Fine-grained dynamic voltage scaling on OLED display

Organic Light Emitting Diode (OLED) has emerged as the new generation display technique for mobile multimedia devices. Compared to existing technologies OLEDs are thinner, brighter, lighter, and cheaper. However, OLED panels are still the biggest contributor to the total power consumption of mobile devices. In this work, we proposed a fine-grained dynamic voltage scaling (FDVS) technique to reduce the OLED power. An OLED panel is partitioned into multiple display areas of which the supply voltage is adaptively adjusted based on the displayed content. A DVS-friendly OLED driver design is also proposed to enhance the color accuracy of the OLED pixels at the scaled supply voltage. Our experimental results show that compared to the existing global DVS technique, FDVS technique can achieve 25.9%~43.1% more OLED power saving while maintaining a high image quality measured by Structural Similarity Index (SSIM=0.98). The further analysis shows shat FDVS technology can also effectively reduce the color remapping cost when color compensation is required to improve the image quality of an OLED panel working at a scaled voltage.