Adaptive micro endoscopy using liquid crystal lenses with segmented electrodes (Conference Presentation)

Liquid crystalline (LC) materials are user friendly materials for electro optics applications [1], the most popular of which is the flat panel display [2]. Another interesting development, involving LCs, was the electrically variable lens that already had several commercial applications in DVD pick-up systems, Webcams and cell phones [3,4]. Their quality can be very high [5] and our team has recently demonstrated that they can be used in endoscopes for the study of deep regions of the brain [6]. We shall first describe various approaches explored to build electrically variable LC lenses. We shall then describe electrically variable LC lenses with segmented electrodes that enable almost adaptive optical capability, including the creation of a dynamic lens, prism, astigmatism and coma. This could be used to compensate various wavefront deformations in optical systems used to study various biological systems. We shall describe their advantages and drawbacks for the same application. References [1]. P.G. de Gennes and J. Prost, The Physics of Liquid Crystals, (Oxford University Press, 1995), 2nd Edition. [2]. Robert H. Chen, Liquid Crystal Displays: Fundamental Physics and Technology, Wiley, July 2011, ISBN: 978-0-470-93087-8. [3]. T. Galstian, Smart Mini-Cameras, CRC Press, Taylor & Francis group, Boca Raton, 2013. [4]. www.lensvector.com [5]. T. Galstian, K. Asatryan, V. Presniakov, A. Zohrabyan, A. Tork, A. Bagramyan, S. Careau, M. Thiboutot, M. Cotovanu, Optics Letters, Vol. 41, Issue 14, pp. 3265-3268 (2016),  doi: 10.1364/OL.41.003265. [6]. A. Bagramyan, T. Galstian and A. Saghatelyan, Journal of Biophotonics, 1–13 (2016) / DOI 10.1002/jbio.201500261.