Inclination-independent transformation of light beams using high-throughput uniquely-curved micromirrors

We report a novel class of specifically-designed curved micromirrors enabling phase transformation of light beams independent of their inclination angle. The surface also exhibits a linear relationship between inclination angle and transversal displacement of the beam. The micromirrors were alkaline-free etched to depth levels of more than 300 μm, thus enabling high optical throughput. Measurements at both 675 and 1550 nm wavelengths show stable dimensions for the optical beam spot with less than ± 5% dependence on the inclination angle up to 60 degrees. The presented micromirros have applications in optical beam shaping and scanning, displacement/rotation sensing and imaging.