(i) For a system of n-lenses in combination, the net focal length (f), net power (P) and magnification (m) are given as follows:
(ii) In case when two thin lens are in contact: Combination will behave as a lens, which have more power or lesser focal length.
(iii) If two lens of equal focal length but of opposite nature are in contact then combination will behave as a plane glass plate and f = infinity
(iv) If two lenses are placed co-axially at a distance d apart then equivalent focal length (F).
(v) Combination of parts of a lens:
Also see : (Click on these quick links)
Behaviour of lens under varying circumstances
1. Lens in different refractive index : http://www.askmattrab.com/notes/193-lens-in-surrounding-of-different-refractive-medium
2. Cutting of lens : http://www.askmattrab.com/notes/194-cutting-the-lens-in-different-shapes
3. Combination of lens : http://www.askmattrab.com/notes/195-combination-of-lens
4. Silvering of lens : http://www.askmattrab.com/notes/196-silvering-of-lens