Enhance the resolution of photonic crystal negative refraction imaging by metal grating.

Department of Optics and Optical Engineering, University of Science and Technology of China, Hefei, Anhui, China.
Optics Letters (Impact Factor: 3.39). 02/2012; 37(3):359-61. DOI: 10.1364/OL.37.000359
Source: PubMed

ABSTRACT The resolution of imaging is limited by the missing of high-frequencies information. The superlens employing negative refraction can compensate for these components. But for the directional coupling of Bloch waves and the low coupling efficiency of large-angle waves, the resolution of subwavelength imaging is not satisfactory. However, the subwavelength metallic grating can produce high-order diffracted waves carrying a lot of high-frequencies information. Therefore, this structure is used to inhibit the zero-order diffraction and enhance the high-order diffraction to achieve super-resolution.

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