We have investigated the generation of pretilt angle in nematic liquid crystal (NLC) and electro-optical (EO) characteristics of photo-aligned TN-LCD with polarized ultraviolet (UV) light irradiated on polyimide (PI) surface. It was found that the LC alignment capability increases with increasing the UV light irradiation time. In case of the fact that the polarized UV light of oblique angle of 60° irradiated on PI surface rotated by 90° at 10 min. after being normally irradiated on PI surface at 30 min., the generated pretilt angle of NLC is about 1.5°. Also, we obtained that the pretilt angle in NLC strongly depends on oblique angle and UV light irradiation time. We considered that the pretilt angle of NLC is attributed to the interaction between the LC molecules and the polymer surface due to photo-depolymerization of polymer. Finally, we measured that the EO characteristics of photo-aligned TN-LCD is almost same in comparison to rubbing-aligned TN-LCD.
|Number of pages||14|
|Journal||Molecular Crystals and Liquid Crystals Science and Technology Section A: Molecular Crystals and Liquid Crystals|
|Publication status||Published - 1999|
|Event||Proceedings of the 1998 17th International Liquid Crystal Conference - Strasbourg, France|
Duration: 1998 Jul 19 → 1998 Jul 24
Bibliographical noteFunding Information:
The authors wish to acknowledge H.Fukuro of Nissan Chemical Industries Co.. Ltd. for providing PI materials. This research was supported in part by Non-directed Research Found (01-E-0809),K orea Research Foundation, 1996.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics