Highly accurate photonics chips are being developed that could pinpoint smartphone users position with unprecedented precision.
According to a team of researchers at California Institute of Technology (Caltech), development is underway for an ultrasensitive accelerometer that uses laser light to rapidly pick up on tiny motions.
Accelerometers are already used in a number of applications, and increasingly so in consumer electronics, as the technology shrinks to a sufficient size that it can be placed in mobile devices.
Up until now these accelerometers have used electronic circuitry, which is quick and cheap to produce, but could be improved on in terms of sensitivity. Researchers say laser light is much more difficult to interfere with at room, and therefore allows greater accuracy in determining position.
Attempts to use lasers have been made before, but nowhere near the scale needed to be placed on a chip and put in a phone for example.
However the team at Caltech has now managed to produce components that work at the nanoscale required, opening new applications.
So what improvements could this bring? According to the scientists aside from the consumer aspect, such powerful sensors could help in the stabilisation of fighter jets in flight, or in digging down to oil reserves. Unfortunately they also reckon that the a possible use will be to pester shoppers in supermarket aisles, with advertisers able to target consumers with unprecedented accuracy.
Of course it may be some time before shoppers face a deluge of coupons flooding onto their smartphones, as scientists are still working to move the photonics technology onto silicon chips, a problem they have been attempting to solve for some years now.
But if they are successful then it will be possible to track movements with much greater accuracy than GPS could manage, for better or worse.