Recent years have seen the development of display technology with the transformation from flat to flexible displays. This has led to changes in the typical shape of such displays, and curved displays with constant curvature have been developed recently. As the shape of the display changes, the sophistication of the lamination process for joining a flat and curved window cover glass with a panel substrate also increases, and continuous research and development is required. In this paper, we report the results of our study on the characteristics of resin spreading on flat and curved substrates using optical clear resin. We confirmed the consistency by comparing the results obtained from the theoretical analysis and experiments. These results are expected to be widely used in the lamination and manufacturing technologies for next-generation displays that will evolve in the future.