In this paper, a mathematical model of LCD motion blur is used to measure the magnitude of perceived blur in a sequence displayed on LCD. Subjective quality assessment tests on CRT and LCD displays are described. A difference of visual quality between the two types of displays is observed for sequences with movements. This loss of quality can be predicted from the importance of motion blur measured in the sequences. An estimation of LCD perceived quality can thus be made from CRT perceived quality. Technical solutions to LCD motion blur problem can be evaluated by this mean.