Engineers at the California Institute of Technology have created the world’s smallest fiber optic gyroscope. Five hundred times smaller than a regular gyroscope, this new gyro can fit on a grain of rice. This research breakthrough could lead to more accurate fiber optic gyros compared to mechanical units.
WHAT OPTICAL GYROS DO
Advanced fiber optic navigation technology is critical for aircraft, missiles, unmanned aerial vehicles and ground vehicles. These machines and other platforms depend on fiber optic gyroscopes to operate safely.
HOW THEY DO THEY WORK?
A fiber optic gyroscope detects changes in position or direction using the Sagnac effect. In this way, an optical gyro functions similarly to a mechanical gyro. However, the optical gyro operates by using light passing through a coil of optical fiber.
Inside a typical optical gyroscope, a spooled-up optical fiber carries pulses of laser light. Some pulses move clockwise and others go counterclockwise. The gyro measures rotation by detecting tiny changes in how these pulses arrive at a sensor. Researchers have tried to create smaller optical gyros. However, as the size of the gyro shrinks, the signals from its sensor have grown weaker until they are drowned out by “noise” from scattered light.
WHAT THE TEAM DID
The Cal Tech research team designed a low-noise, photonic gyroscope. They etched light-guiding channels onto a two-square-millimeter silicon chip. These channels guide the light in each direction around a separate circle. This layout keeps scattered light from confusing the device’s sensors. The new design also reverses the light’s direction from time to time. This change helps to cancel out much of the related “noise.”
Optical gyroscopes that use the Sagnac effect to measure rotation could eventually be miniaturized onto nano-photonic platforms. However, thermal fluctuations, component drift and fabrication mismatch often limit the signal-to-noise ratio of these gyros. Because a microscale unit would have a weaker signal, researchers have not yet created an integrated nano-photonic fiber optic gyroscope.
Have you ever wondered how an e-mail reaches your inbox from a co-worker in Europe? Or how a Facebook message gets to you from a cousin in Africa?
The answer lies beneath the ocean. More than 745,000 miles of submarine cables featuring optical fiber make up most of the actual physical internet. These cables wind between and around continents, carrying almost all of our global internet communication.
Recently, the huge amount of data sent between connected smart devices has begun clogging this network of submarine cables, just as interstate highways become jammed with traffic. One way to deal with this massive data growth is to increase the bandwidth capacity of the physical internet. Another way is to create more direct transmission paths between continents.
Taking It Direct
A new project in Finland hopes to use this second method. The plan is to install a new fiber optic cable route across the Arctic Ocean – the only large water body that is really untouched by submarine cables. While melting sea ice raises tremendous concerns for the health of our planet, it presents an entirely new opportunity to install digital links on a straight course between continents.
For data from Asia to reach Europe, it must travel over thousands of cable miles around Asia, up through the Suez Canal and across the Mediterranean Sea into continental Europe. And while this occurs faster than the blink of an eye (about 253 milliseconds), researchers say that data and communication could travel 30 percent faster over a shorter, more direct cable route through the Arctic.
Faster Connections Are Key
Banks and financial trading groups eagerly await faster connections. Traders depend on powerful, low latency networks to buy and sell securities where milliseconds can affect profit and loss. However, big data would also benefit. Today, internet-connected devices outnumber people on the Earth by an almost 3 to 1 margin. And experts predict that internet traffic between Europe and Asia will triple in the next five years.
The deployment of this new cable would actually extend an existing cable route through Finland into Germany. And while a feasibility study by the Government of Finland calls the project a “win-win-win” for Europe, Russia and Asia, there are key areas of concern.
First, constructing this new cable route would cost nearly a billion Euros. Secondly, the icy Arctic terrain and harsh weather conditions would certainly present logistical challenges. And there are always issues involving security. However, a separate cable installation linking Tokyo and London by way of Alaska and Canada is already underway.
Our planet needs more almost supersonic connections. We can expect to see more efforts around the globe to reduce data “pile-ups” and speed the delivery of data and communication.