Dynamic Labels for Physical Buttons - an Overlay for the iPad

Shwetak Patel,

The goal of this project is to combine the superior affordance and feedback of a physical button with the flexibility and software control of a touchscreen soft button. We created a transparent physical button overlay for a capacitive touchscreen (such as the iPad). The top surface of the button is transparent, allowing the label of the button to be changed by simply changing the image on the screen below (as with a soft button). When you press the physical button down, it electrically connects your finger to the surface of the screen, triggering the soft button on the touchscreen underneath. The button is correctly not triggered by simply hovering – e.g. resting your finger on the key without pressing it. This device is completely passive, and requires no external power or other connections.