Development of testing system for the stability of organic light emitting devices

A novel testing system for stability of organic light emitting devices (OLED) is proposed to improve the circuital complexity and high cost of existing systems. The proposed system employs the high precision IC operational amplifiers to achieve driving power supply, and uses silicon photocells to capture brightness of OLED. Then an acquisition board based on PCI bus is used to obtain the data concerning the variation of brightness and voltage of OLED. The testing system can provide two different power sources, i. e. , a constant current source and a hybrid current-voltage source (a constant current source for direct bias and a constant voltage source for reverse bias). Silicon photocells are used to replace traditional brightness photometers so that costs are substantially reduced, while the use of the acquisition board based on PCI bus decreases development difficulty and shortens the development time. Testing results show that the system is competent to measure luminance delay and voltage raising, and is stable and reliable.