about us

We’re building the hardware foundation for next-era computing

We design and build photonic devices and systems that help our customers shape the future of computing.

From microLED displays to optical co-processors and optical interconnects—hardware that makes computing smaller, faster, cooler, more efficient. Technology woven almost invisibly into daily life.

This is a leap from electrons to photons. From familiar limits to new possibilities. Opening new ways for people to live, work and connect.

Who we are

Plessey has been advancing optical technologies for over 70 years.

Our integrated facility in Plymouth, UK, brings together research, intellectual property, materials science, process engineering and manufacturing under one roof.

We serve large-scale technology customers who need breakthrough optical solutions. Companies building the next generation of computing, display and sensing technologies – where proven capability matters more than promises.

Our approach is deliberate. Not disruption for its own sake, but measured progress backed by decades of calculated risk and technical know-how. We’re recognised as an authority in microLED displays, optical computing, and optical interconnects. When major technology companies need innovations that work at scale, they come to us.

Independent spirit, serious intent. We set new paths – tested, proven, scaled. We operate with the confidence that comes from deep expertise and the humility that comes from tackling genuinely hard problems.

Future-minded, firmly grounded. More than seven decades of invention – still moving forward.

The story so far

2025
2023
2019
2012
1995
1987
1985
1957
Welcome Haylo Labs

Haylo Labs acquires Plessey Semiconductors to supercharge UK’s role in the future of AR/VR and optical computing.

Cutting-edge capability

Established state-of-the-art semiconductor processing capability for developing and manufacturing microLEDs.

Going green

Plessey use GaN-on-Si to emit native green. An industry-first.

GaN-onSi technology

Plessey acquire rights to GaN-on-Si technology.

FAB expansion

Opening of FAB8 and a new ballroom cleanroom – the first SMIF-podded FAB in Europe.

A Royal opening

Plessey’s FAB3 cleanroom was officially opened by HRH Prince of Wales.

A new home

Plessey’s high technology facility was purpose built in Plymouth.

Founded

Plessey Semiconductors brand founded in Swindon.

The story so far

2025
2023
2019
2012
1995
1987
1985
1957
Welcome Haylo Labs

Haylo Labs acquires Plessey Semiconductors to supercharge UK’s role in the future of AR/VR and optical computing.

Cutting-edge capability

Established state-of-the-art semiconductor processing capability for developing and manufacturing microLEDs.

Going green

Plessey use GaN-on-Si to emit native green. An industry-first.

GaN-onSi technology

Plessey acquire rights to GaN-on-Si technology.

FAB expansion

Opening of FAB8 and a new ballroom cleanroom – the first SMIF-podded FAB in Europe.

A Royal opening

Plessey’s FAB3 cleanroom was officially opened by HRH Prince of Wales.

A new home

Plessey’s high technology facility was purpose built in Plymouth.

Founded

Plessey Semiconductors brand founded in Swindon.

One operation.
Every stage connected.

End-to-end capability under one roof – from research through volume production.

Our Plymouth facility integrates capabilities that are typically separated across multiple companies and locations. This integration is our competitive advantage. When research scientists, process engineers and production teams work in the same building, iterations happen in days instead of months.

Research and development

III-V semiconductor integration through to prototype development. Our laboratories house epitaxial growth systems, materials characterisation and device fabrication tools.

Intellectual property

Proprietary IP portfolio covering device architecture, fabrication processes and system integration. Built through decades of innovation in optical technologies.

Process engineering

Cleanroom fabrication processes developed and optimised in-house. From wafer processing through device assembly—every step refined for yield and performance.

Manufacturing at scale

Volume production capability with stringent quality control. Processes proven at scale, ready to meet customer demand.

Quality assurance

ISO 9001:2015 certified. Rigorous testing and validation at every stage. Standards maintained, results documented, commitments met.

By controlling every step, we shorten cycles and strengthen every stage. No handoffs. No compromises. Source to signal.

Leadership team

Technical authority, proven results.

Our leadership team brings decades of combined experience in microLED displays, AR systems, semiconductor manufacturing, optical interconnects and technology commercialisation. Engineers, scientists and business leaders who have built photonic devices, scaled production processes and delivered technologies to market.

Grounded in Plymouth. Invested in its future.

Plessey has been part of Plymouth for over 70 years. That history shapes how we operate: in the community, in local schools, and in the standards we hold ourselves to.

We support the communities around us. Plessey is a member of the Improving Lives Plymouth 110 Club, and each year our people choose a charity to get behind. Our employees volunteer, fundraise, and contribute to the local networks that make Plymouth a stronger place to work and live.

We run STEM outreach at schools across the South West, and our apprenticeship and graduate programmes are built from Plymouth outward.

On the environmental side, we source locally where we can, offer free EV charging for cycles and vehicles on site, and look to reduce our manufacturing footprint at every stage.