New method eliminates distortions in micromirror optical devices

A team of researchers has developed a new method to correct distortions in micromirror devices. These devices, known as spatial light modulators, are essential for creating dynamic optical patterns. The breakthrough addresses long-standing challenges in shaping light beams with precision. Munkyu Kang, Elizabeth Murray, Leyla A. Kabuli, and their colleagues identified that stress during fabrication often causes micromirrors to curve. This curvature degrades the performance of the devices, making it difficult to achieve accurate light control.

The team introduced a carefully designed microlens array to refocus light onto the centre of each micromirror. This eliminates the distortions caused by fabrication flaws. As a result, the brightness of the generated light patterns increased eightfold, and the correlation of the phase profile improved from 0.11 to 0.85.

Their approach also achieves nearly 100% fill factor. This means the method enhances both the efficiency and accuracy of the light patterns produced. The new technique enables scalable, high-fidelity wavefront control. It opens doors for advancements in fields like holographic displays and optogenetics, where high-speed light manipulation is critical. The method offers a practical solution to a persistent problem in optical technology.