Interlayer Processing in Active Matrix OLED Displays

Medical genetic

Threshold Voltage Compensation Error in Voltage Programmed AMOLED Displays

A new accurate voltage-programmed pixel circuit for active matrix organic light-emitting diode (AMOLED) displays is presented. Composed of three TFTs and one storage capacitor, the proposed pixel circuit is implemented both in a-Si and a-IGZO TFT technologies for the same pixel size for fair comparison. The simulation result for the a-Si-based design shows that, during a programming time of 90 μs, the pixel circuit was able to compensate for a 3V threshold voltage (Vth) shift of the drive TFT with almost no error. In contrast, the a-IGZO-based pixel circuit, has a larger current error (of around 8%), despite its proven three-fold higher speed.Authors thank to the EPSRC under Project EP/M013650/1

Device-circuit interactions and impact on TFT circuit-system design

This paper reviews the importance of device-circuit interactions (DCI) and its consideration when designing thin film transistor circuits and systems. We examine temperature- and process-induced variations and propose a way to evaluate the maximum achievable intrinsic performance of the TFT. This is aimed at determining when DCI becomes crucial for a specific application. Compensation methods are then reviewed to show examples of how DCI is considered in the design of AMOLED displays. Other designs such as analog front-end and image sensors are also discussed, where alternate circuits should be designed to overcome the limitations of the intrinsic device properties

Threshold Voltage Compensation Error in Voltage Programmed AMOLED Displays

© 2005-2012 IEEE. A new accurate voltage-programmed pixel circuit for active-matrix organic light-emitting diode (AMOLED) displays is presented. Composed of three TFTs and one storage capacitor, the proposed pixel circuit is implemented both in a-Si and a-IGZO TFT technologies for the same pixel size for fair comparison. The simulation result for the a-Si-based design shows that, during a programming time of {\hbox{90}}μ \hbox{s} , the pixel circuit was able to compensate for a 3 V threshold voltage (V\rm th) shift of the drive TFT with almost no error. In contrast, the a-IGZO-based pixel circuit, has a larger current error (of around 8%), despite its proven three-fold higher speed.Authors thank to the EPSRC under Project EP/M013650/1