Abstract
As LCD such smart phones and tablets is increased to be used out of doors, it is interested in decreasing of contrast ratios of them. Many works are reported about the influence of lights on LCD and it is cleared that the cell characters are changed by mainly UV light. However, chemical change is scarcely reported because of difficulty of analysis of the cell separately in depth profiling. Micro analysis methods such as infrared micro-spectroscopy (μ-IR) and micro-sampling mass spectrometry (μ-MS) give deep insights of chemical and molecular change of LCD directly. In this paper, it has tried to analyze the LCD component change in a cell after UV treatment dividing the cell cross sectional direction, bulk liquid crystal (LC) layer and interface LC/PI film layer, and investigated the component change of LCD. It is supposed that LC1 is much condensed and gathered at the interface LC/PI alignment film at first, but it is destroyed by UV light spreading to the bulk layer and PI film is caused a little chemical change deducing holding voltage also.
