March 17, 2022
Toshiba Corporation has announced a new laser projector unit for its lidar, shrinking the size of the unit by 25% from its previous version, released in June 2021. The new unit is just 206 cubic cm in volume, and can fit in the palm of the hand. The range has been pushed to 300m, with an image resolution of 1,200 by 84 pixels. Toshiba said it can be configured with flexible combinations of projector units to handle several long-range and wide-angle detection applications.
Toshiba said the new lidar will advance progress in the company’s focus application areas, such as autonomous driving and infrastructure monitoring, but also opens the way to exploring partnerships in robotics, drones, and small security devices.
The company said there has always been a tradeoff in lidar range and size against the requirement of an eye-safe laser. “To extend the range of a laser emitted by a single projector, you have to increase its intensity,” said Akihide Sai, a senior research scientist at Toshiba’s Corporate Research & Development Center. “If you do that, you also have to increase its emission width, to avoid a beam that focuses on a small spot and is strong enough to impair eyesight. The problem is, a wider emission requires a larger projector.”
Toshiba said its solution is a lidar that can use multiple small projector units, the laser beam source. They all emit an eye-safe beam in the same direction, which then increases the effective range. This approach also keeps the lidar’s overall size down.
In order to shrink the volume of the projector to 71 cubic cm, Toshiba created an innovative circuit design that reduced the motor control board by 60% against the size of the previous prototype, and using know-how in 3D component mounting to reposition components and lenses. Toshiba said the development team also utilized the company’s proprietary motor control technology to come up with a triple control loop fro the rotation speed, rotation angle and current of the polygonal mirrors in multiple projectors. This helps secure accuracy synchronization, and the deviation angle of the mirrors is only 0.02 degrees or less, Toshiba said.
In field tests, Toshiba confirmed that a lidar with two of the new projectors has a 300-meter range, 1.5 times further than its previous prototype with a single projector. In very bright sunlight, 100,000 lux, the two-projector lidar system also showed more detail in the scanned image than its predecessor, Toshiba said.
“We are continuing research work that will advance our lidar technology, including solid-state lidar, toward boosting range and resolution, and making the lidar even smaller,” said Sai. “We aim to commercialize lidar for autonomous driving and infrastructure monitoring in fiscal year 2023, and look forward to exploring new applications in robots, drones, and security devices.”
For more details on the technology, visit this Toshiba website.