Figure 3

Absorptive apodization and its impact.

(a) The setting of the hypothesized absorptive apodization. Low-level absorption (0.873 dB μm⁻¹) was implemented in the region with z > z_o and ρ > a. (b) Intensity distribution obtained from an apodized propagation simulation with (z_o, a) = (36, 2.3) μm. Blocking of the outermost fringe is evident. (c) The amplitude and phase profiles obtained at z = 67.4 μm at which the phase error δ_p becomes minimized. The dotted red curves represent LP₀₁ which also appeared in Fig. 2 d. The bulging in the amplitude profile for ρ ~ 2 μm persisted for other values of (z_o, a), necessitating additional mode shaping.