This post is required under User eXperience Design, Principles and Concepts; KSU course IAKM 60120. It’s intent is to write a short post about what stuck me most in the previous week.
One of the topics discussed this week that was of particular interest was the importance of understanding human visual acuity in designing software interfaces. Only the center 1% of a person’s total visual field has a high resolution and therefore imparts the most information to the viewer. This area—the fovea—is in contrast to the remaining 99%, which defines a person’s peripheral vision. However, although not as sharply in focus, the peripheral vision area is still important, as it: 1) guides where the fovea should move to, 2) quickly detects motion, and, 3) has a higher acuity in the dark. Of these functions, the first two in particular play important rules in user interface design.
For example, notice the error message in this dialog:
The use of color and an error symbol forces the eye to focus to the upper edge of the form. This color then matches the color change of the labels for the fields of data where the errors occurred. This is an excellent visual guide to the user and indicates how the peripheral areas of vision can be effectively used.
In another example, the dock ribbon at the bottom of a Mac screen is a powerful use of motion in the peripheral vision area:
As the mouse is dragged over the dock, individual icons grow larger and smaller and slide to the left or right. The user’s focus would already been in the area, of course, but the relative movement of the icons makes the process easier and the task far more interesting and is a brilliant interface gadget. (In fact, upon reflection, it is clear that Apple is one up on Microsoft in using movement and sizing more often and more effectively. And that from a die-hard Windows user!)
Understanding how the human visual field works is important because it accommodates the way humans really work and interact with their systems…not the way we (the designers) wish they did. What strikes me most about this topic and the other ideas that are being presented in this UXD course is that the define a truly effective framework for interface evaluation. Prior to this I had vague feelings of why some program interfaces that I had designed worked better than others, but no understanding why. This framework defines guidelines on how to evaluate screen proposals and build better programs…ones that are easier to learn, easier to use and leave the user more satisfied in their work effort.
And that’s a ‘win’ all around!
Thank you for dropping by the Book of Bokeh. I hope you enjoyed this posting as much as I did writing it.
The photo is from a local café. Photograph and comments ©John Etheridge with all rights reserved; not to be used without the expressed written permission of the copyright owner.