Blue phases electro-optics

Lee M, Hur S-T, Higuchi H, Song K, Choi S-W, Kikuchi H (2010) Liquid crystalline blue phase I observed for a bent-core molecule and its electro-optical performance. J Mater Chem... 

Kikuchi and coworkers found the rapid electro-optical effect in polymer-stabilized blue phases and presented the major potential of such phases in application to display devices and optical modulation devices [45,46]. Tra-... 

Fig. 17 Temperature dependence of electro-optical response time for the polymer-stabilized blue phases (polymer fraction a = 6.3, 10.5, 15.0 mol %) in the rise process (A) and decay process (B) [46]...

Chirality is also an important aspect of liquid crystals. The introduction of chiral moieties into the chiral smectic phases induces functions such as ferroelectricity and antiferroelectricity. A few of the unconventional chiral liquid crystals are described in Chapter 1. The blue phase is one of the exotic chiral liquid crystalline phases. In Chapter 3, Kikuchi introduces the basic aspects and recent progress in research of the blue phase. Recently, the materials exhibiting the blue phases have attracted attention because significant photonic and electro-optic functions are expected from the materials. 

Sato, M. Yoshizawa, A. Electro-optical switching in a blue phase III exhibited by a chiral liquid crystal oligomer. Adv. Mater. 2007, 19, 4145-4148. 

Both Equations (14.4) and (14.12) can represent the induced birefringence of a blue phase LC, the former using Kerr constant and the latter using the quadratic electro-optic coefficients. Comparing these two equations, we can see that the Kerr constant K is also dependent on the wavelength. It is a constant only at a given wavelength and temperature. 

P. R. Gerber, Electro-optical effects of a small-pitch blue-phase system. Mol. Cryst. Liq. Cryst. 116, 197-206 (1985). 

Z. Ge, S. Gauza, M. Jiao, et al.. Electro-optics of polymer-stabilized blue phase liquid crystal displays, Appl. Phys. Lett. 94, 101104 (2009). 

Then in 2002, the author and coworkers reported that the temperature range of a blue phase could be increased to over 60 K by forming a small amount (7-8 wt%) of polymers in the blue phase the material was named the polymer-stabilized blue phase (Fig. 8.15) [17], The molecular dynamics are not lost in the polymer-stabilized blue phase, and moreover, the electro-optical response is very fast. It is believed that the polymers in the blue phase condense around disclinations and the blue phase is stabilized when the disclinations are thermally stabilized. 

Fig. 8.18 Electro-optical response of polymer-stabilized blue phases. Precursor 1 is an acrylate monomer (11 %), precursor 2 is an acrylate monomer (8 %), precursor 3 is a methacrylate monomer (11 %), and precursor 4 is a methacrylate monomer (8 %). The liquid crystal was provided by JNC. The electrodes were simple interdigitated electrodes with a spacing of 10 mm...

---