Going on a date can be a nightmare for the best of us.

But now a pair of 'social X-Ray' glasses promises to tell you exactly what the other person is thinking - and when you should stop talking.

The glasses have a built-in camera which monitors the other person's facial expressions and matches them up with 24 known features which convey emotions.

It will then tell the individual via an earpiece and lights on the glasses what their date is thinking.

In a traffic light-style system, a red light means negative, amber means they are moderately interested and green means your date is happy.

The glasses are currently under development by researchers at the Massachusetts Institute of Technology's Media Lab.

They say that wearing them during a conversation with another person is like having an 'extra sense' that they are bored or losing interest.

The eyewear was developed for people suffering from autism who have genuine difficulties interacting with others, but now the team behind it has seen wider applications.

The prototype works thanks to a camera the size of a grain of rice which is put into the glasses frame and connected via a wire to a small computer which can be attached to the user's body.

The camera monitors how long and how often 24 'feature points' appear on the subject's face which are then analysed by software developed by the MIT team.

This data is then compared with a bank of expressions and the computer tells the wearer what is going on via the earpiece and the traffic light system.

So far the glasses are still a work in progress and have been accurate just 64 per cent of the time, a figure which is expected to improve with further tests.

(Read by Nelly Min. Nelly Min is a journalist at the China Daily Website.)