocal lens in the image space through numerical simulations as well as optical experiments. In all the cases considered, we obtain the point spread function and the image of an extended object. The results are presented and discussed.