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27 May 2008


Consumer electronics firms license Rothschild LED patents

Four consumer electronics companies, Sony Corp and Sanyo Electric Co Ltd, Exceed Perseverance Electronic Ind Co Ltd, and Lucky Light Electronics Co Ltd, have agreed to license patents owned by Gertrude Neumark Rothschild, professor emerita of Materials Science and Engineering at Columbia University.

The agreements follows an investigation instituted on 20 March by the US International Trade Commission (ITC) based on a complaint (‘In the matter of Short-Wave Light Emitting Diodes’) filed by Rothschild alleging infringement by 31 firms of patent 5,252,499 (covering a method of producing gallium nitride-based semiconductors for LEDs and laser diodes emitting in the blue, green, violet and ultraviolet end of the spectrum).

The complaint seeks to bar importation into the USA of a wide range of consumer electronics products incorporating infringing devices. These include video players using Sony’s Blu-ray format, Motorola Razr mobile phones and Hitachi digital camcorders, as well as instrument panels, billboards, traffic lights and data storage devices. Other firms cited include Blu-ray DVD player makers Matsushita Electric Industrial Co (Panasonic), LG Electronics Inc and Samsung Group and HD DVD player manufacturer Toshiba Corp, as well as Nokia Corp, Sony Ericsson Mobile, Pioneer, Sanyo Electric Co, and Sharp Electronics.

License agreements were signed with Rothschild by LED makers Seoul Semiconductor Co Ltd of South Korea and Everlight Electronics Co Ltd of Taipei, Taiwan in April and Epistar Corp of Hsinchu, Taiwan in early May.

Of the 31 companies named in the action, Sony, Sanyo, Exceed and Lucky Light join Everlight in agreeing to license the patents. Other companies named include Hitachi Ltd., Matsushita Electric Industrial Co, LG Electronics Inc, Nokia Corp, Samsung Group, Sharp Corp. Sony Ericsson Mobile and Toshiba Corp.

“These latest licensing agreements are important milestones in this case,” says Albert L. Jacobs Jr, an intellectual property partner with Rothschild’s legal representatives Dreier LLP. “Rothschild made a seminal breakthrough in understanding the doping requirements necessary for the production of the blue, green, violet and ultraviolet LEDs and LDs on a commercial and efficient scale that are essential to today’s consumer electronics,” he adds.

Rothschild began her research career in private industry, working with Sylvania Research Laboratories in Bayside, NY in the 1950s and later at Philips Laboratories in Briarcliff Manor, NY before joining Columbia as a professor of materials science in 1985. She conducted research in the 1980s and ’90s into the electrical and optical properties of wide-bandgap semiconductors that is claimed to have been pivotal in the development of short-wavelength emitting (blue, green, violet and ultraviolet) diodes now used in consumer electronics.

Recognized by the American Physical Society as a Notable Woman Physicist in 1998, Rothschild was elected as a Fellow of the American Physical Society in 1982. Earlier this year, Rothschild was honored by Philips Electronics, which endowed the new Philips Electronics Chair in the Department of Applied Physics at the Fu Foundation School of Engineering and Applied Science at Columbia University.

On 10 March, an action that had been brought before the US District Court for the Southern District of New York by Rothschild was settled by LED maker Philips Lumileds of San Jose, CA, USA, giving the firm a non-exclusive license. Previously, after patent complaints filed elsewhere starting in 2002, LED makers including Germany’s Osram Opto Semiconductors and Japan’s Nichia and Toyoda Gosei also settled with Rothschild over alleged patent infringement. A separate case against LED maker Cree Inc of Durham, NC, USA is still pending.

See related items:

Epistar licenses Rothschild LED patents

Seoul and Everlight settle ITC action brought by Rothschild

Seoul Semiconductor agrees license with Rothschild

ITC investigating blue LED/laser patent infringement case

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