38.1: Optical Feedback for AMOLED Display Compensation using LTPS and a-Si:H Technologies

New optical feedback pixel circuits for a-Si:H and LTPS technologies will be presented. The circuits will enable correction of threshold voltage drift of the drive TFT and degradation of the OLED. In the a-Si:H case this will be achieved with a standard a-Si:H process and for LTPS an a-Si NIP photodiode is integrated. Operation, technology and measurements will be presented.