A magnetically driven pen interface that works both on and around mobile devices has been developed by a student in South Korea.
This interface, called the MagPen, can be used for any type of smartphones and tablet computers so long as they have magnetometers embedded in.
Advised by Professor Kwang-yun Wohn of the Graduate School of Culture Technology (GSCT) at Korea Advanced Institute of Science and Technology (KAIST), Sungjae Hwang, a Ph.D. student, created the MagPen in collaboration with Myung-Wook Ahn, a master's student at the GSCT of KAIST, and Andrea Bianchi, a professor at Sungkyunkwan University.
Almost all mobile devices today provide location-based services, and magnetometers are incorporated in the integrated circuits of smartphones or tablet PCs, functioning as compasses.
Taking advantage of built-in magnetometers, Hwang's team came up with a technology that enabled an input tool for mobile devices such as a capacitive stylus pen to interact more sensitively and effectively with the devices' touch screen.
Text and command entered by a stylus pen are expressed better on the screen of mobile devices than those done by human fingers.
The MagPen utilizes magnetometers equipped with smartphones, thus there is no need to build an additional sensing panel for a touchscreen as well as circuits, communication modules, or batteries for the pen.
With an application installed on smartphones, it senses and analyzes the magnetic field produced by a permanent magnet embedded in a standard capacitive stylus pen.
The MagPen detects the direction at which a stylus pen is pointing; selects colors by dragging the pen across smartphone bezel; identifies pens with different magnetic properties; recognizes pen-spinning gestures; and estimates the finger pressure applied to the pen.
Notably, with its spinning motion, the MagPen expands the scope of input gestures recognized by a stylus pen beyond its existing vocabularies of gestures and techniques such as titling, hovering, and varying pressures.
The tip of the pen switches from a pointer to an eraser and vice versa when spinning. Or, it can choose the thickness of the lines drawn on a screen by spinning.