I. Introduction
The rapid development of portable electronics such as digital cameras, portable video players, personal digital assistants and mobile phones generates a growing demand for displays with low power consumption and good outdoor and indoor readability. The transflective liquid crystal displays (TR-LCDs) are promising candidates to meet these requirements [1]–[3]. A TR-LCD consists of two sub-pixels of the transmissive (T) and reflective (R) regions. T-mode uses backlight while R-mode uses ambient light to readout the displayed images.