University of Rochester

Hewlett-Packard Licenses University's 'Blue Noise Mask'

December 10, 1999

A halftoning technology developed by University of Rochester electrical engineers has been licensed to Hewlett-Packard Co., the world's largest maker of printers for computer use. The licensing comes as part of a settlement agreed upon last week by HP and Research Corporation Technologies (RCT) of Tucson, Ariz., which had filed a patent infringement lawsuit against HP. No other terms of the settlement were disclosed.

The technology is the subject of six U.S. patents and several international patents that have been issued; the patents were filed on behalf of the University by RCT, a company that helps universities commercialize technology developed in their laboratories.

The "Blue Noise Mask" invented by University researchers nearly a decade ago makes possible the rapid creation of high-quality halftones; at the time of the invention, the Blue Noise Mask derived halftones about 45 times faster than the leading technology. The inventors are Kevin Parker, dean of the School of Engineering and Applied Sciences, and former graduate student Theophano Mitsa, now a scientist at a Boston-based medical equipment company.

The pair began their project in an effort to improve the printouts of ultrasound images, where tiny visual mistakes or "artifacts" can be a serious hindrance to diagnosis and treatment. The research resulted in a new technology that eliminates artifacts not only in ultrasound images but in other images as well. In halftoning technology, "blue noise" refers to a certain type of pattern of black and white dots that has visually pleasing properties

"This research is a great example of the unforeseen benefits of basic research at a university," says Parker. "What started out as a medical imaging research project ended up as a technology that improves printing speed and quality in printers throughout the world."

More than a dozen companies have licensed the technology, which is widely used in the graphic arts and printing industry and in hundreds of thousands of printers and fax machines around the world. Other licensees include Raster Graphics Inc., Tektronix (now part of Xerox), (formerly known as Laser Master), and other companies.