Patent ID: 9024908
Filing Date: 2015-05-05
Classification: G06F

Abstract:
1. An apparatus for use with a touch-sensitive display screen, comprising: one or more button structures formed of an optically clear material, and disposed over the touch-sensitive display screen in an optically clear fluid having an index of refraction substantially equivalent to an index of refraction of at least some of the one or more button structures; a first optically clear elastomeric membrane over the optically clear fluid forming a sealed barrier; and a hysteretic structure formed beneath a button structure and configured to provide a non-linear force response when a force is applied to the button structure through at least the first optically clear elastomeric membrane and the optically clear fluid, the non-linear force response corresponding to increasing resistance provided before the button structure is activated by the force but little to no resistance provided after the button structure is activated by the force, the button structure corresponding to merely one key comprising a letter or a number, where application of additional force to the button structure after the button structure is activated does not activate another key other than the merely one key, the hysteretic structure associated with the button structure and a second button structure.