Artificial Bee Eye Gives Insight Into Insects’ Visual World

Artificial Bee Eye Gives Insight Into Insects’ Visual World

  2:21:00 PM    Science Lover

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Despite their tiny brains, bees have remarkable navigation capabilities based on their vision. Now scientists have recreated a light-weight imaging system mimicking a honeybee's field of view, which could change the way we build mobile robots and small flying vehicles.

Bee eye view. (Credit: Image courtesy of Institute 
of Physics)

New research published Aug. 6 in IOP Publishing's Bioinspiration & Biomimetics, describes how the researchers from the Center of Excellence 'Cognitive Interaction Technology' at Bielefeld University, Germany, have built an artificial bee eye, complete with fully functional camera, to shed light on the insects' complex sensing, processing and navigational skills.

Consisting of a light-weight mirror-lens combination attached to a USB video camera, the artificial eye manages to achieve a field of vision comparable to that of a bee. In combining a curved reflective surface that is built into acrylic glass with lenses covering the frontal field, the bee eye camera has allowed the researchers to take unique images showing the world from an insect's viewpoint.

In the future, the researchers hope to include UV to fully reflect a bee's colour vision, which is important to honeybees for flower recognition and discrimination and also polarisation vision, which bees use for orientation. They also hope to incorporate models of the subsequent neural processing stages.

As the researchers write, "Despite the discussed limitations of our model of the spatial resolution of the honeybees compound eyes, we are confident that it is useful for many purposes, e.g. for the simulation of bee-like agents in virtual environments and, in combination with presented imaging system, for testing bee-inspired visual navigation strategies on mobile robots."

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Butterflies' Wings to Bank Notes

Butterflies' Wings to Bank Notes

  9:06:00 PM    Science Lover

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Scientists have discovered a way of mimicking the stunningly bright and beautiful colours found on the wings of tropical butterflies. The findings could have important applications in the security printing industry, helping to make bank notes and credit cards harder to forge.

The bright green wings of the P. blumei butterfly 
result from the mixing of the different colors of light 
that are reflected from different regions of the scales 
found on the wings of these butterflies. 
(Credit: Mathias Kolle, University of Cambridge)

The striking iridescent colours displayed on beetles, butterflies and other insects have long fascinated both physicists and biologists, but mimicking nature's most colourful, eye-catching surfaces has proved elusive.

This is partly because rather than relying on pigments, these colours are produced by light bouncing off microscopic structures on the insects' wings.

Mathias Kolle, working with Professor Ullrich Steiner and Professor Jeremy Baumberg of the University of Cambridge, studied the Indonesian Peacock or Swallowtail butterfly (Papilio blumei), whose wing scales are composed of intricate, microscopic structures that resemble the inside of an egg carton.

Because of their shape and the fact that they are made up of alternate layers of cuticle and air, these structures produce intense colours.

Using a combination of nanofabrication procedures -- including self-assembly and atomic layer deposition -- Kolle and his colleagues made structurally identical copies of the butterfly scales, and these copies produced the same vivid colours as the butterflies' wings.

According to Kolle: "We have unlocked one of nature's secrets and combined this knowledge with state-of-the-art nanofabrication to mimic the intricate optical designs found in nature."

"Although nature is better at self-assembly than we are, we have the advantage that we can use a wider variety of artificial, custom-made materials to optimise our optical structures."

As well as helping scientists gain a deeper understanding of the physics behind these butterflies' colours, being able to mimic them has promising applications in security printing.

"These artificial structures could be used to encrypt information in optical signatures on banknotes or other valuable items to protect them against forgery. We still need to refine our system but in future we could see structures based on butterflies wings shining from a £10 note or even our passports," he says.

Intriguingly, the butterfly may also be using its colours to encrypt itself -- appearing one colour to potential mates but another colour to predators.

Kolle explains: "The shiny green patches on this tropical butterfly's wing scales are a stunning example of nature's ingenuity in optical design. Seen with the right optical equipment these patches appear bright blue, but with the naked eye they appear green.

"This could explain why the butterfly has evolved this way of producing colour. If its eyes see fellow butterflies as bright blue, while predators only see green patches in a green tropical environment, then it can hide from predators at the same time as remaining visible to members of its own species."

Notes to editors: Mathias Kolle et al, 'Mimicking the colourful wing scale structure of the Papilio blumei butterfly' is published in Nature Nanotechnology on 30 May 2010.

The research was funded by the Engineering and Physical Sciences Research Council and the Cambridge Newton Trust.

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