Photoalignment development

In this Chapter an overview of the state of the art of liquid crystal applications is given, in particular the current market development for LCD s and the recent developments using non contact alignment techniques like photoalignment and ion-beam alignment. 

There are several developments that could affect LCD technology in the near future. One example is the development of LEDs for use as backlighting for LCDs. By using LEDs rather than a fluorescent bulb, as LCD technology now uses, LCDs can manifest greater contrast in different areas of the screen. Other areas of LCD development include photoalignment and supertwisted nematic (STN) LCDs. 

Chigrinov, Vladimir G., Vladimir M. Kozenkov, and Hoi-Sing Kwok. Photoalignment of Liquid Crystalline Materials. Chichester, England John Wiley Sons, 2008. This book covers some areas of development in improving screens for LCD devices. 

Ushio Ltd. in Japan developed a light source for photoalignment exposure. Its basic configuration is the same as for photolithography. However, photoalignment requires a large exposure area and a polarization element. Ushio s equipment uses... 

With all these new developments in photoalignment technologies, it is now the right time to take an inventory of the progress made over the last 20 years... 

V. G. Chigrinov, V. M. Kozenkov, and H.-S. Kwok, New developments in photoaligning and photo-patterning technologies physics and applications. In Optical Applications of Liquid Crystals, Ed. L. Vicari, Institute of Physics Publishing, Bristol and Philadelphia, 201-244 (2003). 

The stability of LC photoaligning materials was a major concern from the very beginning of their development as LC aligning agents [1], The stable photoaligning materials with respect to UV and IR radiation are photosensitive Pis or crosslink-able materials (see Chapter 2). 

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