Plessey Semiconductors

Plessey Semiconductors
Information
Industry	Semiconductors, MicroLED displays, optoelectronics
Founded	1956 (semiconductor operations); relaunched as Plessey Semiconductors in 2010
Headquarters	Plymouth, England, United Kingdom
Notable Personnel	David Hayes (CEO), Phil Greenhalgh (CTO), Keith Strickland (former CEO)
Products	MicroLED microdisplays, GaN-on-silicon LEDs
Parent	Haylo Labs (since August 2025)
Website	https://plessey.com

Plessey Semiconductors (also known simply as Plessey) is a British developer and manufacturer of MicroLED displays based in Plymouth, England. It builds monolithic microLED arrays on a gallium nitride on silicon (GaN-on-Si) platform for near-eye microdisplays in augmented reality (AR) and mixed reality glasses, and runs research, process engineering and manufacturing at its Plymouth site. The present company was relaunched in 2010 from the former X-FAB wafer fab in Plymouth, and it moved from LED lighting into microLEDs in the late 2010s.

Plessey's main connection to XR is its work with Facebook (now Meta). In March 2020 it signed a multi-year agreement to dedicate its operations and manufacturing to Facebook's AR and VR prototyping and to grant Facebook an exclusive license to some of its intellectual property. This was a licensing deal, not an acquisition. In January 2025 Plessey and Meta announced a red microLED display for AR glasses that they said reaches up to 6,000,000 nits. In August 2025 the London company Haylo Labs, led by former WaveOptics CEO David Hayes, bought Plessey with a loan from the Chinese electronics manufacturer Goertek.

Reviewed 13 October 2026. Checked every cited source (Plessey site and press releases, Facebook announcement, Information Display, Evertiq, Semiconductor Today, eeNews Europe, Road to VR, MIXED, MicroLED-Info, optics.org, Yicai, The Register, Manufacturing Today) against the history, Facebook/Meta agreement, display specifications and the 2025 Haylo Labs acquisition. About review dates.

History

Origins and relaunch

The company comes out of the semiconductor business of the British electronics group Plessey. Myles Blake, Plessey's business information director, told Information Display in 2018 that its semiconductor work started in 1956, and the 2025 acquisition announcement also gave 1956 as the founding year; the company's own website timeline says the Plessey Semiconductors brand was founded in Swindon in 1957. The same timeline says its high-technology facility in Plymouth was purpose-built in 1985. Over the following decades the business was owned in turn by GEC, Mitel and the German foundry X-FAB.

Around 2009, according to Blake, employees carried out a management buyout of the Plymouth operation from X-FAB and rebranded it as Plessey Semiconductors. Evertiq reported in January 2010 that Plessey Semiconductors had started trading from its wafer fab in Roborough, Plymouth. It had been formed by acquiring the share capital of X-FAB UK Limited and combining it with a design and technology centre in Swindon. Michael LeGoff, the managing director, called the relaunch "a return to our roots".

GaN-on-silicon and LED lighting

On 7 February 2012 Plessey bought CamGaN, a University of Cambridge spin-off formed in 2010 to grow gallium nitride high-brightness LEDs on large silicon substrates instead of sapphire or silicon carbide. Plessey planned to make the LEDs on 6-inch silicon in Plymouth and set up a Plessey Lighting arm to sell them, first to other manufacturers. Blake said in 2018 that the general LED lighting market had become very competitive on price, and that the company's focus had moved to microLEDs built on the same GaN-on-silicon platform.

Move into microLED displays

By late 2018 Plessey was working on two products: a microLED illuminator to replace separate red, green and blue light sources in smart glasses and pico projectors, and a monolithic microLED display array. Blake described a monochrome array of 1,920 by 1,080 pixels with 8-micrometre pixels, bonded to a silicon backplane bought from Jasper Display.

On 14 May 2019 Plessey and Jasper Display Corp. announced that they had bonded Plessey's GaN-on-silicon microLED wafers to Jasper's eSP70 silicon backplane at wafer level. The result was a 1920 by 1080 monochrome display on an 8 µm pixel pitch, which needed more than two million electrical bonds per display. Plessey said such wafer-level bonding between GaN-on-silicon LED wafers and high-density CMOS backplanes had not been achieved before. Earlier that year, in March 2019, Plessey said it had produced native green microLEDs (dominant wavelength 530 nm, full width at half maximum 31 nm) without phosphor or quantum-dot colour conversion.

In May 2019 Vuzix and Plessey announced an exclusive display device design and long-term supply agreement for AR products. Plessey's microLED was meant to replace the separate red, green and blue light sources and optics in front of the waveguide with one self-emitting display. Plessey also partnered with Compound Photonics in October 2019. In February 2020 the two companies reported their first fully addressable microLED display modules, built on Compound Photonics' 1080p backplane with a 3.015 µm pixel pitch, and said samples of a 0.26-inch module were expected by that summer; Plessey bonded the arrays in Plymouth and Compound Photonics packaged the modules in Phoenix, Arizona.

