Fig. 4.

Human skin imaging. (a) 3D image captured by 300 μm × 3 μm NB. Despite the wavy surface, all surface features are distinguishable due to the long DOF. Scale bar, 200 μm; XY= 1 mm × 1 mm. (b) B-scans at y = 360 μm, blue plane in (a). Indicated by blue arrows, the dermal-epidermal junction in deep regions are fuzzy in Gaussian imaging (upper) but clear in 300 μm NB imaging (lower). Scale bar, 100 μm. (c) XY images at z = 250 μm, red plane in (a). The left figure is taken by Gaussian beam, and the right is by 300 μm NB. Some comparisons are marked by red arrows. Two insets describe the contrast profiles along the red dashed lines. The contrast is the ratio of the intensity along the red dashed lines to the average intensity of the air gap (background). Scale bar, 100 μm.