COLOR SHADES® spectral filters arrays: a new dimension for multispectral imaging

Custom 2D Spectral filter arrays to replace standard Bayer matrices for imagers is an emerging technology for multispectral imaging. They allow to downsize multispectral cameras and systems while keeping their advantages compared to standard RGB cameras. SILIOS Technologies is developing such spectral filters arrays based on its Color Shades® technology. The first part of the talk will present the technology and its evolution from spectrometry, with lower constraints, to multispectral imaging. The second part will show the developments made at SILIOS Technologies for multispectral imaging, the advantages of these spectral filters arrays and the progress and current development to improve the capacities of the technology as well as the next steps of evolution.The Color Shades® technology allows to choose the wavelengths range, the number of different wavelengths between 2 to 16, the size and shape of each filter. Applied to spectrometry, it offers the possibility to realize applications dedicated compact spectrometers and for imaging it brings multi-spectral capabilities to standards imagers.

The Color Shades® technology brings a new dimension to spectral imaging thanks to its full versatility in terms of wavelengths choices, choice of the position of each different colorpixel in the matrix and to the possibility to match one filter per pixel. The Color Shades® Custom Bayer matrix is realized on a thin fused silica substrate which is reported face down on the sensitive part of the imager to avoid crosstalk. The current realizations are for the visible range (400 – 700nm) and the Near Infrared range (700-1000nm). The first matrices where made with 20×20μm² ranges and 4 wavelengths (RGB plus one NIR). The current realizations concern also 20×20μm² range pixels but with 7 visible range wavelengths and one NIR band and the future developments will lead to come down to imagers’ pixel size (i.e. ≤ 5 μm).


Thierry Berthou received the Engineering degree in optics from Ecole Nationale Supérieure de Physique de Marseille (now Centrale Marseille), France, in 1990. Between 1990 and 1992, as a development engineer and project manager, various optical complex systems and simulators such as an all-weather detection system and an image recognition system for a packet sorting robot were developed.

Between 1993 and 1995 he was R&D Manager and led six projects within EUREKA, MAST, THERMIE, HYDROACARB, BRITE-EURAM programs. Since 1996 he has been Sales & Export Sales Manager for companies working in the fields of Radars, semiconductors and optics industries. He joined SILIOS in 2005 where he has been Project leader of a EUROSTARS project and Principal Investigator of 2 FP6-IST projects. He has authored more than 10 communications in various technological fields (corrosion inspection by Eddy-currents, Lithography using laser beam Interference, Diffractive Optics…).