Three-dimensional point spread function and generalized amplitude transfer function of near-field flat lenses.
We derive a nonsingular, polarization-dependent, 3D impulse response that provides unambiguously the wave field scattered by a negative-refractive-index layered lens and distributed in its image volume. By means of a 3D Fourier transform, we introduce the generalized amplitude transfer function in order to gain a deep insight into the resolution power of the optical element. In the near-field regime, fine details containing some depth information may be transmitted through the lens. We show that metamaterials with moderate absorption are appropriate for subwavelength resolution keeping a limited degree of depth discrimination.
Departamento de Óptica, Universidad de Valencia, Dr. Moliner 50, 46100 Burjassot, Spain. carlos.zapata@uv.es
Carlos J
CJ
Zapata-Rodríguez
David
D
Pastor
Juan J
JJ
Miret