Display is the most power-hungry component in electronics industry. Power-efficient design is strongly required in thin film transistor liquid-crystal display (TFT-LCD) portable products. This work proposes a unified parameterization technique for modeling and multi-objective optimization of TFT-LCD panel using a two-stage response surface model (RSM) and genetic algorithm (GA). To achieve designing specification in circuit and system levels with minimal power consumption simultaneously, a power-delay product is considered as the object function of the TFT-LCD panel optimization. Simulation-validated RSMs and GA are thus implemented into a unified optimization framework for the design optimization problem. Comparing with the conventional design flow using CAD tools, a 21.5% reduction in the power-delay of TFT-LCD panel is achieved with 95% accuracy. Moreover, the time required for the optimization process is significantly reduced by 288 times. We notice that the proposed unified parameterization technique is object flexible and can further optimize the multi-objective system performances (i.e. crosstalk, leakage current, brightness, etc.). The unified parameterization framework may benefit the high performance display panel design in the photonics industry.