An American university professor is claiming that Sony, Motorola and Nokia, among others, have infringed her patent.

Columbia University Professor Emeritus Gertrude Neumark Rothschild (that's a mouthful) filed a complaint last month against around 30 companies and has asked authorities to block imports into the US of a whole host of products, including Blu-ray disc players.

These are claimed to infringe Rothschild's patents relating to short-wavelength light-emitting diodes and laser diodes - the latter which are found in some PDAs and HD DVD players.

The complaint has now prompted an investigation by the US International Trade Commission.

Other companies embroiled in the row include Nokia, Motorola, LG and Panasonic maker Matsushita Electric - so, in other words, some of the biggest names in the consumer electronics arena.