GoKawiilLidar technology uses pulses of infrared light to calculate distances and create detailed 3D maps of the surrounding environment. This allows autonomous vehicles to detect objects in their path and respond quickly. However, conventional lidar sensors are often large and costly, and many rely on moving components that can wear out over time. These limitations make the systems difficult to use in a wider range of settings.
MIT researchers have now developed an approach that could lead to smaller, more durable lidar sensors that operate without any moving parts. Their advance centers on a new silicon-photonics chip, a type of semiconductor device that controls light instead of electrical signals.
Existing lidar systems built with silicon-photonics chips usually have a narrow field of view. As a result, they struggle to scan areas located toward the edges of a scene. Previous attempts to expand this viewing range have often introduced extra noise and reduced measurement accuracy.
The MIT team addressed those problems by creating an array of integrated antennas that greatly limits unwanted crosstalk, which occurs when neighboring antennas interfere with one another. The design allows the chip to scan across a broader field of view while producing less noise than other silicon-photonics-based methods.
A Smaller Lidar System With a Wider View
The advance could support the development of more capable lidar sensors for challenging uses, including autonomous vehicle navigation, aerial mapping, and the monitoring of construction sites.
"The functionality we demonstrated in this work solves a fundamental problem for integrated optical-phased-array technology, enabling future lidar sensors that can achieve significantly higher performance than we could demonstrate previously," says Jelena Notaros, the Robert J. Shillman Career Development Associate Professor of Electrical Engineering and Computer Science (EECS) at MIT, a member of the Research Laboratory of Electronics, and senior author of a paper on this innovation.
The study also includes lead author and EECS graduate student Henry Crawford-Eng, along with EECS graduate students Andres Garcia Coleto, Benjamin M. Mazur, Daniel M. DeSantis, and Tal Sneh. The findings were published recently in Nature Communications.
How Lidar Maps Its Surroundings
Many traditional lidar systems use a large rotating unit to direct light pulses across a scene. When the light strikes nearby objects, it reflects back toward the sensor. The returning signals provide the information needed to reconstruct a detailed map of the environment.
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