Electro-Optical Characteristics of the pseudo-PI Vertical Alignment Copolymer Films for Liquid Crystal Device

• Main Authors: Pei-shiuan tsai, 蔡佩璇
• Other Authors: Jiunn-yih Lee
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/79923264764336729323

碩士 === 國立臺灣科技大學 === 高分子系 === 98 === The purpose of this study is to develop a pseudo-PI vertical alignment (VA) copolymer films which is non-contact photoalignment method for liquid crystal (LC) devices. We used the LC/photocurable monomer phase separation technique and mixed negative dielectric anisotropy (N-type) LC, alkyl long carbon chain acrylic monomer, two kinds of the different length for biphenol main chain type acrylic monomer and a photoinitiator were mixed in the proper ratio; Only Ultra-Violet (UV) light irradiation was required to aid the phase separation of the LC mixture system to form the double layers of a VA copolymer film. As for the different length main chain type acrylic monomers structure for the LC molecules and the different cell gap under the VA mode, such as optical transmittance, contrast ratio and response time etc., have been characterized. The result of this experiment was discovered change in the different length main chain type acrylic monomers can improve the electro-optical properties of LC devices and under the proper ratio LC mixture system, the contrast ratio reaching 2028:1. This novel VA technology for the liquid crystal displays (LCDs) industry enables the shortening of Polyimide (PI) pre-processing and we hope to use the photoalignment technique to manufacture excellence electro-optical characteristics and low cost of the LC devices.