Lighttouch gadgets: Extending interactions on capacitive touchscreens by converting light emission to touch inputs

Abstract

We present LightTouch, a 3D-printed passive gadget to enhance touch interactions on unmodifed capacitive touchscreens. The LightTouch gadgets simulate fnger operations such as tapping, swiping, and multi-touch gestures by means of conductive materials and light-dependent resistors (LDR) embedded in the object. The touchscreen emits visible light and the LDR senses the level of this light, which changes its resistance value. By controlling the screen brightness, it intentionally connects or disconnects the path between the GND and the touchscreen, thus allowing the touch inputs to be controlled. In contrast to conventional physical extensions for touchscreens, our technique requires neither continuous fnger contact on the conductive part nor the use of batteries. As such, it opens up new possibilities for touchscreen