Ohmic-Sticker Dramatically Extends the Capabilities of Your Touchscreens and Touchpads

It’s obvious that we’re moving away from input devices like keyboards and mice, and towards touchscreens and touchpads. Your smartphone, tablet, smartwatch, and more all have touchscreens. Your laptop may have both a touchpad and touchscreen. Those are all intended to pick up the points you’re touching on a two-dimensional plane. Ohmic-Sticker is a passive add-on that dramatically extends those to provide interesting new possibilities.

Capacitive touchscreens—the type of touchscreen you’ll find on most modern devices—are made from layers of glass with an insulator sandwiched inside, which forms a capacitor. When you touch the screen, or even bring your finger close enough to it, you introduce a small electrical field and that can be detected. However, you don’t have to touch the screen directly. You could hold a piece of copper wire between your fingers and touch that to the screen, and it will be detected. Ohmic-Sticker takes advantage of that fact to expand the touchscreen to include additional buttons and controls.

Imagine if you took that copper wire and attached one end to the corner of your smartphones touchscreen. You then wrapped that wire around to the back of your smartphone. Anytime you touch the end of the wire on the back of your phone, it would register as a touch in the corner of the screen. If you had attached multiple wires, each would transmit a touch to the portion of the screen where the other ends are attached. That’s exactly how Ohmic-Sticker works, just in a more sophisticated manner.

Each Ohmic-Sticker is made from a flexible PCB with adhesive on one side. A portion of that flexible PCB has contact points, which are pressed up against the touchscreen where the PCB is attached. Traces connect those contact points to the new control inputs, which can be buttons, touch-sensitive surfaces, or any other kind of typical input. Modern capacitive touchscreens are very sensitive, which means the contact portion of the PCB would only take up a small portion of the screen, but could still yield many additional buttons. Essentially, a tiny contact the size of a few pixels could be expanded into a large button anywhere on the device. Ohmic-Sticker is still in the R&D phase, but skilled makers could reproduce the technology right now.