PMC

Reflectance spectra of the Au nanofoam without dye (trace 1) and with HITC:PMMA (n = 36.5 g/L) (trace 2). Reflection spectra of smooth gold film without dye (trace 3) and with HITC:PMMA (n = 36.5 g/L) (trace 4). The ellipse shows the area, where the dip in the reflection spectrum of Au nanofoam, caused by the absorption of the HITC dye, is expected.

Effect of numbers of dip and pad on dyeing properties of DB₁ (dye concentration of 25 g/L, sodium carbonate of 12 g/L, dipping time of 3 min and steaming time of 15 min).

Optimization of rhodamine dye concentrations. a) The effect of varying dip concentrations. b) The relationship between dye concentration used and absorption. c) Images of the contact lenses dipped in different dye concentrations.

Bulk solution experiments. Upper panel: Dip Width (DW) versus Dip Position (DP) values for 25 different mixtures of B23 dye and sodium chloride salt. The directions of increasing dye concentration and increasing salt concentration are marked by arrows. The epigram vector is defined as being orthogonal to the direction of increasing salt concentration, while the ektogram vector is defined as being orthogonal to the direction of increasing dye concentration. Lower panels: Predicted versus actual concentration of dye (left) and salt (right) for the 25 mixtures (dots) and fitted straight lines (dotted).