Expanding the measurement range of a critical-angle refractometer through Fourier analysis Junwei Ye, Min Xia, Hao Liu, Wei Li, Wenping Guo, Changxin Xiong and Kecheng Yang EPL, 104 2 (2013) 20001 Published online: 15 November 2013 DOI: 10.1209/0295-5075/104/20001