Jeonbuk National University (JBNU) (President Yang O-bong) Research Professor Kim Minsu of Professor Seunghee Lee's research team (Graduate School, Department of Nano Convergence Engineering, College of Engineering; Department of Polymer -Nano Science &Technology, College of Engineering) has succeeded in developing the first ultralow-power flicker-free 1Hz-driven FFS-LCD. 

For liquid crystal displays (LCDs), power consumption decreases linearly as the driving frequency is lowered. However, when driven at low frequencies below 30Hz to reduce power consumption, the flexoelectric effect occurs in nematic liquid crystals. This causes flicker—where brightness varies by the position of driving electrodes within a pixel and over time—leading to image quality degradation. For this reason, the low-frequency, low-power driving method has not been commercialized.

As a result, displays have been unable to realize potential energy savings, preventing a fundamental approach to the global energy challenges that have emerged worldwide. 

To address this, the team clarified the mechanism by which the flexoelectric effect occurs in nematic LCDs and, in collaboration with display industry specialists LG Display Co., Ltd. and Merck Performance Materials Ltd., developed molecular structures that maintain uniform brightness regardless of the flexoelectric effect and manufactured a prototype. 

The developed prototype laptop display (13.4-inch WUXGA) operated successfully with no image quality degradation for static images at 1Hz and for video playback at 10Hz. Compared with a 60Hz-driven LCD, power consumption decreased by approximately 83% at 1Hz and by about 47% at 10Hz, demonstrating performance suitable for energy-saving display systems. 

An additional notable point is that the team proposed an indirect but much simpler method than previous approaches for determining the flexoelectric coefficients. Predicting the intrinsic flexoelectric coefficients of each liquid crystal molecule is a critical element for developing this technology, making this a highly significant result. 

The flexoelectric coefficient is closely related to the flexoelectric effect, and various measurement methods have been proposed previously. However, these methods are difficult and prone to large measurement errors; thus, even reported coefficients for the same materials have often varied across papers, reducing their practical utility.

To overcome this, the team analyzed electro-optical measurements according to differences in flexoelectric coefficients between liquid crystals and matched experimental and simulation values to determine the contribution of coefficient differences to the flexoelectric-optical effect. 

Research Professor Kim Minsu stated, "By enabling the inference of two types of differences in flexoelectric coefficients, a foundation has been laid to propose molecular structures that can prevent image quality degradation caused by the flexoelectric effect. Through this, we expect to make a significant contribution to reducing LCD power consumption." 

The study involved Research Professor Kim Minsu; Da-yeon Lee, M.S. (graduate); Hanbyeol Park, M.S. (graduate); and master's student Ha-young Jeong. LG Display Co., Ltd. and Merck Performance Materials Ltd. conducted the collaborative research. The research was published in the latest issue of the international journal in optical materials, Advanced Optical Materials (IF=9.0), under the title "Ultralow Power Consumption Liquid Crystal Display Retaining Superior Image Qualities."

This work was carried out with support from the National Research Foundation of Korea (Creative Challenge Research Base Support Project; Mid-Career Researcher Support Project), the Ministry of Education's BK21-FOUR program, and support from LG Display Co., Ltd. and Merck Performance Materials Ltd.