Scottish Startup Advances PCSEL-Based Free-Space Optics With Outdoor Tests

Vector Photonics contends PCSELs offer superior beam quality and power over traditional VCSELs

A Scottish startup developing free-space optics completed tests where it used a crystal-based laser to transmit data across one of the country’s most famous rivers.

While traditional optics leverage vertical-cavity surface-emitting lasers (VCSELs), which emit narrow beams of light, Glasgow-based Vector Photonics is developing a new type of surface-emitting laser using photonic crystal surface-emitting lasers (PCSELs).

The startup contends that PCSELs offer improved beam quality compared to VCSELs resulting in high power capabilities with the speed and surface emission of VCSEL-based offerings. PCSELs also allow optics to operate a single-mode output, eliminating the need for complex beam-shaping elements to guide transmissions.

To validate its viewpoint, the team at Vector Photonics teamed up with the Fraunhofer Center for Applied Photonics non-profit to demonstrate PCSEL-based transmissions across the River Clyde.

The efforts saw data transfers of 50 Mb/s over 1,600 feet, which ended up being twice the system spec required for the experiment – though the startup claimed that figure was “well below” what PCSELs can achieve.

“This is a major step forward for Vector Photonics, proving that our technology is a commercial reality in real-world applications,” Vector Photonics CEO Richard Taylor noted in a statement. “We believe that the demo is the most advanced application of a PCSEL to date, advancing it from a technology readiness level (TRL) of 4/5 to 6/7.”

Free space optics, or using light to communicate from one point to another, is a technology area that’s seeing increased interest amid ever-increasing data transmission sizes. The idea sees light-based optics transmit through the free space (or more simply, the open air), instead of traditional means like radio-frequency (RF)-based wireless solutions.

Google spinout Taara, for example, is looking to apply the concept to tackle backhaul capacity and address fiber reach. And researchers at the University of Cambridge recently developed a VCSEL-based array for indoor connectivity, which they claim could potentially halve Wi-Fi energy per bit.

Vector Photonics’ PCSEL-based efforts across the Clyde showed its technology can perform in outdoor environments. Previously, only lab experiments using ideal conditions and simulations have been attempted.

Beyond long-distance data transmissions, the Scottish startup suggests its PCSEL technology could be used in future AI data center infrastructure for things like scale-out as well as Lidar systems and additive manufacturing (aka, 3D printing).