Facebook and Meta agreement

On 30 March 2020 Facebook announced a multi-year agreement under which Plessey would dedicate operations and manufacturing to helping Facebook prototype and develop microLED wafers for possible future AR and VR products, and would grant Facebook an exclusive license to some of its IP. Plessey said in its own statement that it had "decided to work with Facebook to help achieve their vision of the next computing platform centred around people". Road to VR, citing The Information, reported that Facebook had chosen a licensing deal over an outright purchase to avoid regulatory scrutiny, and that Apple had also been interested in buying Plessey.

In July 2023 MIXED, summarizing a report by The Information on Meta's AR glasses plans, wrote that Plessey's microLED displays were said to be part of the technology behind Meta's planned Orion glasses, that Meta had struggled to make the displays bright enough for normal lighting conditions and to reduce defects, and that Meta was still working with Plessey. Meta's Orion prototype glasses, shown in September 2024, use microLED projectors. Plessey's January 2025 announcement mentioned Orion but did not say who made those projectors, and MicroLED-Info noted that Orion had been assumed to use microdisplays from Jade Bird Display.

On 9 January 2025 Plessey and Meta announced a red microLED display for AR glasses that they described as the brightest of its kind, with brightness of up to 6,000,000 nits at what they called high resolution (under 5 µm) and ultra-low power consumption. These are the companies' own figures. Plessey said it was dedicating its manufacturing operations to Meta prototypes and new XR technologies under a long-term commercial agreement. Jason Hartlove, Meta Reality Labs' vice president of display and optics, said the work had "pushed the boundaries of what's previously been possible".

Acquisition by Haylo Labs

Haylo Labs, a London company set up by the venture firm Haylo Ventures, announced on 20 August 2025 that it had acquired Plessey. It said it would invest more than £100 million in the UK over five years to expand Plessey's manufacturing and workforce in Plymouth. At the time Plessey had about 270 staff. The price was not disclosed. Haylo Labs was founded in March 2025 by David Hayes and colleagues. Hayes had been CEO of the Oxford waveguide maker WaveOptics and had overseen its sale to Snap Inc.

The purchase was financed by Goertek. On 8 August 2025 Goertek disclosed that its Hong Kong subsidiary would lend Haylo up to US$100 million for five years, with equity-linked returns, so that Haylo could buy all of Plessey and add capital for microLED equipment and working capital. If Haylo or Plessey is sold or listed during the loan term, Goertek would also receive 25 percent of the sale price or market value. Goertek said the deal would support its AI smart glasses and AR business. The Register reported that the deal closed on 19 August 2025 and that a source said the UK government had approved it after a review under the National Security and Investment Act 2021. optics.org reported that Goertek had also taken a minority stake in Haylo Ventures, and that Plessey's accounts for the 12 months to June 2024 showed a pre-tax profit of £10.5 million on sales of £56 million.

After the deal Hayes became Plessey's CEO, and Keith Strickland, CEO at the time of the sale, moved to chief technology officer. Plessey's leadership page later listed Hayes as CEO and Phil Greenhalgh as chief technical officer. According to Manufacturing Today, Plessey's workforce had grown from about 120 people in 2020 to more than 270, and Haylo planned to double it by 2034.

Products and technology

Plessey's displays are monolithic: the microLED array is grown and processed on a silicon wafer and then bonded to a CMOS backplane wafer that drives each pixel, instead of placing individual LED dies one by one. The company says it designs and builds photonic devices including microLED displays and optical interconnects, and that its integrated Plymouth site covers research, materials science, process engineering and manufacturing. Its timeline lists 2023 as the year it set up semiconductor processing for developing and manufacturing microLEDs. Under Haylo the company has said that its microLED processes and tools can be repurposed to make optical processing units for AI workloads, and that it intends to develop optical computing products.

Date	Milestone	Details
7 February 2012	Acquisition of CamGaN	GaN-on-silicon LED growth technology from the University of Cambridge
March 2019	Native green microLEDs	530 nm dominant wavelength, 31 nm FWHM, no colour conversion
14 May 2019	Bonded full HD microLED display with Jasper Display	1920 by 1080 monochrome, 8 µm pitch, eSP70 backplane
May 2019	Supply agreement with Vuzix	Exclusive display device design and long-term supply agreement for AR products
13 February 2020	Display modules with Compound Photonics	First fully addressable modules; 1080p backplane, 3.015 µm pixel pitch; 0.26-inch samples planned
30 March 2020	Agreement with Facebook	Multi-year manufacturing commitment and exclusive license to some IP
9 January 2025	Red microLED display with Meta	Up to 6,000,000 nits at under 5 µm resolution (company figures)
19-20 August 2025	Acquired by Haylo Labs	Financed by a loan of up to US$100 million from Goertek

XR work

Plessey's microLED work has been aimed mainly at AR glasses, where a bright, small, self-emitting display can feed a waveguide directly. The Vuzix agreement was built on that design idea of one self-emitting display in front of the waveguide in place of separate light sources and optics. Since 2020 Plessey has described its manufacturing operations as dedicated to Meta's prototype work for possible future XR products. The Haylo acquisition announcement named AR and VR, automotive displays, consumer electronics such as headsets and smart glasses, and optical computing as the main sources of expected microLED demand.

See also

• MicroLED
• Microdisplay
• WaveOptics
• Goertek
• Reality Labs