Examples from the Web for achromatism
As the diameter of the lens was so small in comparison with its focal length, its want of achromatism was inappreciable.Experimental Determination of the Velocity of Light|Albert A. Michelson
Thus examined, the departure of the eye from achromatism appears very gross indeed.Six Lectures on Light|John Tyndall
The achromatism of prisms depends upon the same principles, and it is effected in the same way as that of lenses.
It would seem that the eye is but little sensitive to colours thus presented, perhaps on account of its own want of achromatism.
Leonhard Euler in 1747 had suggested that achromatism might be obtained by the combination of glass and water lenses.