Fig. 5: Performance of multiple-order spatial differentiation for phase objects.

Bright field optical images of (a), (e) B16F10 melanoma cells and (c), (g) onion epidermis. b, d The second-order spatially differentiated images of the B16F10 melanoma cells and the onion epidermis, respectively. f, h The first-order spatially differentiated images of B16F10 melanoma cells and onion epidermis, respectively. The insets in (b), (d), (f), and (h) show magnified images of the regions marked using a line-box in each case.