A Prototype Link Lens

The concept upon which the link lens is based is the so-called Magic Lens or movable filter [1,27]. Magic lens filters combine an arbitrarily shaped visual field with an operator that changes the presentation of objects within the view field. In the link lens, the view field is bound to the cursor and is sensitive to any anchors that it is passed over. When applied in this way, its two operators, document and link, transform the anchor into views of document meta-data and link QoS. The prototype link lens is shown in Figure 7. The design was evolved from paper-based sketches of possible lens features. These were presented to six subjects who rated them according to perceived usefulness.

Their overall opinion was that the link lens would affect their browsing strategies. With the exception of the document abstract, there was no consensus about which parts of the link lens would be the most useful, but all subjects expressed a desire to be able to choose a subset of meta-data for viewing at one time. Depending on the task being undertaken, the subjects felt that some parts of the link lens could be beneficial to the usability of the system.

We are currently carrying out further testing of several versions of the link lens with groups of Web users. The objectives include evaluating the value to users of the various different kinds of link information. We are also investigating different ways of presenting the information, including enabling users to customise or adapt the link lens to match their needs, and more economical encodings based upon the appearance of the link in the referencing document. A particular emphasis of this work will be to explore how degrees of user experience affect their ability to make use of link information.