Amorphous IGZO TFT-Based Pixel Buffer to Suppress Blue-Phase Liquid Crystal High-Frequency Effect

This letter discusses the frequency effect of polymer-stabilized blue-phase liquid crystal (BPLC) on the data voltages of a conventional pixel circuit and develops a new pixel buffer that exploits amorphous indium–gallium–zinc-oxide thin-film transistors (TFTs). During high-speed operations, BPLC seriously distorts data voltages because of the highly frequency-dependent dielectric anisotropy. To lessen the frequency-dependent effect of BPLC, a source-follower structure is integrated into the proposed pixel buffer to prolong the charging time of the BPLC cell. The experimental results show that the source-follower yields linear output characteristics. Further compensation for TFT
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shifts and suppressing the leakage current are confirmed to make the data voltages on the BPLC cell highly uniform and stable.