SBIR Phase I:Three-Dimensional Microscopy of Surfaces by Grazing Incidence Diffraction

This Small Business Innovation Research Phase I project will demonstrate and report upon a new holographic method for three-dimensional (3D) metrology whereby micron scale surface profiles are taken over wide lateral dimensions with significant non-contact stand-offs. The method uses a prefabricated surface relief holographic grating as its first element, the "primary objective," and a sheet of laser light for illumination. The images formed in the secondary are 3D profiles. The microscope exhibits anamorphic magnification in the depth dimension permitting a wide field-of-view in the lateral dimension. It also enjoys a significant stand-off to target, which is particularly useful in non-contact instruments. In addition, this diffraction microscope maintains focus over its entire working depth. There is steady demand for improvements in advanced 3D microscopy to enable new applications. The relevant markets are characterized by effective competition, within the limits set by patent protection. Sales of microscopes in year 2000 were reported as $800 million in a marketplace that is dominated by visible light types at $520 million. A 3D microscope is the confocal type which was reported to have a 6% share of the market in 2000. By 2001 its market share was reported to be 7.5%.