Contact angles are essential for understanding the properties of surfaces, liquids, and interactions between them. Several methods are used to measure contact angles, among which this study focused on the established sessile drop method and more recent capillary bridge method. In this study, the latter was slightly modified: the capillary bridge was imaged from a top view, and the contact angle was calculated based on the droplet edge thickness. The aim of the research was to compare the two methods and evaluate their comparability, reproducibility, and advantages in contact angle measurements. Measurements were performed using four different liquids on a plasma cleaned glass substrate. Although the measurements obtained with the capillary bridge method did not fully match the results of the sessile drop method, they were reproducible and stable within the method for all four liquids. These deviations were attributed to microscopic surface irregularities and prewetting effects that occur during the fabrication of the capillary bridge sandwich structure. Differences were also observed between various approaches for creating masks for droplet-edge image processing and between different methods for calculating edge thickness. Despite some unresolved issues with the top-view capillary bridge method, it offers important advantages for measuring volatile liquids and very low contact angles. With further improvements in sample preparation and image processing, the method could become suitable for broader industrial applications.
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