A touch panel and an electronic device having the same are provided. In this process, particularly even in polymerizing higher olefin, demineralization is unnecessary. Areal densities of successive layers are determined by self-consistent solution of equations relating the ratios of intensities of the characteristic fluorescence lines of successive elements. The flexible body may further be tensioned across the stiffening insert. The user interface system of the preferred embodiments has been specifically designed to be incorporated into an electronic device, such as the display of a mobile phone, but may be incorporated in any suitable device that interfaces with a user in both a visual and tactile manner.