Imaging by a sub-wavelength metallic lens with large field of view.
The characteristics of the phase retardations and the invariability against the incident angles are investigated when light enters the rectangular holes with different sizes perforated on metallic film. A kind of metallic structure with a great potential in imaging is brought forward. The finite difference time domain (FDTD) method and the Rayleigh-Sommerfeld diffraction integrals are used to testify the imaging ability at different incident angles by examining the electric field on focal plane. The calculation results indicate that a quite large view of field lens can be achieved by increasing the number of the holes per unit area with the mentioned structure. A metallic structured lens with a 280 microm aperture and 240 microm focal length is designed and the view angle range of +/-15 degrees can be achieved.
State Key Laboratory of Optical Technologies for Microfabrication, Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209, China.
Shaoyun
S
Yin
Chongxi
C
Zhou
Xiangang
X
Luo
Chunlei
C
Du