Curtin University researchers have developed a new technique to make glass water-repellent ... This could mean clearer windshields in heavy rain, self-cleaning skyscraper windows and solar ...

Less wet-ability equals more surface tension. Rain-X's claim that this product "causes water to bead and slide off on [sic] ...

Maybe water on the glass affects its dielectric constant and ... Some Tesla vehicles can use their cameras to passively detect rain. Also, if you don’t need to sense the glass, it is pretty ...