  This work presents the design and fabrication of simple, polymeric,
structure-based optical filters that simultaneously focus light. These filters
represent a novel design at the boundary between diffractive optics and
metasurfaces that may provide significant advantages for both digital and
hyperspectral imaging. The fabrication process for the proposed filters
resembles 3D printing, and is based on direct laser writing of a polymeric
material using two-photon lithography. In addition, printed structures could be
used to create molds for nanoimprint replication and mass production. Filters
for visible and near-infrared wavelengths were designed using finite difference
time domain (FDTD) simulations.
