ADE Phase Shift is a wholly owned subsidiary of ADE Corporation (Nasdaq: ADEX). As a company we design and build high precision systems for measuring the flatness, roughness and shape of advanced technology surfaces.

ADE Phase Shift was founded in Tucson as Phase Shift Technology, Inc. in 1987, by Chris Koliopoulos, Ph.D. and David Basila. The company soon offered a variety of interferometry-based products, including fringe analysis software, laser-based Fizeau interferometers, and microscope-based white light interferometers.
Interferometers use the natural wave properties of light, reflected from a surface to be tested, to map the tiniest surface height variations. Using interferometry, telescope mirror manufacturers gauge the quality and focus of their mirrors, and disk drive manufacturers make sure the platters used in computer disk drives are flat enough to withstand the high speeds and close quarters of the interior of a computer drive. It was Phase Shift interferometers that were used by the company that made the lenses that fixed the orbital Hubble telescope's blurred vision.

In 1998, Phase Shift Technology merged with Massachusetts-based ADE Corporation, a manufacturer of metrology equipment for the semiconductor and data storage industries. Since that time, the company has been called ADE Phase Shift.

ADE Phase Shift now makes products with applications for the measuring of the surface topology of polished silicon wafers, as well as systems for measuring critical surfaces in the hard disk industry, and many needs of optics manufacturers.