Abstract

A dielectric structured lens formed by varying the high-refractive-index square dielectric holes is proposed. This lens overcomes the limitation of feature size of the large numerical aperture (NA) lens, the energy efficiency has achieved 44% by finite difference and time domain (FDTD) algorithm, and the spot size leads to the diffraction limit. In addition, the substrate dielectric was optimized in the paper, the material of different dielectric-index for n=1, n=0.1, n=1.5 were choosed to analysis. And the dielectric of n=1 has the advantage of high energy efficiency, but it is difficult to realized. Then, the material of n=0.1 is a kind of meta material. The lens of this material has very low energy efficiency because of the strong reflection in the interface of the near-zero index meta materials and the other dielectrics. Last, the dielectric of n=1.5, it not only has the high energy efficiency, but also it is easy to be realized in craft.

© 2013 Optical Society of America