Tiny gyroscope the size of a grain of rice could help shrink gadgets even further
The electronics inside consumer gadgets are often miniaturized versions of bigger components – like phone cameras, for instance – and that applies to the gyroscopes used to help a device orientate itself in 3D space. Now scientists have worked out a way of making these gyroscopes much, much smaller.
How small? Well, smaller than a grain of rice in fact. If you're hoping your next phone is going to be an easier fit inside your pocket – or even small enough to clip to your wrist – then this is one of the innovations that might help.
"The proof-of-concept device is capable of detecting phase shifts 30 times smaller than state-of-the-art miniature fibre-optic gyroscopes, despite being 500 times smaller in size," explains the team behind the work.
Today's wearables, smartphones, and drones use microelectromechanical (MEMS) sensors as gyroscopes, to work out how they are being rotated: it's how your phone knows to switch from portrait to landscape mode when you turn it around.
These electronic gyroscopes are much smaller than the rotating, nested wheels that made up the first models, but they're not always as accurate as they could be. That's led to the development of optical gyroscopes that use a split beam of light to get their bearings – what's known as the Sagnac effect.
While optical gyroscopes improve accuracy, up until now they haven't been any smaller than a golf ball. That brings us to the new research from scientists from the California Institute of Technology (Caltech), who have used a technique they call "reciprocal sensitivity enhancement" to make optical gyroscopes substantially smaller.
The Sagnac effect works by detecting very slight variations in the two beams of light split from a single source: those differences can be decoded by the gyroscope to judge rotation and orientation. The trick that the researchers have pulled off is to weed out some of the noise from these signals while maintaining the variations essential to the Sagnac effect (so "reciprocal" in affecting both light beams together).
That reduced noise – or "sensitivity enhancement" – means the whole system can work with weaker signals, and that means everything can be shrunk right down. The work has been published in Nature Photonics.
As is the case with any research of this type, it's going to take a long time for the technology to make its way from the laboratory to a gadget being sold on the shelves of your local electronics store, but now you know what's in the pipeline: super-small gyroscopes that are more accurate than ever before.