07 Jul 2006
The Swiss manufacturer of superluminescent light-emitting diodes is reaping the benefits of its strategy to develop products for non-telecom applications.
It's less than three years since EXALOS rose from the ruins of Opto Speed, an innovative manufacturer of optoelectronic components that went bankrupt during the telecom bust. At the time, the prospects for Opto Speed's two main product lines - superluminescent light-emitting diodes (SLEDs) and photodiodes for optical communications systems - looked distinctly precarious, but the management team took the risky decision to form two new companies, EXALOS and Albis, to continue product development and manufacture.
Three years on, and that decision appears to have paid off. EXALOS has just moved its corporate HQ to a new, more spacious manufacturing facility, and reports that revenues for the past six months alone are already double that for the company's previous fiscal year. Christian Vélez, EXALOS CEO, declined to give specific sales figures, but told optics.org that short-wavelength (800 nm) SLEDs for fiber-optic gyroscopes and medical imaging have accounted for most of the recent revenue growth.
"Although SLEDs have been discussed in the literature for may years, it is only recently that devices with high output power, smooth emission spectra and large bandwidth have been demonstrated and made available in large quantities from vendors like EXALOS," said Vélez.
Since founding the company in 2003, Vélez has sought to avoid the pitfalls caused by developing products focused on only one market area. Instead, EXALOS has developed SLEDs operating at 1300 and 1550 m for datacom and telecom applications, while 800 nm versions have been introduced for fiber-optic gyroscopes, which are used in aerospace and navigation applications, and medical imaging using optical coherence tomography (OCT).
According to Vélez, SLEDs are ideal for these applications because they combine broadband light emission with high output powers. "SLEDs typically have single-mode output powers of the same order of magnitude as single-mode laser diodes - in other words, several tens of milliWatts when biased with several tens of milliamps."
SLEDs also possess the same spatial coherence as a laser diode, which translates into a small beam divergence. This means that light from an SLED can be coupled into an optical fiber with an efficiency of about 50%, which is about the same as for laser diodes.
Unlike laser diodes, however, SLEDs are temporally incoherent. "The large optical bandwidth is a great advantage in applications where interference can cause problems like speckle or ghost signals," commented Vélez. In OCT, for example, SLEDs can suppress second coherence peaks that can degrade the image.
According to Vélez, the extra manufacturing space at its new HQ will be used for testing, reliability assurance and subsystems assembly. And, given the recent sales growth enjoyed by the company, it comes as no surprise that EXALOS plans to further develop its products for the OCT and fiber-optic gyroscope markets.