Biomedical Engineering Reference
In-Depth Information
to clarify the underlying physical mechanisms
[14]
. Rayleigh strongly supported the idea that
the brilliant colors of hummingbirds, butter-
flies, and beetles are caused by multilayer
interference. Shortly after Rayleigh, using the
basic optical phenomenons such as scat-
tering, interference, and diffraction, Bancroft
explained the iridescent colors of specific
insects, birds, and fish; gemstones; and natural
phenomena such as sunsets, rainbows, and the
blue color of the sky. Then Mason elucidated
the relationship between the structural fea-
tures and the colors of a variety of birds and
insects and provided simple methods for
distinguishing between pigment colors and
structural colors when present in insects, either
singly or in combination.
However, a better understanding of biologi-
cal iridescence began to emerge after electron
microscopes were pressed into service
[15]
.
From the 1970s to the mid-1990s, Allyn and
Downey
[16-18]
, Ghiradella
[3, 4, 19-23]
, and
Tabata and colleagues
[5, 24]
described several
biologically occurring arrays of uniformly
repeating structures that interact with light to
produce color. These developments led to
another wave of extensive studies on struc-
tural colors, motivated mainly by applications
for cosmetics, automobiles, and textiles of new
materials to provide coloration without the use
of hazardous chemicals. Notable applications-
oriented research has been carried out by
Kinoshita and colleagues
[11, 25-27]
and the
group of Saito
[28, 29]
. Vukusic and collabora-
tors
[30-33]
as well as Parker and collaborators
[34-36]
look for insects displaying unusual
structural colors to identify natural structures
that could be reproduced artificially without
loss of optical functionality. Other efforts wor-
thy of mention have been reported by Vign-
eron
et al
.
[37]
, Michielsen and Stavenga
[38]
,
Galusha
et al.
[39]
, and Sato and colleagues
[40]
. During the last few years, a few topics
have covered a wide range of topics related to
FIGURE 11.3
Top: A male peafowl (
Pavo cristatus
) dis-
playing its tail feathers. Middle: Close-up view of the tail
feathers of the male peafowl. Bottom: Common grackle
(
Quiscalus quiscula).
