|
| |
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
|
Fig. 6. Two-dimensional Fourier power spectra of transmission electron micrographs
of structural colour producing butterfly scale nanostructures (Figs
4,
5). (A) Urania fulgens
blue (Fig. 4B), (B) Papilio
ulysses (Fig. 4E), (C)
Papilio zalmoxis (Fig.
4G), (D) Parides sesostris
(Fig. 4J), (E) Troides
brookiana (Fig. 4L), (F)
Troides urvillianus, (G) Callophrys dumetorum
(Fig. 5F), (H) Parrhasius
moctezuma (Fig. 5H) and
(I) Morpho aega (not illustrated). Colour scale (from blue to red)
indicates the relative magnitude of the squared Fourier components, which are
dimensionless quantities. Direction from the origin indicates the direction of
the 2D component waves in the image, and the distance from the origin
indicates the spatial frequency (cycles/nm) of each Fourier component. The
Fourier power peaks (red pixels) demonstrate predominant periodicities at
intermediate spatial frequencies. The distance from the origin is inversely
proportional to the wavelength of the coherently scattered colour.
|
