In order to realize light-driven dynamic alignment of liquid crystal (LC) molecules
photo-responsive cholesteric liquid crystalline composite was prepared by doping chiral overcrowded alkenes into achiral LC hosts. The variation of helical pitch and the dynamic homogeneous alignment of LC molecules in photo-responsive cholesteric liquid crystals (ChLCs) were investigated upon UV exposure with different intensities. The dynamic reconfiguration from focal conic to planar state was demonstrated based on the UV-intensity addressability of the helical pitch. The response time for dynamic homogeneous alignment of planar state can be accelerated from 600 s to 60 s with the increase of UV intensity
whereas the random alignment of focal conic state was developed in the absence of high-power UV exposure due to the sharp fluctuation of helical pitch. To properly modulate the intensity of UV light in multi-procedure protocols
the dynamic alignment technology with rapid response and stable homogeneousness was achieved.
SLUCKIN T J, DUNMUR D A, STEGEMEYER H. Crystals that flow:Classic Papers From the History of Liquid Crystals [M]. London:Taylor & Francis, 2004.
WU S T, YANG D K. Reflective Liquid Crystal Displays [M]. UK:Wiley, 2001.
SUN J, ZHANG W, WANG M, et al . Bandwidth Tunable Cholesteric Liquid Crystal[M]. Liquid Crystal Sensors , CRC Press. 2017:1-32.
YOKOYAMA H. Surface anchoring of nematic liquid crystals[J]. Molecular Crystals and Liquid Crystals , 1988, 165(1):265-316.
CUI Y, ZOLA R S, YANG Y C, et al . Alignment layers with variable anchoring strengths from Polyvinyl Alcohol[J]. Journal of Applied Physics , 2012, 111(6):063520.
HASEBE H, MARUYAMA K, TAKASHIMA M, et al . 29.3:Performance of Novel LC-Photo-Aligning Cinnamoyl Side-Chain Polymers[J]. SID Symposium Digest of Technical Papers, 2014, 45(1):389-392.
ZHOU X Q, YANG L, LIU Z M, et al . Effects of PI post-bake time and UV dosage on LCD optical performance and image sticking by photo-alignment[J]. Chinese Journal of Liquid Crystals and Displays , 2017, 32(8):596-600. (in Chinese)
OZAKI R, SHINPO T, MORITAKE H. Improvement of orientation of planar cholesteric liquid crystal by rapid thermal processing[J] . Applied Physics Letters , 2008, 92(16):163304.
WANG F F, CAO H, LI K X, et al . Control homogeneous alignment of chiral nematic liquid crystal with smectic-like short-range order by thermal treatment[J]. Colloids and Surfaces A:Physicochemical and Engineering Aspects , 2012, 410:31-37.
OZAKI R, SHINPO T, OZAKI M, et al . Lasing in cholesteric liquid crystal oriented by acoustic streaming[J]. Japanese Journal of Applied Physics , 2008, 47(2S):1363-1366.
TERRAS J, RODRIGUEZ-ROPERO F, BERTRAN O, et al . Controlled isomerization of a light-driven molecular motor:a theoretical study[J]. Journal of Physical Chemistry C , 2009, 113(9):3574-3580.
RUANGSUPAPICHAT N, POLLARD M M, HARUTYUNYAN S R, et al . Reversing the direction in a light-driven rotary molecular motor[J]. Nature Chemistry , 2011, 3(1):53-60.
VICARIO J, WALKO M, MEETSMA A, et al . Fine tuning of the rotary motion by structural modification in light-driven unidirectional molecular motors[J]. Journal of the American Chemical Society , 2006, 128(15):5127-5135.
CANO R. An explanation of Grandjean discontinuities[J]. Bulletin de La Societe Francaise Mineralogie Et de Cristallographie, 1968, 91:20-27.
CHANDRASEKHAR S. Liquid Crystals [M]. New York:Cambridge University Press, 1997.
ZHANG F, YANG D K. Evolution of disclinations in cholesteric liquid crystals[J]. Physical Review E , 2002, 66(4):041701.
ZHANG P M, DUAN Y S, ZHANG H. Knotlike χ disclinations in the cholesteric liquid crystals[J]. Physica A:Statistical Mechanics and its Applications , 2006, 370(2):245-250.
GENG J, DONG C, ZHANG L, et al . Electrically addressed and thermally erased cholesteric cells[J]. Applied Physics Letters , 2006, 89(8):081130.