Uniphase Shares Blue Laser Patents

Stephanie A. Weiss

SANTA CLARA, Calif. -- Biotechnology, semiconductor inspection and optical data storage are among the potential beneficiaries of a friendly agreement that allows Coherent to use some Stanford University patents in a new generation of compact blue lasers.
Uniphase had an exclusive license to use the patents, which cover intracavity frequency doubling of neodymium-doped lasers from the near-infrared (870 to 960 nm) to the blue and blue-green (435 to 480 nm). It has now agreed to sublicense the technology to Coherent; neither company would discuss the agreement's terms.
"Our reason for doing this is that we have an interest to propagate the technology both as a licensee and also in order to grow the market," said Lindsay Austin, Uniphase director of sales and marketing. "OEM customers would like to have more than one credible source."
Blue and green light are a major technology goal for laser manufacturers because they want to create compact solutions that can replace older, bulkier gas laser technologies in some significant scientific and industrial markets.
The reason it's the holy grail is that it's one of the key wavelengths of an argon-ion laser," according to Mark Gitin, Coherent's product manager for diode-pumped solid-state laser products.
The argon-ion laser is a scientific workhorse, especially in biological and chemical analysis, because of the dyes that have been developed to fluoresce under its illumination. However, high-power versions provide utility challenges (i.e., cooling water and power hook-ups) that stymie efforts to use them in creating compact, facile instruments. Other applications include semiconductor inspection, where shorter wavelengths can probe smaller features.

Development will take time

Diode-pumped solid-state lasers are already encroaching on argon-ion's strong green (514-nm) line by internally and externally doubling neodymium-doped crystals' fundamental 1064-nm wavelength. Working without external cooling water and with standard 110-V electrical utilities, these lasers enable many applications that ion lasers cannot address.
Coherent estimates the market for blue and blue-green lasers at tens of millions of dollars per year, but the devices are far from commercialization. "It's going to be some time before we have products," Gitin said.
Austin said Coherent's sublicense is general but Uniphase is willing to grant additional sublicenses for specific application areas.