Suppressing Gamma Shift at Large Viewing Angles in Liquid Crystal Displays with Dual-Side Electrodes and Small Azimuth Angle Alignment

Gamma shift at large viewing angles is a critical issue in liquid crystal displays, resulting in grayscale distortion and degraded image quality. In this work, a dual-side in-plane switching (DS-IPS) structure with a small initial azimuth angle is proposed to suppress the gamma shift at large viewing angles. Compared with the traditional IPS structure, the proposed DS-IPS structure exhibits more closely distributed V-T curves over various viewing angles. For an electrode width and gap of 2 μm and 4 μm, the maximum gamma shift at a polar angle of 60° decreases from 0.4148 to 0.2922, corresponding to a reduction of 29.6%. Analysis reveals that the dual-side electrodes generate oppositely directed in-plane electric fields near the top and bottom substrates, while the small initial azimuth angle further modifies the spatial LC director distribution. These effects reduce the viewing angle dependence of the optical path difference, thereby suppressing the gamma shift. The proposed method also maintains favorable viewing angle characteristics and exhibits a faster electro-optical response. These results demonstrate that combining dual-side electrodes with small azimuth angle alignment provides an effective approach for suppressing gamma shift at large viewing angles.