Pixel driver circuit for organic light emitting device

摘要

A pixel current driver comprises a plurality of thin film transistors (TFTs) each having dual gates and for driving OLED layers. A top gate of the dual gates is formed between a source and a drain of each of the thin film transistors, to thereby minimize parasitic capacitance. The top gate is grounded or electrically tied to a bottom gate. The plurality of thin film transistors may be two thin film transistors formed in voltage-programmed manner or five thin film transistors formed in a current-programmed ”V T -compensated manner. Other versions of the current-programmed circuit with different numbers of thin film transistors are also presented that compensate for ´V T . The OLED layer are continuous and vertically stacked on the plurality of thin film transistors to provide an aperture ratio close to 100%.