Visual Design for Tablet PC

Visual Design for Tablet PC

Overview of visual design considerations for the Tablet PC.

To summarize, Microsoft® wants Tablet PC users to be successful, to ensure that they can use natural and efficient pen movements to tap hot spots with satisfactory error rates and movement times. Always remember that tapping a pen can be more difficult than clicking a mouse.

You also want to consider which way users view their screen. Even typical indoor office lighting causes considerable glare and color washout of the LCD. Larger hot spots and obvious feedback are essential.

Although using a pen is similar to using a mouse, actually aiming the pen can be much more difficult. Several factors are important: calibration, parallax, pen position, and positional feedback. When employing a mouse, the user looks at the pointer on the screen. When employing a pen, the user's expectation is that the pen points directly at the desired object. Calibration errors are common because, even with extremely good calibration, some interference causes slight distortions.

Even if the user performs calibration with the pen held perpendicular to the screen so as to remove the error from the parallax, the distance that the protective glass surface is above the screen and the user's viewing angle can affect pointing. In addition, the way in which users hold their pen can also cause pointing errors. When a user is writing, the user often holds the pen at a steep angle to the screen. However, that angle doesn't necessarily indicate at which object the user is pointing. The intended object might be where the pen tip is directly above the screen (remember parallax) or where the extrapolated end of the tip points.

Users also generally hold a pen differently when they point to objects on the screen versus when they write. When pointing, users generally hold the pen closer to the middle of the barrel with a loose, two- or three-finger grip. When writing, they hold the pen in a manner similar to how they hold a pen or pencil when writing. All of this slightly changes the position of the cursor relative to the pen.

Microsoft highly recommends that you minimize display parallax by building larger hot spots and space between the hot spots into your application. In addition, provide feedback to users about the position of the cursor on the screen relative to the pen. Although the hardware manufacturer controls parallax, design your application for situations in which parallax makes pointing difficult. Writing areas should also be sized larger to ensure that user writing is properly contained.

The following sections detail visual design recommendations for Tablet PC applications: