One Stroke Alphanumeric Input Method by Sliding-in and Sliding-out on the Smartwatch Screen

Abstract

We have developed a character input method for smartwatches with circular screen, that allows you to enter one alphanumeric character with a single stroke. With this method, characters are selected by the combination of the start and end positions of the stroke.

On the standby screen, a square inscribed inside the circular display is assigned to the text area. The left, top, and right of the remaining area is split in two, with each segment used as a key. As a result, the key length is longer than the fingertip size of 10 mm. The screen occupancy of the keyboard is 36%.

Each key is selected by slide-in, which is the operation of moving the fingertip that touches the outside of the screen inward. The slide-in ensures that it crosses the edge of the screen, so that passing of the fingertip can be detect with very thin keys. As the fingertip passes the edge of the screen, the screen is separated to 12 areas. Each area is assigned one alphanumeric character or symbol. By moving the fingertip to one area then releasing from the screen, the character assigned to that position is entered.

The key assignment is based on the telephone keyboard. The two keys on the telephone keyboard are combined into one key in our method. As the slide-in passes through a key, the two numbers assigned to the key and the 6 or 7 alphabets associated with those numbers are displayed in each split area.