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This paper proposes a new hydrogenated amorphous silicon thin-film-transistor-based (a-Si:H TFT-based) gate driver circuit that uses the time-division driving method to ameliorate the display-to-touch crosstalk. The proposed work utilizes a recharging circuit to discharge the voltage on the gate node of the driving TFT when the touch sensing starts with the purpose of suppressing the long-term stress of the driving TFT, and charges the gate node of the driving TFT again before the end of the touch-sensing period to enhance the driving capability of the gate driver circuit. Furthermore, the proposed gate driver circuit achieves bidirectional transmission and an adjustable reporting rate of touch sensing. Measurements verify that the threshold voltage shift of the driving TFT is suppressed from 4.8 to 2.9 V after 120 h of stress at 85 °C and the output waveforms of the proposed gate driver circuits are generated correctly with forward transmission, backward transmission, and pausing in different stages. Moreover, the measured output waveforms are stable without distortion after 360 h reliability test at 85 °C. Consequently, the proposed gate driver circuit is suitable for use in 5.46-in full high-definition panels with in-cell touch technology. [ABSTRACT FROM AUTHOR]

This work reviews pixel circuits for blue-phase liquid crystal displays (BPLCDs) and presents two novel pixel circuits for the BPLC. With respect to the high-operating-voltage BPLC, the first developed pixel circuit comprises practical source driver integrated circuits (ICs) and an additional signal with three voltage levels to widen the voltage range from a data line in order to enable the BPLC to achieve high transmittance. For the low-operating-voltage BPLC with a large dielectric anisotropy, the second pixel circuit boosts the gate voltage of the switch thin-film transistor (TFT) to enhance its driving capability to deal with the large equivalent capacitance of the BPLC. Simulation results verify the functions of both new pixel circuits with Full High Definition (FHD, 1920\times1080) resolution and a frame rate of 120 Hz. [ABSTRACT FROM PUBLISHER]

This work proposes a novel pixel circuit based on amorphous indium-gallium-zinc-oxide thin-film transistors (a-IGZO TFTs) for blue-phase liquid crystal displays (BPLCDs) with the in-plane switching (IPS) mode. The proposed pixel circuit provides a charging current as a constant current source to produce a wide operating voltage range for maximum transmittance of the BPLCs. Based on the simulation results, the proposed pixel circuit supplies a maximum output voltage of 30.14 V with an input voltage swing of 0 V to 9 V generated by the practical source driver integrated circuits (ICs), effectively compensating for the insufficient driving voltage of IPS BPLCDs. [ABSTRACT FROM AUTHOR]

This work presents a new pixel circuit designed on glass by using hydrogenated amorphous silicon (a-Si:H) technology for polymer-stabilized blue-phase liquid crystal (BPLC) display with vertical field switching (VFS) mode. In the VFS mode, the driving voltage of BP-LC can be reduced, moreover, the hysteresis and residual birefringence are effectively suppressed as well. From the simulation results, the average error rate of storage voltage in pixel circuit is below 5.14% while operating frequency is 180 Hz. [ABSTRACT FROM AUTHOR]

We present a new pixel circuit on glass using hydrogenated amorphous silicon (a-Si:H) for driving polymer-stabilized blue-phase liquid crystal displays (BPLCDs). Different from conventional nematics, BPLC demands a large dielectric anisotropy in order to lower the operation voltage. As a result, the pixel's capacitance is increased by \sim\10\times, which seriously limits the charging capability and optical efficiency. Simulation results show that the average error rate of storage voltage in pixel circuit is below 5.14% for 180 Hz operating frequency. [ABSTRACT FROM PUBLISHER]