https://www.lens66.com/products/achromatic-doublet-lenses/
Achromatic doublets are suitable for eliminating chromatic aberration and reducing spherical aberration on the image plane.
Elliot Jensen and Elliot Fintry have a lot in common. They share the same name, the same house, the same school, oh and they hate each other but, as they will quickly learn, there is a fine line between love and hate.