Wildlife Photographer of the Year - People's Choice
The bird's wing acts as a diffraction grating - a surface structure with a repeating pattern of ridges or slits. The structure causes the incoming light rays to spread out, bend and split into spectral colours, producing this shimmering rainbow effect.
An enlarged view of the iris agate specimen with backlighting. This view is at a slightly different angle than the other backlighted view also pinned. It demonstrates that the spectral colors change with the angle of incident light and observation.
A 43.19 carat faceted Scapolite from Dodoma, Tanzania with a series of parallel rows of dotted inclusions running through the stone at angles which follow the crystals growth. The tightly spaced inclusions, assumed to be Pyrrhotite, serve as a diffraction grating, causing a vivid iridescent display. This unique effect gives rise to the term "Rainbow Scapolite" being used by some gem enthusiasts to describe these rare and unusual gemstones.
opal - The cause of the brilliant play of colors in opal was an enigma until relatively recently. Scanning electron microscope studies show that opals consist of transparent spheres of silica that are tightly packed. The voids or spaces between the spheres contain air or water. The regular arrangement of spheres acts as a diffraction grating, breaking visible white light into separate colors.
Vote for your favourite wildlife image of the year – in pictures
Rainbow wings by Victor Tyakht (Russia) The bird’s wing acts as a diffraction grating – a surface structure with a repeating pattern of ridges or slits. The structure causes the incoming light rays to spread out, bend and split into spectral colours, producing this shimmering rainbow effect, captured here by Victor.