Fabien Lemarchand wins the "Black Box Coating Challenge" (Design Problem Contest) at the OIC 2022 International Conference on 21 June 2022 at Whistler (Canada)
Finding the formula of a mystery stack from only data resulting from optical characterizations R and T as a function of angle of incidence and wavelength, such was the challenge offered to about twenty participants from all over the world, specialists in the design of thin film stacks.
Among the a priori knowledge provided by the statement, the possibility of 20 different optical indices for the layers without indication of thickness, and a number of layers between 1 and 75, remained secret...
Fabien Lemarchand from the thin-film research (RCMO) team of the Institut Fresnel, the only one to find the exact formula, including 50 layers with precise thicknesses between 48.4 and 310.9 nm, was thus the winner of this tri-annual competition for the 4th time since 2004.
This result illustrates once again the unique international know-how that has been developed by Fabien at Institut Fresnel for more than 20 years.