Effect of the Size of User Input Area on Task Performance of a Touch Pen

Abstract

In recent years, various computer input devices have been developed with technological advances. A touch pen becomes more popular as a wireless input device for computers, PDAs and mobile phones. Although previous studies on a touch pen mainly focused on its physical characteristics, hand posture, and movement velocity, user input area has been rarely studied. Unlike tablets or pads with their size fixed, a wireless touch pen must set up its size of input area appropriately under normal circumstance or working environments. This study aims to identify the effect of the size of user input area on task performance of a touch pen. In addition to the size of user input area, display size and control-to-response ratio were examined through the experiment where eighteen subjects participated voluntarily. Task completion time, error rates and subject preference as performance measures were obtained from writing and drawing tasks. Through the experiment, appropriate size of user input area was found with respect to display size and control-response ratio. The study is expected to help the designer determine the specification of a touch pen as an input device for digital devices.