Which statement is correct for a zone plate and a lens. | PHYSICS - POLARISATION | SolveeIt | Solveeit

Today, August 19

Question

Which statement is correct for a zone plate and a lens.

A

Zone plate has multi focii whereas lens has one

B

Zone plate has one focus whereas lens has multiple foci

C

Both are correct

D

Zone plate has one focus whereas a lens has infinite

Answer

Zone plate has multi focii whereas lens has one

Explanation

Solution

Multiple focii of zone plate given by $f_{p} = \frac{r_{n}^{2}}{(2p - 1)\lambda}$ , where $p = 1,2,3......$