Abstract
A flexible sensor including a polymeric substrate, four polymeric sensor units, a polymeric bump and a plurality of conductive patterns is provided. The polymeric sensor units are embedded in the polymeric substrate, wherein a pair of polymeric sensor units are located on two opposite sides of the polymeric substrate in the first direction, and the other pair of polymeric sensor units are located on two opposite sides of the polymeric substrate in the second direction perpendicular to the first direction. The polymeric bump is disposed on the polymeric substrate and cover the four polymeric sensor units. The conductive patterns are disposed on the polymeric substrate and connected to the corresponding polymeric sensor unit, respectively.