Focus on 2005: fiber lasers

04 Jan 2005

Our pick of three hot technologies that are set to light up the year ahead - part 2.

The dream

A cost-effective laser that not only displaces incumbent technology in industrial applications, but opens up new markets.

The fiber laser has long been touted as a source offering efficient operation, high-beam quality and maintenance-free running. The big issue now is living up to these expectations.

Cross-section

In the current market, fiber laser development appears to fall into three camps: high-power continuous-wave (CW), pulsed and ultrafast sources. Over the past few years, many companies have emerged and firms such as SPI (UK) and IPG Photonics (US) are now offering kilowatt-class systems for industrial applications.

"The exciting thing is that these companies are now starting to see traction and adoption by the end user," Andrew Brown, Aculight's director of business development told Optics.org. "Fiber lasers can provide multi-kilowatt output with a near-diffraction-limited beam quality, but the technology has to prove itself. We have to be delivering lasers to the end users that make a difference either in terms of better performance, cost or reliability."

The clear goal for fiber lasers is to penetrate industrial applications. However, developers still have some challenges to overcome and issues to think about. Top of this list is cost. Fiber lasers have to be cost-competitive with sources such as the CO₂ laser or the Nd:YAG laser to be adopted by industrial applications where the bottom line is crucial. "It's not just the price of the laser - it's the overall cost over the lifetime of the product," said Brown. "Reduced power consumption and cost of infrastructure are also significant. I think that these will be some of the metrics people will be looking at in the next year."

Fiber manufacture

The pump diodes used in high-power CW fiber lasers account for a significant fraction of the cost of the overall system. Brown believes that improved high-brightness, high-power, lower-cost diodes are a future technology worth investing in.

Another issue is the fibers themselves. All of the high-power CW systems have used ytterbium-doped fibres and emit between 1040 and 1080 nm. According to Brown, continued development of fiber will provide fundamental laser sources at new wavelengths and a means to access additional wavelength regions.

"People are working on 1.5 and 2 µm as well as polarization-maintaining fibres," Brown said. "Aculight has also got CW fibre lasers pumping single frequency tunable multi-watt level sources in the mid-infrared for sensing applications. We have also just recently made 60W of green light."

As more and more applications begin to adopt fiber laser technology and costs begin to fall, 2005 could finally be the year when fiber lasers gain a foothold in industrial applications. "Fiber lasers could take market share away from diode-pumped solid-state lasers," said Brown. "That might be a high repetition rate Q-switched vanadate laser or a tens-of-watts laser for marking applications."

Overall it is likely that 2005 will be a good year for the fiber laser. "There is a lot of room in the market for many other companies," Brown concluded. "I think there are many factors converging, whether it be on the market, technology or commercial front. They are coming together to turn this into something that is real."

Author
Jacqueline Hewett is technology editor on Optics.org and Opto & Laser Europe magazine.