Q. 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 focii
C) Both are correct
D) Zone plate has one focus whereas a lens has infinite
Explanation
(a) Multiple focii of zone plate given by $f_{p} = \frac{r_{n}^{2}}{(2p - 1)\lambda}$
Where $p = 1,\ 2,\ 3\ldots$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.