Design and Development of Next-Generation Mini Led Driving Structures and Pixel Circuits

The goal of this project is to utilize Mini light-emitting diode (Mini LED) to develop novel backlit modules for liquid crystal displays and pixel circuits for AM Mini LED displays within two years. Compared with organic light-emitting diodes (OLEDs), Mini LEDs provide higher brightness and longer lifetime. Thus, the development of Mini LED for display applications is regarded as an important issue in the future. About the previous project we conducted, eleven Mini LED driving structures for backlit modules are proposed, and eight of them have already been approved by the patent review of AU Optronics. Moreover, five driving structures have been fabricated for feasibility verification and performance evaluation. However, previously proposed circuits using analog driving methods suffers from the decrease in the luminance efficiency of Mini LED when the panel displays are in medium/low grayscales, resulting in the excessive power consumption of backlit modules. Therefore, in the first year of this project, the fabricated glass samples of Mini LED backlit modules proposed in the previous project will be measured and analyzed, including power consumption and brightness uniformity. For further design, a pulse width modulation (PWM) scheme will be implemented to the driving structure as the driving method to ensure the diode operates at the highest luminance efficiency, greatly reducing the power consumption by 10% compared with those of the previous project. Then, 2-3 Mini LED driving structures will be implemented to a 2.89 inch 48×48 backlight for liquid crystal displays. In the second year, the application of Mini LED is transferred from backlight to display. 2-3 Mini LED pixel circuits will be proposed together for patent application. According to the signals used in the proposed pixel circuits, peripheral driving circuits will be designed. Eventually, the proposed pixel and the driving circuit will be integrated into a display with the resolution of 7680×4320 along with pixel circuits to evaluate the feasibility of production, ensuring the error rate of luminance over the whole gray level is within 5%. This project will raise the technique level of the display industry in Taiwan, and the achievements can bring a large number of benefits for the development of Micro LED, economics, and academia in our country.