Blue Lasers Point Way for CD Firms
The compact disc industry is seeing green in the prospects for blue lasers.
Philips Electronics NV, Sony Corp., Toshiba Corp. and others are racing to develop the tiny beams of light for CD players and multimedia computers. They’re betting that blue laser technology will help satiate the demand to store increasing amounts of digital words, sound and pictures.
Blue lasers allow more data to be crammed onto an optical disc. While a current CD holds one album’s worth of music, a blue laser CD could store the complete works of the Beatles, a library of 4,000 books or a digitally recorded home movie.
“There are markets that haven’t even been formed yet,” said Richard Doherty, director of the Envisioneering Group market research firm in Seaford, N.Y.
Imagine carrying around the yellow pages in a coin purse. It’s possible if companies decide to make blue laser discs the size of a silver dollar, Doherty said.
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Scientists say it will be three to five years before the blue lasers are ready for commercial use. By then, the hunger for storage space will be enormous as digital technology moves into everyday use--from taking birthday party photos to watching a rented movie.
“There’s no such thing as enough storage. We can always think of new uses,” said Paul Saffo, an analyst at the Institute for the Future in Menlo Park.
A laser reads a compact disc much like a stylus reads a phonograph record. Instead of the grooves on an LP, an optical disc has pits or valleys. As the disc spins, the laser bounces light off the surface, translating the pits and spaces in between as digital ones and zeros.
Packing data more closely requires lasers that can focus on smaller points. Light beams with short wavelengths have a narrower focus, or point, than those with longer waves. Light waves are shorter at the blue end of the color spectrum, which is why blue lasers are sparking such interest.
A specific type of laser called the semiconductor diode laser is used to read an optical disc. The diodes are the size of an electronic transistor and are made up of thin layers of chemically enhanced film.
Making a semiconductor laser is no easy task. A lot depends on getting finicky chemicals, some of which don’t mix well, to work together to create a light beam.
Before blue lasers will be ready for commercial use, scientists need to show that the diodes can emit a continuous stream of blue light for 10,000 hours at room temperature. No one has done that yet.
Still, the harder task could be getting consumer electronics companies to agree on one standard, so blue laser discs can play in any machine.
The precedents are not encouraging. The most recent advance in digital storage, the digital video disc, or DVD, holds eight times more data than a conventional CD. It has yet to appear on store shelves, because the companies that developed it can’t agree on standards. Blue lasers also could fall prey to a format war.
“This industry is where the transistor business was in 1958--there were no standards until it became a commodity,” said Geoffrey Burnham, chairman of Semiconductor Laser International Corp., a Vestal, N.Y.-based start-up that makes high-powered red lasers.
The red semiconductor lasers that read today’s discs cost about $10. Blue lasers will have to cost about the same before companies are likely to build them into optical drives, said Dr. Diego Olego, head of blue laser research at Philips.
“There is no reason a blue-green laser can’t reach that price point,” Olego said.
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The rush to get blue lasers to market intensified earlier this year after Japan’s Nichia Chemical Industries unveiled a technical breakthrough that took the industry by storm. Sony owns a 5% stake in the closely held company.
Nichia, best known for fluorescent lights, reported in a scientific journal in January that it could make a blue laser by using a gallium nitride (GaN) chemical process.
“Nichia had a small group of people working in an isolated fashion, and they just surprised the world,” said Dr. Pam York, head of the microelectronic chemical systems group at the David Sarnoff Research Center in Princeton, N.J. “No one thought it could work. There were real technical obstacles.”
Most consumer electronics companies base their lasers on zinc selenide (ZnSe), which is easier to work with than gallium nitride. Sony, for example, is researching zinc selenide-based lasers at its own labs in Japan, in addition to its Nichia stake.
Philips, with funding from the U.S. Defense Department, has two projects underway at its labs in Briarcliff Manor, N.Y. One is with 3M, using zinc selenide, and the other with Cree Research Inc. of Durham, N.C., using gallium nitride.
Sony said in January that it had demonstrated a blue-green semiconductor laser based on zinc selenide chemicals that emitted a continuous wave for 100 hours at room temperature. Philips and 3M together did the same for 3 1/2 hours. Once a steady wave is produced at room temperature, increasing the duration can occur quickly, scientists said.
Toshiba said last month that it has used gallium nitride compounds to create a blue-purple semiconductor laser that emits a pulsed laser beam.
No one knows for certain how much consumer electronics companies have spent on blue laser research, but experts put the figure at about $100 million. One thing is for sure: The investment pales to the potential market.
The worldwide DVD market is expected to be $4.1 billion in 2000, according to market research firm Dataquest in San Jose.
Many people expect blue lasers to be right behind DVD.
“It’s human nature to want to save, record and retain information and memories,” said Phil Abram, director of Sharp Corp.’s multimedia development center in Mahwah, N.J. “This is a primal instinct. Why do you think people painted on cave walls?”
