Laser technology has existed since the mid-20th century, using a focused beam of light to read data and cut matter. Scientists have long known that ultrashort pulse (USP) lasers could do cool things, literally, by cutting without generating heat. Moreover, they've known the lasers' potential to accomplish such delicate tasks as etching semiconductors and killing tumors to detecting and disabling roadside bombs. The technology offers powerful capabilities in a number of application fields: life sciences, defense and security, materials science and manufacturing.

"Traditional [continuous wave (CW)] laser technology can heat, burn and eventually destroy the area round the target," The San Francisco Chronicle recently explained. A CW laser uses a process of linear excitation, generating substantial heat during ablation (removal of material). The generated heat transfers to the area surrounding the target, leading to melting, material reflow or tissue charring.

USP lasers, by contrast, ablate via a non-linear process called multi-photon ionization. Due to the extreme brevity of the light pulses — typically a trillionth of a second — the energy concentrated in the ultrashort pulse produces a peak power large enough to disrupt the atomic bonds of the target material, resulting in electrostatic forces that expel material from the surface. This process happens at a rate such that the energy of the laser goes into vaporizing material before it can be converted to heat and transferred to materials near the target zone.

Simply put, USP lasers work on a quantum level and knock the electrons right out of their orbits, causing the matter to vaporize almost instantly. (The length of time it takes for the laser to work is measured in femtoseconds: a millionth of a billionth of a second.) When the atomic bonds of the target are disrupted, no heat is transferred to the surrounding area. (The San Francisco Chronicle explains in detail how the USP laser works, in Laser Precision, No Heat.)

Despite USP lasers having been of use for a few decades now, they have been too big, too expensive, and too dependent on operator skill to enable development of meaningful commercial products.

It's a niche technology that's been around for about 25 years but has been notoriously difficult to work with.

According to BusinessWeek:

Even in the highly technical world of optoelectronics, lasers that emit ultrashort bursts of energy have largely been the domain of academic dreamers since they were invented in the late 1970s. Unlike conventional lasers found in DVD players, phone networks, and welding shops, USP lasers switch on and off at impossibly high rates — as quickly as once every femtosecond [... .] Those concentrated blasts can obliterate any material by literally knocking electrons out of an atom's neighborhood. That means the lasers can do their job a few atoms at a time if need be, without heating up surrounding material. Since the zapped material is ablated into oblivion, there's nothing to heat up or melt.

Now tiny laser startup Raydiance, Inc. claims to have bridged the technological gap by developing "the world's first fully software-controlled, desktop-size USP laser" — by shrinking a laboratory behemoth down to a desktop Internet appliance that is "plug and play."

Until Raydiance started developing USP lasers, they were extremely large, the size of a warehouse.

According to Wired:

Raydiance's scientists and engineers have been laboring to make them smaller and smaller over the last three years, mostly undercover. The current iteration of the Raydiance laser could fit on your kitchen table and be plugged into a 110-volt outlet.

Plus, a user simply controls the laser from a graphical interface on a laptop. This means researchers with little or no laser experience can spend their time working on application development rather than on tedious fine tuning of the laser before and during every experiment.

This combination of dramatically reduced size (not to mention cost reductions) with integrated software control leads to seemingly limitless research and application possibilities and widespread development of USP laser-based products and services.

Barry Schuler, former CEO of AOL and now of Raydiance, wants to accelerate the migration of USP technology into the real world.

Among applications under development, Raydiance lists cancer treatment, vision correction, cosmetic treatments, nanoscience applications and applications in genomics.

About 25 other USP laser companies exist, most focusing on using the lasers in scientific research.

The field saw a significant application breakthrough in 2005 when the Food and Drug Administration (FDA) approved Intralase's USP laser to perform the first part of LASIK eye surgery — cutting a flap to reveal the cornea. The procedure was previously done only with a knife and was the cause of most LASIK complications. In March, Advanced Medical Optics acquired Intralase for $800 million.

"Bits and blades are all going to be replaced by light," Schuler recently told Wired. In 10 years, he told Wired, the technology will lead to a "smart" power tool that "won't need sharpening and won't cause injuries."

"The hard part is figuring out the ablate frequencies of different forms of matter — the frequencies at which the laser will cut them," he told Wired. For example, "glass molecules are one thing. Cancer cells, on the other hand, are a little more difficult to determine," Wired explained.

Nevertheless, as of June 22, 2007, there were about 12 Raydiance USP units in the field, and the company hopes to have 30 being used by customers by the end of 2007. Schuler plans to lease his laser for $20,000 per month.

Raydiance has just 30 employees and an initial investment of $25 million from venture capital firm Draper Fisher Jurvetson. The California company was recently awarded a multi-million dollar R&D contract from the U.S. Department of the Navy. Under the terms of the contract, Raydiance is developing a high-power version of its commercial "desktop" USP laser for potential use in a variety of defense and homeland security applications.

Resources

Versatile New Laser May Change Surgery, Metallurgy and More
by Kristen Philipkoski and Brandon Keim
Wired, June 22, 2007

Raydiance Labs: The Long Story of a Short Pulse
by Daniel Dumas
Wired, June 22, 2007

Laser Precision, No Heat
by Tom Abate
SFGate.com, June 18, 2007

Is This Really The Next Big Thing?
BusinessWeek, June 4, 2007

Raydiance, Inc.