Resolution:
## Figure 1.
Dual-periodical multilayer structure. Schematic view of the 1D dual-periodic structure showing the layer parameters, where
n and m represent the period numbers of a and b in A and B substructures, respectively; n_{1} and n_{2} are high and low refractive indexes of alternating dielectric layers in a and b; the layer thickness is d_{1} and d_{2} for a, and d_{3} and d_{4} for b, respectively.
Estevez |