optics.org blog

« Interactive exhibits | Main | Auf wiedersehn from Munich »

Research lasers address industrial applications

I found one of the best examples of how laser sources developed for cutting-edge scientific research can drive the commercial optics industry on the Time-Bandwidth booth. The Swiss company, which was set up in 1994 as a spin-off from the ETH Zurich’s ultrafast laser physics group, specializes in producing passively mode-locked lasers that generate femtosecond and picosecond light pulses.

Time-Bandwidth’s Christoph Rüttimann told me that the company’s diode-pumped solid-state lasers were originally developed for research groups to study chemical and molecular processes. But its latest generation of laser modules has also been designed as turn-key solutions for OEM applications such as micromachining, semiconductor processing and medical and life-science diagnostics, where the use of ultrashort pulses enables high peak powers while avoiding thermal damage to the material.

The company’s high-power Fortis laser, for example, can produce laser pulses of less than 800 fs at 1030 nm with a repetition rate of 40—60 MHz and an average output power of 50 W. “This is the most powerful ultrafast oscillator system available on the market,” said Rüttiman. “The oscillator-only, amplifier-free design ensures particularly reliable and stable operation.”

What makes Time-Bandwidth’s lasers different is the use of a semiconductor saturable absorber mirror (SESAM), a mode-locking element that was first invented at ETH Zurich by Ursula Keller. Time-Bandwidth has continued to work with Keller to improve the device design, the fabrication process and the long-term device reliability to produce a laser system that is robust enough for industrial applications.

The company has SESAM device designs that operate at wavelengths ranging from less than 800 nm to more than 1600 nm, pulse widths from femtoseconds to nanoseconds, and power levels from milliwatts up to 50 W. In the Fortis laser, the SESAM is combined with a thin-disk laser to provide clean and transform-limited pulses, while the Duetto laser module incorporates a passively mode-locked seed laser with a diode-pumped amplifier to deliver 12 ps pulses at 1064 nm with a repetition rate of between 50 kHz and 8 MHz.

Posted by Susan Curtis on June 22, 2007 12:26 PM | Permalink