Optical physics is a mature science, and there are tens of thousands of patents for optical devices. So it is dramatic and exceedingly rare for a young company to own the basic patents on a major, foundational technology. Varioptic owns the two key patents that protect the essential elements of a liquid, focusable lens, covering the concept of centering a liquid droplet and the geometry of a centering container that makes it possible to use a liquid as a lens. Bruno Berge led the research underlying these patents at the University of Grenoble, and Varioptic has acquired complete control of the patents from the university.

Patent n°1:
“Lens with variable focus"
priority date:  8th October 1997
International publication number:  WO 99/18456

Patent n°2:
"drop centering device"
International publication date: 5th october 2000
priority date: 26th march 1999
international publication number:  WO 00/58763

M. Vallet, M. Vallade et B. Berge, « Limiting phenomena for the spreading of water on polymer films by electrowetting », Eur. Phys. J. B11 (1999) 583-591.
Limiting phenomena (PDF 331 Ko)

C. Quilliet , Bruno Berge, « Investigation of effective interface potentials by electrowetting » Eurphysics letter, 1 october 2002PP 99-105
Investigation (PDF 127 Ko)

Invited review paper : Quilliet C., Berge B. : « Electrowetting: a recent outbreak », Current Opinion in Colloid & Interface Science (2001) 6 :11-16
Electrowetting (PDF 168 Ko)

Proceedings of the MEMS 2005 conference, held in Miami, USA Jan 30- Feb 3 2005-02-05
Proceedings (PDF 199 Ko)

B. Berge and J. Peseux; « Variable focal lens controlled by an external voltage: an application of electrowetting », Eur. Phys. J. E (2000) 3 p159-163.
Variable_focal_lens (PDF 146 Ko)

Bruno Berge, Claude Gabay et al, « Dynamic study of a Varioptic variable focal lens » , Proceedings of SPIE, 8-9 July 2002
Dynamic_study (PDF 125 Ko)

Lisa SAUREI, Gilles Mathieu, Bruno Berge, « Design of an autofocus lens for VGA ¼ CCD and Cmos sensor », proceedings of SPIE conference, October 2003.
spie_final (PDF 273 Ko)

Proceedings of the 10th MicroOptics conference, Jena Germany, September 1-3 2004
Proceedings (PDF 190 Ko)