Strain-Aware Performance Evaluation and Correction for OTFT-Based Flexible Displays

Organic thin-film transistors (OTFTs) are widely used in flexible circuits, such as flexible displays, sensor arrays, and radio frequency identification cards (RFIDs), because these technologies offer features such as better flexibility, lower cost, and easy manufacturability using low-temperature fabrication process. This paper develops a procedure that evaluates the performance of flexible displays. Due to their very nature, flexible displays experience significant mechanical strain/stress in the field due to the deformation caused during daily use. These deformations can impact device and circuit performance, potentially causing a loss in functionality. This paper first models the effects of extrinsic strain due to two fundamental deformations modes, bending and twisting. Next, this strain is translated to variations in device mobility, after which analytical models for error analysis in the flexible display are derived based on the rendered image values in each pixel of the display. Finally, two error correction approaches for flexible displays are proposed, based on voltage compensation and flexible clocking.