LG Display, Sharp and Chunghwa Picture Tubes of Taiwan have pleaded guilty to fixing the price of LCD display panels in a recent case brought by the US Justice Department.

The three companies have agreed to pay a total of $585 million in criminal fines with LG paying out the most with a $400 million fine, the second-highest criminal fine ever imposed by the Justice Department's antitrust division.

The price-fixing conspiracy was said to be an effort to slow the speed of price declines.

The American investigation - that involved enforcement officials in Europe and Asia - said that Dell, Apple and Motorola were affected, and may chose to take up private suits.

With government investigations under way in Europe, Japan and South Korea, the three companies are also facing private class-action suits from consumers who bought flat-panel-equipped products with inflated prices.