A federal judge has found that Microsoft Corp. encroached upon patents held by a Tucson, Arizona-based company for a process that improves the quality of images displayed on computer screens and paper printouts.

Senior U.S. District Court Judge William Browning on Tuesday granted a motion for summary judgment brought by RCT, ruling that the company has proved four patent claims while Microsoft failed to offer sufficient counterevidence. The software maker now has to defend itself in front of a jury, according to a copy of the judge's order.

"The judge has determined that Microsoft is guilty of patent infringement and that the technology is used in some of Microsoft's biggest products," Ferguson said.

The case will now continue to trial, where a jury will hear evidence and determine the extent of the patent infringements and the resulting damages to RCT. The potential damages could be worth hundreds of millions of dollars, Ferguson said.