High light-directing micrometer-sized parabolic mirror arrays

Excellent light-directing abilities are demonstrated by well-designed three-dimensional micrometer-sized parabolic mirrors that are fabricated by direct laser writing and subsequent surface coating of titanium and silver. The full-width at half-maximum of the measured light divergence for the mirrors with different geometries is much less than 20 μm, even when the height is up to 130 μm. These results are beneficial for developing highly collimating light-emitting diodes. The simulation for the mirrors reveals that the electric field intensity distribution is highly confined toward the central axis of the mirrors, which is consistent with the experimental results.