Patent attributes
The presssure-sensing touch systems and methods employ a light-source system and a detector system operably adjacent respective input and output edges of a waveguide. Pressure at a touch location on the waveguide gives rise to a touch event causes the waveguide to bend or flex. The waveguide bending causes a change in the optical paths of light traveling by FTIR, causing the light distribution in the output light to change. The changes are detected and are used to determine whether a touch event occurred, as well as the time-evolution of the touch event. The changes in the output light can include polarization changes caused by birefringence induced in the waveguide by the applied pressure applied. Various detector configurations are employed for sensing the location and pressure of a touch event.
