Optical waveguiding structures in living organisms. (a) Hand-cut
transverse section of a matur leaf of P. latifolia under
polarized light. E1: adaxial epidermis, E2: abaxial epidermis, m: mesophyll, S:
osteosclereids. Yellow arrows indicates veins, and dotted line indicates
paradermal section.[8] Scale
bar, 100 μm. (b) Lithops olivacea with green bodies and
large pinkish translucent windows through which sunlight penetrate into the
leaf.[9] (c)
Fenestrated Haworthia and Lithops with
translucent tissues.[89] (d)
Optical images of red laser light guided in (left) in a corn root and (right) in
an oat seedling.[10] Scale
bar, 1 mm. (e) Artistic drawing of a plant, illustrating light guiding through
the stem to the roots.[13] (f)
A cross-section image of the stem of a one-year-old Aesculus
turbinate. More efficient light guiding in the vascular tissue than
in pith.[12a] Scale bar, 1 mm.
(g) A cross-section image of the stem of a Fallopia japonica var.
uzenensis. More efficient light conduction in pith than in vascular
bundles.[12b] Scale
bar, 1 cm. (h) An inch-long jellyfish emitting bioluminescence light guided
through its transparent tissues.[90] (i) A cross-section imaging showing the longitudinal
organization of ommatidia in Australian desert ant..[91] Scale bar, 10 μm. (j)
A cross-sectional fluorescence imaging of a pig retina tissue slice, showing
Muller cells stained with a fluorescent dye (green). IPL: inner plexiform layer,
OPL: outer plexiform layer, NFL: nerve fiber layer.[20a] Scale bar, 10 μm.