Three electronics firms have agreed to plead guilty and pay $585 million in fines for conspiring to drive up prices for people buying computers, TVs and other LCD screens.

In a plea deal filed Wednesday, LG Display Co. Ltd., Sharp Corp., and Chunghwa Picture Tubes Ltd., agreed to cooperate in an antitrust investigation being run by the Justice Department.

The plea agreement was filed in federal court in San Francisco.

LCDs, or liquid crystal display monitors, are the glass display screens on most laptop computers, cell phones and new TVs.

Deputy Assistant Attorney General Scott D. Hammond said the scheme cost not only consumers, but also retailers including Apple, Dell and Motorola.

Hammond did not have a cost value for the losses, and said the investigation is continuing.

"These price-fixing conspiracies affected millions of American consumers who use computers, cell phones and numerous other household electronics every day," Hammond told reporters at a Justice Department briefing announcing the deal. "By conspiring to drive up the price of LCD panels, consumers were forced to pay more for these products. And consumers were not the only ones affected by these conspiracies."