Dynamic refresh-rate scaling via frame buffer monitoring for power-aware LCD management

In recent years, there has been wide-spread use of large and high-resolution liquid-crystal displays (LCDs) on handheld devices. The portion of LCD power consumption in the overall system has gradually increased. While most of the previous research on LCD power management has focused on the hardware level, practical mechanisms at the software level are hardly known. This paper presents a power-aware LCD management mechanism, based on dynamic refresh-rate scaling and frame buffer monitoring. The proposed mechanism guarantees the display quality of service, which is inherently specified by content types. The mechanism does not require additional hardware or modifications to applications. The experiment results—on a commercial PDA with a 320 × 240 resolution—show that the proposed mechanisms effectively reduce the power consumption by up to 10%, while satisfying the display quality requirements for the LCD screen. Copyright c © 2006 John Wiley & Sons, Ltd.