What is fluid focus lens?

It is a lens made up of two miscible fluid of different refractive index:

one a electrically conducting aqueous solution and the other an electrically non-conducting oil. It has no moving parts . Now it is used in phone ,cameras etc.

This works on the principle of mimics the action of the human eye using a fluid lens that alters its focal length by changing its shape.This also overcomes the fixed-focus disadvantages of present lenses