Killer applications for edge-emitting lasers emerge
From 3D lidar sensing to optical communications, France-based analyst, Yole, highlights the key applications that will fuel market growth for EELs in the next five years. Rebecca Pool reports.
By 2024, the market for edge-emitting lasers will have more than doubled to US$5.1 billion, predicts market research & strategy consulting firm, Yole Développement.
Spurred on as always by the optical communications markets, emerging potential killer applications are set to fuel more growth, driving a 13% compound annual growth rate in the next five years.
“EELs can be used as direct lasers, or coupled with optical fibres or crystals to make diode-pumped solid state lasers,” highlights Martin Vallo, technology and market analyst at Yole. “As a result, the number of applications is impressive, including optical communications, material processing, medical,sensing, optical storage [and more].”
“But as the automotive industry head towards an autonomous era, lidar systems for automotive applications are being developed at a fast pace,” he adds. “So 3D lidar sensing is a key emerging killer application.”
According to Yole, right now, the largest market segment for EELs is optical communications, providing a hefty $1.385 million revenue in 2018 and forecast to swell to $3.397 million by 2025.
At the same time, the relatively well-established materials processing and display sectors will provide healthy growth opportunities with markets expected to grow by some $100 million and more, to $533 million and $441 million respectively. Meanwhile, combined printing and optical storage markets will dwindle from $155 million to $53 million.
“The growth rate of optical communications does depend on large Chinese companies such as Huawei and ZTE that produce many laser-based optical systems for datacoms and telecoms,” points out Vallo.
“So optical communications could compensate for decreases in optical data storage,” he adds. “But emerging applications in automotive lidar systems as well as new applications in the medical and materials processing sectors could also compensate here.”
Technology competition
Right now, different EEL technologies, and of course, vertical cavity surface emitting lasers (VCSELs) are available for all market sectors.
For example, in optical communications, 1550 nm, InGaAsP/InP Distributed Feedback (DFB) EELs and 1300 nm, InGaAsP/InGaP Fabry-Perot EELs are typically used at transmission distances between 2 km and 40 km and at up to 40 Gbps. However, 850 nm InGaAs- and AlGaAs-based VCSELs dominate at 60m to 300m transmission distances and lower transmission speeds.
But for the new wave of emerging applications, which technology will be used where? Perhaps not surprisingly, the pathway is not yet clear. For starters, as Vallo points out, the EEL industry is extremely fragmented.
For example, leading players in materials processing sectors, making, say, laser dicers, are vertically integrated so will manufacture EEL devices, laser systems and everything in between. Meanwhile, in upcoming sensing applications, numerous device level challenges mean companies are more specialised and will focus on producing just the EEL device.
“It is going to be difficult to unify the laser diode device market and we do not expect to see any [market] unification coming soon,” says Vallo. “We see plenty of EEL designs for different applications but will carefully watch how the EEL market changes.”
Rising revenues for edge emitting lasers [Yole]
In the meantime, it's no secret that the VCSEL has a head-start in the world of 3D sensing. With a small form-factor, narrow wavelength range and being testable at wafer-level, these devices have already infiltrated consumer applications, most notably in facial recognition, in Apple's iPhone.
However, next-generation, high-end smartphones are set to include rear-facing 3D sensors with ranges up to 5m to detect and measure objects across a room. And this could favour the higher power EEL.
As Vallo puts it: “A huge advantage of the VCSEL is its form-factor and the technology can be easily used for facial recognition in mobile applications, but EELs have potential in rear-3D sensing.”
“It's really a question of whether the power of a VCSEL is enough here or if [manufacturers] will use the EEL instead,” he adds.
And of course, the future looks bright for both VCSELs and EELs in the sensing systems of future autonomous vehicles. Thanks to high efficiency, narrow bandwidth, VCSEL arrays are vying to replace LEDs for in-cabin sensing, to, say, detect and warn a texting driver.
Meanwhile, both VCSELs and EELs could be used for short- to medium-range lidar for blindspot detection, lane departure and rear-collision warning.
“EELs are one hundred times brighter than the VCSEL which will make these lasers more suitable for long-range sensing applications,” says Vallo. “But the VCSEL is a low power device and could save battery power in the future electric car.”
“For each technology, the market share of each application remains questionable and the final integrators will always be considering which is the best option for them,” he adds.
