Feb. 20 (Bloomberg) -- Sony Corp., Motorola Inc. and Hitachi Ltd. were among 34 companies accused of violating a retired Columbia University professor's patent for light-emitting diodes and laser diodes.

Gertrude Neumark Rothschild filed the complaint today with the U.S. International Trade Commission in Washington. She is seeking to block U.S. imports of products that she says infringe the patent, including video players using Sony's Blu-ray format, Motorola's Razr mobile phones and Hitachi camcorders.

Rothschild made a ``seminal breakthrough'' in the production of blue, ultraviolet and white light, said her lawyer, Albert Jacobs of Dreier LLP in New York. Blue and ultraviolet LEDs, which use less electricity than red LEDs, are used in computers, traffic lights, instrument panels and as the background color for mobile-phone screens.

``We'd like her to receive both the scientific recognition and the commercial recognition she so richly deserves,'' Jacobs said in a telephone interview. Rothschild did her research while an engineering professor at Columbia in the 1980s and 1990s, according to the complaint.

Companies named in the complaint include Matsushita Electric Industrial Co., LG Electronics Inc. and Samsung Group, makers of Blu-ray DVD players, as well as Toshiba Corp., which said yesterday it would abandon the HD DVD format that challenged Sony in the market for high-definition video.

Nokia Oyj, the world's biggest mobile-phone maker, and Sony Ericsson Mobile Communications AB, the joint venture between Tokyo-based Sony and Ericsson AB of Sweden, also were named in the complaint.

Lauren Carhart, a spokeswoman for Samsung, declined to comment. Officials at the other companies either had no comment or didn't immediately respond to messages.

The ITC is a government agency that aims to protect the U.S. market from unfair trade practices, including patent infringement. It typically agrees to investigate complaints and makes decisions in about 15 months.

The case is In the matter of Short-Wave Light Emitting Diodes, Complaint No. 2601, U.S. International Trade Commission.

To contact the reporter on this story: Susan Decker in Washington at sdecker1@bloomberg.net.

Last Updated: February 20, 2008 16:29 EST