Though most everyone in the audience left Minority Report with the precrime scrubber interface burned into their minds (see Chapter 5 of the book for more on that interface), the film was loaded with lots of other interfaces to consider, not the least of which were the wearable devices.
Precrime forearm devices
These devices are worn when Anderton is in his field uniform while on duty, and are built into the material across the left forearm. On the anterior side just at the wrist is a microphone for communications with dispatch and other officers. By simply raising that side of his forearm near his mouth, Anderton opens the channel for communication. (See the image above.)
There is also a basic circular display in the middle of the posterior left forearm that displays a countdown for the current mission: The time remaining before the crime that was predicted to occur should take place. The text is large white characters against a dark background. Although the translucency provides some visual challenge to the noisy background of the watch (what is that in there, a Joule heating coil?), the jump-cut transitions of the seconds ticking by commands the user’s visual attention.
On the anterior forearm there are two visual output devices: one rectangular perpetrator information (and general display?) and one amber-colored circular one we never see up close. In the beginning of the film Anderton has a man pinned to the ground and scans his eyes with a handheld Eyedentiscan device. Through retinal biometrics, the pre-offender’s identity is confirmed and sent to the rectangular display, where Anderton can confirm that the man is a citizen named Howard Marks.
Wearable analysis
Checking these devices against the criteria established in the combadge writeup, it fares well. This is partially because it builds on a century of product evolution for the wristwatch.
It is sartorial, bearing displays that lay flat against the skin connected to soft parts that hold them in place.
They are social, being in a location other people are used to seeing similar technology.
It is easy to access and use for being along the forearm. Placing different kinds of information at different spots of the body means the officer can count on body memory to access particular data, e.g. Perp info is anterior middle forearm. That saves him the cognitive load of managing modes on the device.
The display size for this rectangle is smallish considering the amount of data being displayed, but being on the forearm means that Anderton can adjust its apparent size by bringing it closer or farther from his face. (Though we see no evidence of this in the film, it would be cool if the amount of information changed based on distance-to-the-observer’s face. Writing that distanceFromFace() algorithm might be tricky though.)
There might be some question about accidental activation, since Anderton could be shooting the breeze with his buddies while scratching his nose and mistakenly send a dirty joke to a dispatcher, but this seems like an unlikely and uncommon enough occurrence to simply not worry about it.
Using voice as the input is cinegenic, but especially in his line of work a subvocalization input would keep him more quiet—and therefore safer— in the field. Still, voice inputs are fast and intuitive, making for fairly apposite I/O. Ideally he might have some haptic augmentation of the countdown, and audio augmentation of the info so Anderton wouldn’t have to pull his arm and attention away from the perpetrator, but as long as the information is glanceable and Anderton is merely confirming data (rather than new information), recognition is a fast enough cognitive process that this isn’t too much of a problem.
All in all, not bad for a “throwaway” wearable technology.