Figure 6.

Simulated resolution. Distribution of $I_f$ when $f=200 \mathsf{\mu }\mathrm{m}$ (a) and $600 \mathsf{\mu }\mathrm{m}$ (b). Calculated lateral (c) and axial (d) resolution vs. imaging numerical aperture ($iNA$). Here, resolution is defined by the 1/e full width of the signal intensity (i.e., $I_f$) fitted to a Gaussian function. Simulation parameters are the same as those in Figure 2, except $Z_0=1058 \mathrm{mm}$ (equal to 90 times average $Z_p$ minus 1 mm).