Question

when we two structures of different numerical aperture joined longitudinally, then what's the final numerical aperture.assume x of first structure S1, and y of second structure S2 (y<x )

Answer 1

Refer to the attachment for diagram

The numerical aperture is been limited by the second glass slab ( y )

Since Sin i₂ is lesser than y. This implies that Sin i₁ is greater than Sin i₂.

Hence Final numerical aperture = Smaller aperture = y