Figure 6.

(A) Transmission spectra of the structure printed using the DN gel structure. The printed structure is placed on the top of the BioInspired Institute logo to demonstrate the high transmissivity of the DN gel structure (scale bar—1 cm). (B) CAD design, computer-generated digital masks, and 3D-printed axicon lens using TOPS (scale bar—2 mm). (C) Characterization of the annular ring while the axicon lens is static (scale bar—2 cm). (D) Optical setup to characterize the annular ring of the axicon lens during dynamic stretching. (E) A screenshot was obtained from Video V4 showing the tunability of the axicon lens (scale bar—3 cm). (F) Schematic showing the zero-order Bessel beam generation by the axicon and experimentally obtained annular rings before and after stretching the axicon lens (scale bar—2 cm). ω_b = radius of the central lobe, z_b = length of Bessel region, D₀ = diameter of incident beam.