Question

From the following, the wrong statement(s) about Huygens' eyepiece is(are) :

a) Cross wires can be arranged
b) It cannot be used in biological instruments
c) Condition for achromatism is satisfied
d) Condition for spherical aberration is satisfied

• A. a, b
• B. a, c
• C. b, d
• D. c, d

Answer 1

The correct option is A a, b

In Huygen's eye-piece cross wires cannot be arranged, it can be used in biological instruments. In it, condition of achromatism is satisfied because it uses plano-convex lenses. It also satisfies condition for spherical aberration.