The smallest high-performance optical gyroscopes available today are bigger than a golf ball and are not suitable for many portable applications
Scientists have developed the world’s smallest optical gyroscope that could find its way into drones and spacecrafts in the future.
Gyroscopes are devices that help vehicles, drones, and wearable and handheld electronic devices know their orientation in three-dimensional space.
The new gyroscope is developed by Caltech engineers led by Ali Hajimiri, Bren Professor of Electrical Engineering and Medical Engineering in the Division of Engineering and Applied Science, reports ScienceDaily.
New gyroscope is smaller than a grain of rice
Smaller than a grain of rice, the new gyroscope from Hajimiri’s lab achieves this improved performance by using a new technique called “reciprocal sensitivity enhancement.”
In this case, “reciprocal” means that it affects both beams of the light inside the gyroscope in the same way. Since the Sagnac effect relies on detecting a difference between the two beams as they travel in opposite directions, it is considered nonreciprocal.
Inside the gyroscope, light travels through miniaturized optical waveguides (small conduits that carry light, that perform the same function as wires do for electricity). Imperfections in the optical path that might affect the beams (for example, thermal fluctuations or light scattering) and any outside interference will affect both beams similarly.
Hajimiri’s team found a way to weed out this reciprocal noise while leaving signals from the Sagnac effect intact. Reciprocal sensitivity enhancement thus improves the signal-to-noise ratio in the system and enables the integration of the optical gyro onto a chip smaller than a grain of rice.