On the ellipse air holes of NR-PC flat lens for lightwave target detection and imaging

Influence of the cylinder air holes or ellipse air holes of negative-refraction photonic crystal (NR-PC) lens on the performance of lightwave target detection and imaging are studied with finite-difference time-domain (FDTD) method in the paper. Numerical simulations indicate that significant enhancement of the scattering signal can be obtained due to the use of the NR-PC flat lens; consequently, great improvement of the refocusing gain as well as the imaging resolution will be provided. We furthermore research the effects of different targets for detecting using NR-PC lens with cylinder air holes. Then we use ellipse air holes instead of the cylinder ones. By using different scanning scheme (lens-fixed scanning scheme and lens-combined scanning scheme), we find that its focusing resolution is better than the cylinder ones. At the same time, the resolution using lens-combined scanning scheme is always better than that using lens-fixed scanning scheme. So our investigation optimizes the performance of the focus-scanning scheme.

► Focusing resolution of NR-PC lens on the performance of lightwave target detection and imaging using dynamic scanning scheme.
► The scattering signal enhances four times than that without the NR-PC flat lens.
► The resolution using ellipse air holes is always better than that using cylinder ones.