US Patent 6911964 Frame buffer pixel circuit for liquid crystal display

An enhanced frame buffer pixel circuit with two control transistors and a separate capacitor put in as a memory capacitor before the memory transistor yields a high contrast ratio by removing induced charge and solving a charge sharing problem between the memory capacitor and the liquid crystal display (LCD) capacitor. The memory transistor may be made of either CMOS or PMOS. The frame buffer pixel can be used to drive binary displays which expresses ON and OFF only if a comparator is put in after the pixel electrode circuit to represent gray levels with reduced sub-frame frequency.