You may have read or heard advertising executives talk about how many eyeballs their ads are attracting, but Web page views don't really measure the impression that advertising is making upon people. There's no reliable way to tell how long someone looks at an ad, or the sort of impression that it makes. Or at least there wasn't, until now.
In 2013, Google was awarded a patent for a "gaze tracking system" in which a head-mounted device — presumably part of a computer system with video capabilities, such as Google Glass — would capture everything that the wearer gazes at, with an eye to spotting advertisements. (These either could be ads projected by the wearable computer, or else billboards, signs on bus kiosks, and other physical objects.) The system then would record how long the user looked at each ad, and possibly measure the degree of pupil dilation to determine how much of an emotional response the ad evoked [source: Neven].