Toronto. Mid last century science perfected a lens coating that improved the contrast of lens designs allowing even more elements to further correct lenses, paving the way for the complex zoom lenses commonplace today.
And now modern coating technology has evolved to allow chromatic aberrations to be corrected so that all colours focus at the same plane without resorting to additional elements.
My thanks to Russ Forfar who enjoys Science Daily and its research news. On November 20, 2018 in an article written by Harvard’s John A. Paulson School of Engineering and Applied Science (SEAS) researchers report how a single layer of nano structures can be used to correct chromatic aberrations. This has implications in the design of miniature lens systems for smartphones as well as designs for complex microscope objectives.