Annick Bay, Olivier Bergeron, Serge Berthier (organizer), P. Laszlo Biro, Laure Bonnaud, Julie Boulenguez, Frédéric Durieu, Pascal Goetgheluck, Beatriz Julian-Lopez, Jacques Lafait, Michel Menu, Lionel Nicole, Marie Rassart, Franziska Schenk, Catherine Sirot, Jean-Pol Vigneron (1950-2013)
Biophotonique – Bioinspiration
by Serge Berthier
30 March – 4 April 2009
This symposium brought together 16 persons from five European countries: Great Britain, Hungary, Spain, Belgium and France, and from different areas: art, science and industry, having in common the study or use, from these different points of view, natural photonic structures or bioinspired photonic structures. These structures allow the manipulation of light and will replace long-term electronics in our daily lives. However, there are actually significant problems for developing photonic structures, particularly the three-dimensional ones. There are however a considerable number in the wild. Natural photonic structures have many qualities. (1) – They meet a number of vital common to living organisms and have been optimized and tested over the millennia. (2) – They have the merit to exist already in all dimensions, particularly the 3 dimensions so difficult to produce.
From a “material” point of view, the nature produces these structures from a relatively small number of components, all dielectric (air, water, physiological fluid, chitin …) characterized from an optical point of view by a narrow range of index (significantly from 1 to 1.6), which limits the contrast. To overcome this relative poverty, nature has developed, under the combined effect of mutations and selection, an impressive array of structures.
Various chemical or physical techniques are now able to produce or reproduce these structures and, if it is difficult to design such structures without prior information on their potential properties, we have many different types of materials (dielectric, conductor, semiconductor, composite …) to achieve them.
This is that vast almost blank field of complex structures, inspired by nature, but made from varied materials, with a large variety of refractive index, that we have explored during the symposium.
All presentations can be assembled around three main themes:
(1) – natural photonic structures and their associated physical properties.
(2) – The bioluminescence and its applications. (3) The bioinspired photonics devices, and beyond.
1 – The photonic structures have been addressed from different points of view. Scientific first, with a study of topological disorder in the longhorns (JP Vigneron – FUNDP – Namur) and of the hydro chromic properties of certain insects (M. Rassart – FUNDP – Namur). The complex role of colour of cephalopods, both structural and pigment was introduced by L. Bonnaud, (MNHN – Paris) and a presentation of an exhaustive study of optical properties of Morphos by S. Berthier (INSP – Paris). The experimental techniques and theoretical approaches to characterize and model the multi-scaled photonic structures, taking into account their intrinsic disorder, were presented by Julie Boulenguez (INSP – Paris). From an artistic point of view then, with a presentation of the colourfull effects associated with artificial structures in the religious and secular works or by natural (feathers) in the South American civilizations pre-and post-Colombian (M. Menu – C2RMF – Paris). During the same conference, documentary films on the interferential colours of hummingbirds and interferential imaging, created by Maurice Françon in the sixties and recently digitized were also presented. Finally, the painter Franziska Schenk (London) presented his work on the structural effects captured on canvas with different contemporary pigments. The wildlife photographer P. Goetgheluck (Paris) presented, along with some of his news, his techniques of macrophotography, still problematic for uninitiated. A collaborative project for shooting iridescent insects in flight has been developed between the photographer and the teams in Paris and Namur.
2 – The bioluminescence. Along with photonic crystals, it is also necessary to develop light sources, mainly LEDs, which provide light. However, manufactured on the basis of semiconductor with index relatively high, a substantial portion of the light produced cannot be extracted from the diode, being totally reflected within the device. Many animals, however, have a surprisingly high radiative balance. This was presented by Annick Bay (FUNDP – Namur). In the same time, The painter Cat Sirot (Paris), presented paintings incorporating luminescent pigments, allowing a different reading of the work day and night. The problems resulting from the co-existence of luminescent and non luminescent pigments in the same binding have been analyzed by present chemists (Lionel Nicole and Beatriz. Julian Lopez) and a joint study undertaken.
3 – Bioinspired devices . The latter were the subject of many presentations. Jacques Lafait (INSP – Paris) gave a broad overview of recent achievements in bioinspired optical devices but also in other areas such as mechanics, tribology. Laszlo P. Biro (RITPMS – Budapest) presented some achievements made in his institute, including a steam detector based on Morpho wing. Concerning chemistry, Beatriz Julian Lopez (DQIO – Castellon) presented the first attempt to reply, in titanium oxide, the complex structure of a scale of Morpho rhetenor. Lionel Nicole (LMCC – Paris) took stock of the wider variety of techniques of chemistry to replicate or produce such structures. Collaboration is working with the INSP to develop this approach.
Finally, future uses of natural photonic structures in virtual reality have been mentioned by Olivier Bergeron, director of the company ByVolta (Paris) and Frédéric Durieux (The CielEstBleu – Paris).
During this symposium, which brought together renowned personalities from five European countries (Great Britain, Hungary, Spain, Belgium and France) and from different cultures (scientific, artistic and industrial), that vast field of investigation, practically blank, has been explored from different points of view, thereby laying the basis of new further cooperation that would have had only very little chance to arise apart from the context of the foundation.