A Desktop User Interface That Fitts

One of the problems with the Microsoft Windows user interface is the fact that the menu bar is attached to the top of the active window.  When you move your mouse to the the menu, there is the potential that you can overshoot the menu and must move your mouse back.  This increases the amount of time necessary to use the menu.

Apple addresses this issue by putting the menu bar at the top of the page.  This makes it impossible to overshoot the menu and speeds up activity.  Bruce Tognazzini wrote about this issue in an excellent article titled, “A Quiz Designed to Give You Fitts”.  In the article, Bruce writes about Fitts' Law that states, "The time to acquire a target is a function of the distance to and size of the target."  Anchoring the menu bar at the top of the screen creates an infinity large target which is in line with Fitts Law.  The problem is, that there is still a distance between the active window and the menu bar that must be crossed which slows users down.  Refer to the Dead Space in the picture below.

A better solution would be to use the same backstop that Apple uses but decrease the distance the mouse must travel to reach the menu bar.  A backstop should be placed at the top of the active window to prevent the mouse from moving beyond the the menu bar at the top of the window.  This would increase the effective area of the target while decreasing the distance traveled by the mouse.  If a user wanted to access another window, they could move the mouse to the left, right or bottom of the active window to escape.  A user could also use Alt Tab, a key combination that can be accessed by the left hand that usually does not access the mouse.

When the mouse hit the backstop, it would stop and only slide from left to right. If a user continued to push the mouse past the backstop, the pointer would eventually be released and could continue to move across the desktop.

By creating a local backstop at the top of the active window, Fitts law states that the time required to access a menu should be faster compared to both the Microsoft Windows and the Apple Macintosh interface.  This will increase the productivity of anyone who routinely accesses menus such as graphic designers and will also make life easier for people such as seniors who may have poor hand eye coordination.