MCQ
Which statement is correct for a zone plate and a lens
- ✓Zone plate has multi focii whereas lens has one
- BZone plate has one focus whereas lens has multiple focii
- CBoth are correct
- DZone plate has one focus whereas a lens has infinite
✓
Answer
Correct option: A.
Zone plate has multi focii whereas lens has one
a
(a) Multiple focii of zone plate given by ${f_p} = \frac{{r_n^2}}{{(2p - 1)\lambda }}$, where $p = 1,\,2,\,3\,......$
(a) Multiple focii of zone plate given by ${f_p} = \frac{{r_n^2}}{{(2p - 1)\lambda }}$, where $p = 1,\,2,\,3\,......$
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