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 ${{\text{V}}}_{{\mathrm{TH}}}$ shifts and suppressing the leakage current are confirmed to make the data voltages on the BPLC cell highly uniform and stable.