Augmenting the input space of portable displays using add-on hall-sensor grid

Since handheld and wearable displays are highly mobile, various applications are enabled to enrich our daily life. In addition to displaying high-fidelity information, these devices also support natural and effective user interactions by exploiting the capability of various embedded sensors. Nonetheless, the set of built-in sensors has limitations. Add-on sensor technologies, therefore, are needed. This work chooses to exploit magnetism as an additional channel of user input. The author first explains the reasons of developing the add-on magnetic field sensing technology based on neodymium magnets and the analog Hall-sensor grid. Then, the augmented input space is showcased through two instances. 1) For handheld displays, the sensor extends the object tracking capability to the near-surface 3D space by simply attaching it to the back of devices. 2) For wearable displays, the sensor enables private and rich-haptic 2D input by wearing it on user's fingernails. Limitations and possible research directions of this approach are highlighted in the end of paper.