BOULDER, Colo., May 3, 2011 — A new series of graded-reflectivity mirrors from Research Electro-Optics Inc. (REO) enables precise spatial shaping of the intensity and phase characteristics of laser beams. In graded reflectivity mirrors, the reflectivity and/or phase effects of the coating vary radially across the surface of the optic. The company can produce these mirrors with virtually any arbitrary variation, including nonrotationally symmetric patterns, as well as with complex designs in which the reflectivity increases and decreases repeatedly across the component. The most common application for graded-reflectivity mirrors is as cavity optics in unstable resonator lasers. Here, the use of a second-order Gaussian or super-Gaussian reflectivity profile allows maximum power extraction from the resonator, as well as a smooth far-field output beam profile. A Gaussian profile mirror can also be used to achieve laser output with a uniform irradiance distribution, which is often required in illumination, materials processing and surgical applications. The ability to shape the phase of a laser’s emergent wavefront can aid in achieving better focusing characteristics and can improve coupling efficiency into optical fibers. The mirrors are offered on a wide range of substrate materials, including fused silica, various optical glasses, ZnSe, ZnS and Si, for operation over the 266-nm to 5-µm spectral range. They are available with diameters from 6 to 127 mm. Reflectivity pattern variations can be achieved down to a scale of approximately 1 mm. The use of ion beam sputtering coating technology makes the optics suitable for intracavity laser use and provides a combination of high damage threshold, spectral stability, environmental stability and mechanical durability that makes them compatible with other harsh and demanding environments.