Question

A combination of two thin convex lenses of focal length $0.25\text{m}$ and $0.12\text{m}$ will have minimum spherical and chromatic aberrations if the distance between them is

• A. $0.31\text{m}$
• B. $0.37\text{m}$
• C. $0.13\text{m}$
• D. $1.3\text{m}$

Answer 1

The correct option is C $0.13\text{m}$

The required separation between the lenses to have a minimum aberration is given by .
$D=f_1-f_2=0.25-0.12=0.13\text{m}$
So, if both the lenses are separated by the distance of $0.13\text{m}$ , then there will be less chromatic aberration.