@inproceedings{ed3649df1a36412eb3b34b8ce91c3c2d,
title = "Wideband acoustic luneburg lens based on graded index phononic crystal",
abstract = "The present study proposes a wideband two-dimensional Luneburg lens using graded phononic crystals (GPCs). We present a method to broaden the range of operation frequency of the Luneburg lens based on GPCs. The GPCs is composed of circular cylindrical rods with triangular lattice air background. In long wavelength limit assumption, periodic structure behaves like a homogeneous medium since dispersion relations is almost linear. The effective refractive index can be tuned by adjusting the filling ratio. The plan wave expansion method is utilized to calculate the band structures of the locally GPCs and the effective refractive index of the locally GPCs with different filling ratio. Finite element simulations was employed to confirm the acoustic properties of designed device. Our numerical simulations demonstrate that the operation frequency range of GPCs of circular cylindrical rods arranged as triangular array is much wider than those of square array. A wideband acoustic Luneburg lens can be achieved by using graded phononic crystals of triangular array.",
author = "Wang, {Chia Fu} and Tsai, {Chia Nien} and Chang, {I. Ling} and Chen, {Lien Wen}",
year = "2015",
month = jan,
day = "1",
doi = "10.1115/IMECE201552927",
language = "English",
series = "ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE)",
publisher = "American Society of Mechanical Engineers (ASME)",
booktitle = "Vibration, Acoustics and Wave Propagation",
note = "ASME 2015 International Mechanical Engineering Congress and Exposition, IMECE 2015 ; Conference date: 13-11-2015 Through 19-11-2015",
}