No abstract

The adsorption and desorption of the ions are closely related to the image sticking of liquid crystal (LC) cells [1]. We made an effort to measure the fixed quantity of ion concentration by measuring the residual DC voltage in LC cell and the surface anchoring energy in PVA cell. To understand the mechanism of image sticking, we studied these adsorption and desorption activation energy [2][3][4][5] and found that the desorption activation energy increases as the surface anchoring energy does, and this relationship is rather universal. This observation led us to a conclusion that smaller anchoring energy is required to reduce the image sticking of LC cells.

We designed a novel mountain‐shaped cell architecture in order to obtain less than 15 ms of tr+tf response time without an overdriving circuit in vertical alignment mode. This structure significantly reduces the tr+tf time of PVA mode by eliminating abnormal motion in the turn‐on process, which is detrimental to rapid switching.

The degree of imidization of polyimide used in VIA and PDL materials is important characteristic because of relationship with life cycles in OLED. During the curing process, a polyimide film optically changes to a negative C‐plate like sheet structure. The more polyimide chains packed closely, the higher out‐of‐plane retardation (Rth) is. In other words, for analyzing retardation properties of polyimide except for imidization ratio, Rth could be a useful analyzing method. In this study, using polyimide formed from different curing temperature and various chemical compositions, relation between Rth and properties of polyimide film was investigated.