Challenges of Coating Aspheric Lenses

Aspheric lenses let optical system designers improve resolution, reduce the number of lens elements required, and increase system light throughput. Their complex, non-spherical surfaces correct for more spherical and higher-order aberrations than the spherical surfaces of conventional lenses. However, aspheres often have steeper surface angles than spherical lenses, which introduces unique challenges while depositing optical coatings.