Parallel stripe textures

Application of Parallel Stripe Texture and Alternating Polarized Domains (APD) mode [26]... 

Among these modes, (2) DHF mode, (3) twisted FLC mode, (4) monostable FLC mode, (8) CDR mode, (5) the application of Parallel Stripe Texture and (9) the application of the frustoelectric liquid crystalline phase are reviewed below. 

Other quasi-periodic textures have been reported, including birefringent stripes parallel to the flow direction (Gleeson et al. 1992). A low-shear-rate stripe texture observed in PBG solutions can be attributed to roll cells (Larson and Mead 1993), similar to those... 

The typical SBF texture shown in Fig. 7.28 develops when an a.c. electric field (15 V//zm, 10 Hz) is applied during cooling from the isotropic phase down to the smectic A phase and further to the ferroelectric phase. This stripe texture means a periodic modulation of the refractive index perpendicular to the lines, while the lines themselves are parallel to the rubbing direction. The spacing between lines increases with increasing cell gap. These stripes are similar to those observed by Beresnev et al. [128, 129]. They seem to suppress formation of the helix. Bistability transition is observed between two unwound states of the helix which are called, in [154], the field stabilized states. The thickness of the cell should be chosen as optimum dAn = 0.27 //) and an important requirement [103] gives... 

While such behavior can be seen in achiral LC phases, driven by surface constraints as illustrated in Figure 8.11, further characterization of the phase responsible for the minority domains in the B2 banana phases shows this to be the first unequivocal example of a bulk fluid conglomerate. It is worth noting here that the EO behavior of the majority domains is achiral Stripes parallel to the layers switch to a SmA-like focal conic texture, which is identical for both signs of the field, as can be seen in Figure 8.22. This EO behavior very clearly appears achiral when observing the switching in motion. 

The stripe-shaped texture parallel to the rubbing direction is observed due to the formation of periodic undulation of the layer structure (Fig. 6.3.19). In the case that a strong AC voltage is applied, the chevron structure is deformed into the bookshelf structure and the strain occurs. The strain is relaxed by the rotation of the layer direction [55] which forms the periodic layer undulation. 

Fig. 6.3.19 Structure of the stripe-shaped texture parallel to the rubbing direction.

On the other hand, liquid crystalline materials showing the N (Ch)-SmC phase transition form two kinds of domain on transition into the smectic C phase. In each domain, the layer normal rotates at tilt angle 9, from the rubbing direction and the liquid crystalline molecules align parallel to the rubbing direction (Pig. 6.3.19). In most cases, these two kinds of domains are formed at random. However, depending on the liquid crystalline materials, these two kinds of domains are formed in a striped pattern. The size of Pg does not affect the formation of the stripe-shaped texture and the even FLC materials with a small Pg can form the texture. 

Figure 2.12 Special textures arising in theory, (a] Stripes, which attain the Wiener bounds of the maximal and minimal effective slip, if oriented parallel or perpendicular to the pressure gradient, respectively (b) the HS fractal pattern of nested circles, which attains the maximal/minimal slip among all isotropic textures (patched should fill up the whole space, but their number is limited here for clarity) and (c) the Schulgasser and (d) chessboard textures, whose effective slip follows from the phase-interchange theorem (adapted from. ) Abbreviation HS, Hashin-Shtrikman.

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