A combination of two thin lenses of the same material with focal lengths f1 and f2, arranged on a common axis minimizes chromatic aberration, if the distance between them is:

Question

A combination of two thin lenses of the same material with focal lengths f1 and f2, arranged on a common axis minimizes chromatic aberration, if the distance between them is: (A)  (( f1+f2 )/4)  (B)  (( f1+f2 )/2)  (C)  ( f1+f2 )  (D)  2( f1+f2 )

Tardigrade Admin · Accepted Answer

Condition for achromatism for two thin convex lenses of same material and mean focal lengths f1 and f2 placed at a distance d apart form an achromatic combination provided, d=(f1+f2/2) This combination is free from lateral chromatic aberration for all colours.

Q. A combination of two thin lenses of the same material with focal lengths f1 and f2, arranged on a common axis minimizes chromatic aberration, if the distance between them is:

$\frac{( f _{1} + f _{2} )}{4}$

$\frac{( f _{1} + f _{2} )}{2}$

$(f_{1} + f_{2})$

$2 (f_{1} + f_{2})$

Condition for achromatism for two thin convex lenses of same material and mean focal lengths $f_{1}$ and $f_{2}$ placed at a distance d apart form an achromatic combination provided, $d = \frac{f _{1} + f _{2}}{2}$ This combination is free from lateral chromatic aberration for all colours.

Q. A combination of two thin lenses of the same material with focal lengths f1 and f2, arranged on a common axis minimizes chromatic aberration, if the distance between them is:

4(f1​+f2​)​

2(f1​+f2​)​

(f1​+f2​)

2(f1​+f2​)

Condition for achromatism for two thin convex lenses of same material and mean focal lengths f1​ and f2​ placed at a distance d apart form an achromatic combination provided, d=2f1​+f2​​ This combination is free from lateral chromatic aberration for all colours.

$\frac{( f _{1} + f _{2} )}{4}$

$\frac{( f _{1} + f _{2} )}{2}$

$(f_{1} + f_{2})$

$2 (f_{1} + f_{2})$

Condition for achromatism for two thin convex lenses of same material and mean focal lengths $f_{1}$ and $f_{2}$ placed at a distance d apart form an achromatic combination provided, $d = \frac{f _{1} + f _{2}}{2}$ This combination is free from lateral chromatic aberration for all colours.