Question

derive and discuss the condition of achromatism for two thin lenses by using two thin lenses of focal length f1 and f2, when they are made of different materials but placed in contact.​

Answer 1

Explanation:

ANSWER

Chromatic aberration occurs when a lens is either unable to bring all wavelengths of color to the same focal plane, and/or when wavelengths of color are focused at different positions in the focal plane.

A combination of converging and diverging lenses can form a non chromatic aberration image if

f1/f2= -w1/w2

w-----> Dispersive power