Patterned retarder

If crosslinkable materials are used, patterned retardation plates can be realized using the temperature dependence of A . Starting from high An values at low temperature the An for higher temperature can be fixed by photopolymerization up to An = 0 above T. ... 

Several mechanisms of photoalignment reactions have been reported in the literature and hence a variety of photoalignment materials are available for director patterning. For the manufacturing of a patterned retarder applied in a transflective display (Sect. 9.4.2), we have tested two commercially avail-... 

Figure 9.24 shows an example of a temperature patterned retardation foil viewed between crossed polarisers. In this example the transmissive part does not have any birefringence, which is demonstrated in Fig. 9.24b. The black...

A modelhng sthdy by Karman et al. [30] has shown that the combination of multidomain TN LCDs with patterned retardation foils improves the viewing angle properties of LCDs over multidomain LCDs with uniform retardation foils. In such combinations of a patterned LC layer with a patterned retardation layer, the LC layer acts to decrease the gray scale inversion, whereas the retardation layer improves the off-axis contrast. It is of course important to find an optimum in the number of domains in both the LC layer and retardation foil, but also to keep in mind that increasing the complexity of the system will increase the production costs. It will depend on a specific application whether it is a feasible approach. 

A director patterned retarder can be used in a transflective LCD to boost the optical performance and to lower the power consumption. A transflective display is the combination between a reflective and a transmissive display. 

Fig. 9.22. (a) The patterned retarder as a single component coated on top of a colour filter, viewed in between two crossed polarisers and its orientation with respect to the crossed polarisers. (A) Analyser, (P) poteiser, and (R) retarder (a). This orientation represents the orientation as if it is applied in a transflective LCD. 

Figure 9.15 Patterned retarder transflective MTN/TN LCD (a) schematic device configuration and (b) voltage dependent transmittance and reflectance curves. Zhu 2006. Reproduced with permission firom IEEE.

Stereoscopic displays using patterned retarders and polarizing glasses... 

To bring the fantastic cinematic 3-D experience to ordinary family homes, 3-D TVs with patterned retarders have been developed [31,32]. The concept is shown in Figure 16.8. The odd-row pixels of the LCD are designated for left-eye images and even-row pixels for right-eye images. Correspondingly, the strips of the patterned zl/4 retarder, which overlays odd-row... 

H. Kang, S. D. Roh, I. S. Baik, et al., A novel polarizer glasses type 3D displays with a patterned retarder, SID Tech. Digest, 41, 1(2010). 

Figure 5.18 New possibility to obtain a color TN- or STN-LCD, using a photo-patterned retarder [18], Upper basic red, green, and blue colors obtained by the corresponding properly adjusted phase retarders (PRl, PR2, and PR3). Lower one of the possible configurations with TN-LCD, three polarizers (PiUPsjUPs, and double phase retarder (DPR) configuration comprising two phase retarders PRl and PR2, placed at symmetrical angles a with respect to the input (output) polarizer P1HP3. Reproduced from [18], Institute of Physics Publishing, Bristol and Philadelphia, 201-244 (2003)...

Thus for a transflective display, one is always faced with compromises, either in complexity of the design in terms of cell gap and subpixel structures, or in complexity of the driving electronics. The situation becomes easier if in-cell patterned retarders or polarizers can be made. An example of an in-cell retardation film display is shown in Figure 5.23. It can be seen that the effect of different cell... 

M. Schadt, H. Seiberle, A. Schuster, and S. M. Kelly, Photo-generation of linearly polymerized liquid crystal aligning layers comprising novel, integrated optically patterned retarders and color filters. Japanese Journal of Applied Physics 34, 3240 (1995). 

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