Google has been granted a set of patents for eye-tracking advertising technology.

The ‘gaze’ technology could detect when a person is looking at an advert – be it online or offline – and infer their emotional response to it.

The tracking technique would be implemented with a head-mounted device – such as Google Glass – which then communicates to a server, allowing Google to create a ‘pay-per-gaze’ system.

This would register whether an individual has looked at an ad before charging the brand, similar to ‘cost-per-click’.

The patent application was filled back in 2011 but has only been approved now. The move could extend Google’s online advertising business into more conventional forms of media, such as newspapers, magazines and outdoor.

Find out more about patents and the approval process with our patents advice.