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25 March 2008


ITC investigating blue LED/laser patent infringement case

The US International Trade Commission (ITC) has agreed to institute an investigation based on a complaint filed on 20 February by Gertrude Neumark Rothschild, professor emeritus of Materials Science and Engineering at Columbia University.

The complaint (‘In the matter of Short-Wave Light Emitting Diodes’) alleges infringement by 34 firms of her 1993 US patent 5,252,499 ‘Wide band-gap semiconductors having low bipolar resistivity and method of formation’ (covering a method of producing gallium nitride-based semiconductors for LEDs and laser diodes emitting in the blue and ultraviolet). It also seeks to bar importation into the USA of a range of consumer electronics products incorporating infringing devices. These include DVD players using Sony’s Blu-ray format, Motorola Razr phones and Hitachi camcorders, as well as instrument panels, billboards, traffic lights and data storage devices. Other firms cited include Blu-ray DVD player manufacturers Matsushita Electric Industrial Co (Panasonic), LG Electronics Inc and Samsung Group and HD DVD player manufacturer Toshiba, as well as Nokia Corp, Sony Ericsson, Pioneer, Sanyo Electric, and Sharp Electronics.

In the complaint, lawyer Albert Jacobs of Dreier LLP claims that Rothschild made a ‘seminal breakthrough’ in the production of the blue and ultraviolet LEDs. “We’d like her to receive both the scientific recognition and the commercial recognition she so richly deserves,” said Jacobs.

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. She joined 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 and violet) 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. In 2008, she was selected as a recipient of Barnard College’s Distinguished Alumna Award.

After previous patent complaints filed elsewhere starting in 2002, LED makers including Toyoda Gossei, Osram Opto Semiconductors, and Nichia have already settled with Rothschild over alleged infringement of the patents. Most recently, on 11 March, Philips Lumileds settled in an action that had been brought before the US District Court for the Southern District of New York. A case against Cree Inc is still pending.

The latest case will be referred to ITC administrative law judge Paul Luckern, who will make an initial determination whether it will be subject to ITC review. Within 45 days after institution of the investigation, the ITC will set a target date for its completion. Any ITC remedial order in such a case is effective when issued and becomes final 60 days later, unless disapproved for policy reasons by the US Trade Representative.

See related item:

GaN-based laser diode market to more than double annually through to 2011

Search: GaN Blue LEDs Ultraviolet LEDs Blue laser diodes Blu-ray DVD