The Collaborative International Dictionary
Wollaston's doublet
Wollaston's doublet \Wol"las*ton's dou"blet\ [After W. H. Wollaston, English physicist.] (Optics) A magnifying glass consisting of two plano-convex lenses. It is designed to correct spherical aberration and chromatic dispersion.
Note: Under "wollastonite" the eponymous inventor is described as a chemist.