Macsimumnews reports on a recently published patent application for "Resolution Independent User Interface Design". Resolution Independence has been described by Apple as a feature for the upcoming version of Mac OS X 10.5 (Leopard). The reasoning is described:
The old assumption that displays are 72dpi has been rendered obsolete by advances in display technology. Macs now ship with displays that sport native resolutions of 100dpi or better. Furthermore, the number of pixels per inch will continue to increase dramatically over the next few years. This will make displays crisper and smoother, but it also means that interfaces that are pixel-based will shrink to the point of being unusable. The solution is to remove the 72dpi assumption that has been the norm.
According to the patent application, traditional user interface designs are created for specific resolutions. In order to support arbitrary resolutions, images have to be up or down-scaled which may introduce blurring or artifacting. They propose a method to describe the user interface objects in a "procedural" and resolution independent manner.