LightTouch Gadgets: Extending Interactions on Capacitive Touchscreens by Converting Light Emission to Touch Inputs
Proceedings of the 2021 CHI Conference on Human Factors in Computing Systems, 2021•dl.acm.org
We present LightTouch, a 3D-printed passive gadget to enhance touch interactions on
unmodified capacitive touchscreens. The LightTouch gadgets simulate finger 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 …
unmodified capacitive touchscreens. The LightTouch gadgets simulate finger 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 …
We present LightTouch, a 3D-printed passive gadget to enhance touch interactions on unmodified capacitive touchscreens. The LightTouch gadgets simulate finger 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 finger contact on the conductive part nor the use of batteries. As such, it opens up new possibilities for touchscreen interactions beyond the simple automation of touch inputs, such as establishing a communication channel between devices, enhancing the trackability of tangibles, and inter-application operations.
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