Shan, Mingguang Kandel, Mikhail E. Popescu, Gabriel Visualization 2: Refractive index variance of cells and tissues measured by quantitative phase imaging The phase second order derivative along x of the data in Video 1. The color bar indicates phase in units of (rad/µm)^2, as explained in the Fig. 2c caption. Originally published in Optics Express on 23 January 2017 (oe-25-2-1573) 23 January 2017;Optics Express;Video 1.;color bar;2 c caption;phase imaging 2017-01-23
    https://opticapublishing.figshare.com/articles/media/Visualization_2_Refractive_index_variance_of_cells_and_tissues_measured_by_quantitative_phase_imaging/4951199
10.1364/OE.25.001573.v002