1. Inkjet Printed Laser Arrays D.J. Gardiner, 1 W-K. Hsiao, 2 S.M. Morris, 1 P.J.W. Hands, 1 T.D Wilkinson, 1 I. M. Hutchings 2 and H.J. Coles 1 1 CMMPE, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge, UK 2 Inkjet Research Centre, Institute for Manufacturing, Department of Engineering, www-g.eng.cam.ac.uk/CMMPE This work is funded by the “COSMOS TT” EPSRC Technology Translation Grant, EP/H046658/1 Paintable LC lasers Advantages: Simple process Disadvantages: Limited spatial control Laser dye + Chiral nematic LC + Polymer (PVA) Lasing emulsion Film shrinkage during drying induces LC alignment Inkjet LC lasers Direct printing onto glass does not give sufficient uniformity = multi-mode output Experimental: LC Mixture: BDH-1281 in BL006, Laser dye – 1% Pyrromethene-597. Inkjet: 10 wt. % PVA film, Microfab printing device (droplet volume 200 - 300 pl). References: D. J. Gardiner et al Opt. Express. 2011, 19, 2432. P. J. W. Hands et al, Appl. Phys. Lett. 2011, 98. New Process – Wet layer printing Inkjet LC laser array Complex & functional laser patterns on any substrate Impact process: surface tension, immiscibility and interfacial interaction induce standing helix alignment Droplet Deposition Lasing: (Nd:YAG) laser (Polaris II, New Wave Research), 3-4 ns pulse duration, repetition rate 1 Hz, 110 µm

2. LC laser publications from CMMPE, University of Cambridge (2006-2012) For full list, see: http://www-g.eng.cam.ac.uk/CMMPE/publications.html Density of photon states in dye-doped chiral nematic liquid crystal cells in the presence of losses & gain Th.K. Mavrogordatos, S.M. Morris, F. Castles, P.J.W. Hands, A.D. Ford, H.J. Coles, T.D. Wilkinson Physical Review E, 86, 011705, (2012) Electrically switchable random to photonic band-edge laser emission in chiral nematic liquid crystals S.M. Morris, D.J. Gardiner, P.J.W. Hands, M.M. Qasim, T.D. Wilkinson, I.H. White, H.J. Coles Applied Physics Letters, 100, 071110, (2012) Lowering the excitation threshold of a random laser using dynamic scattering states of an organosiloxane SmA liquid crystal S.M. Morris, D.J. Gardiner, M.M. Qasim, P.J.W. Hands, T.D. Wilkinson, H.J. Coles Journal of Applied Physics, 111 (3), 033106, (2012) Wavelength-tuneable liquid crystal lasers from the visible to the near-infrared P.J.W. Hands, C.A. Dobson, S.M. Morris, M.M. Qasim, D. J. Gardiner, T.D. Wilkinson, H.J. Coles Proc. SPIE, 8114, p. 81140T, (2011) Paintable band-edge liquid crystal lasers D.J. Gardiner, S.M. Morris, P.J.W. Hands, C. Mowatt, R. Rutledge, T.D. Wilkinson, H.J. Coles, Optics Express, 19, 2432, (2011) Band-edge and random lasing in paintable liquid crystal emulsions P.J.W. Hands, D.J. Gardiner, S.M. Morris, C. Mowatt, T.D. Wilkinson, H.J. Coles, Applied Physics Letters, 98, 141102, (2011) Liquid crystal lasers H. Coles, S.M. Morris Nature Photonics, 4, 676, (2010) Red-green-blue 2D tuneable liquid crystal laser devices and displays H.J. Coles, S.M. Morris, A.D. Ford, P.J.W. Hands, T.D. Wilkinson Liquid crystal microlasers, Ed. L.M. Blinov, R. Bartolino, Transworld Research Network, Ch.13, (2010) High slope-efficiency liquid crystal lasers C. Mowatt, S.M. Morris, T.D. Wilkinson, H.J. Coles Applied Physics Letters, 97 (25), 251109, (2010) Comparison of the performance of photonic band-edge liquid crystal lasers using different dyes as the gain medium C. Mowatt, S.M. Morris, M.H. Song, T.D. Wilkinson, R.H. Friend, H.J. Coles Journal of Applied Physics, 107, 043101, (2010) Removing the discontinuous shift in emission wavelength of a chiral nematic liquid crystal laser S.M. Morris, A.D. Ford, H.J. Coles Journal of Applied Physics, 106, 023112, (2009) Polychromatic liquid crystal laser arrays towards display applications S.M. Morris, P.J.W. Hands, S. Findeisen-Tandel, R.H. Cole, T.D. Wilkinson, H.J. Coles Optics Express, 16 (23), 18827-18837, (2008) Two-dimensional liquid crystal laser array P.J.W. Hands, S.M. Morris, T.D. Wilkinson, H.J. Coles Optics Letters, 33 (5), 515-517, (2008) Emission characteristics of a homologous series of bimesogenic liquid crystal lasers A.D. Ford, S.M. Morris, M.N. Pivnenko, C. Gillespie, H.J. Coles Physical Review E, 76, 051703, (2007) The emission characteristics of liquid crystal lasers S.M. Morris, A.D. Ford, C. Gillespie, M.N. Pivnenko, O. Hadeler, H.J. Coles Journal of the SID, 14(6), 565-573, (2006) Photonics and lasing in liquid crystals A.D. Ford, S.M. Morris, H.J. Coles Materials Today, 9(7-8), 40-42, (2006)