Quantitative measurement and control of surface orientation energy of liquid crystal molecule on solid surfaces

点击翻译按钮获取中文摘要

It is important to clarify the surface alignment of liquid crystal on solid surfaces for physical problem as well as for application to devices, and various researches have been done. However, the surface alignment strength or anchoring energy have not yet been clarified. The research of this grant has focused on this problem and the following results have been obtained.1. A method to measure the surface alignment strength (anchoring energy) has been clarified for substrates whose surface is coated with polymer and rubbed with cloth. 2. Effect of the rubbing strength on the anchoring energy has been investigated by using the newly developed method mentioned above. It was clarified from the results that the anchoring energy was directly depending on the rubbing density. In addition, a reliable and accurate method to control the surface energy was established. 3. Effect of surface anchoring energy, which was controlled by the above mentioned method, on molecular alignment of ferroelectric liquid crystal is investigated. From the results, it was succeeded to form the ideal uniform alignment (bookshelf structure) of the ferroelectric liquid crystal by decreasing the anchoring energy lower than a critical value, which enables to realize electro-optical devices with fast response of microsecond order and excellent memory characteristics. 4. Detailed surface physics which dominate the anchoring energy has not yet been clarified. Clarification of this point is an important future subject.