Improved image quality of a Ag slab near-field superlens with intrinsic loss of absorption.
Intrinsic loss of absorption in the Ag slab near-field superlens turned out to add a blurring effect to the ideal image reconstruction for the impedance match case. By optimizing the real part of the permittivity (epsilon') of Ag, our FDTD calculation predicts approximately 69% enhancement of visibility and approximately 138% increased depth of field for the intensity contrast of 0.5 with similar focal spot size. For a near-field superlens with the higher absorption loss, the optimized image quality is obtained with a larger impedance mismatch, which can be realized by changing the wavelength of incident light for imaging.
School of Mechanical Engineering, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-749, Republic of Korea. kks@yonsei.ac.kr
Kwangchil
K
Lee
Haesung
H
Park
Jaehoon
J
Kim
Gumin
G
Kang
Kyoungsik
K
Kim
D016477:Artifacts; D007089:Image Enhancement / Q000379:methods*; D007909:Lenses; D008027:Light; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D012542:Scattering, Radiation; D012834:Silver / Q000737:chemistry*
D012834:Silver