We propose a new technique to extract the steadystate capacitance-voltage (C-V) characteristics of an active-matrix liquid crystal display (AMLCD) using its transient luminance responses. We show how to determine the capacitance of pixels in an AMLCD using the charge conservation law in a pixel and the one-to-one relation between the luminance and capacitance of LC molecules. The C-V data extracted at the ends of the first and second frame times match very well with each other, which confirms that our technique is valid. By using the extracted C-V data, we calculate overdrive voltage values according to transitions. The results show that the overdrive voltages have a linear relation with the transition voltage difference. The linear characteristics can help the overdrive hardware to be extremely simple. The ease of implementation of the overdrive technology with the linear voltage relation should facilitate further adoption and expansion of LCD products with faster response times.