Lenses made of water and oil?

It sounds bizarre, but liquid lenses could be the future of cameraphones. They have been proposed for ages, by Philips among others, but French company Varioptic and Chinese optical company Sunny have produced a module that they hope will appear in cameraphones soon.
Liquid lenses work by holding a drop of oil inside a metal ring, held in place by water. When a voltage is applied to the ring, the water is drawn along it to compress the oil into a spherical droplet - that is, a lens.
Varying the voltage instantly changes the shape of the oil droplet, changing the focal length. Both autofocus and zoom lenses are possible.
The advantages of using liquid are very small size and high speed compared with mechanical arrays. They are also cheap.
The Varioptic module is only 2MP, so it will not be competing with the top glass lens systems. Recent experience has shown that cameraphones can only compete with regular cameras by using top quality lenses, glass rather than plastic, so it will be interesting to see if liquid lenses rule the world or become a cheapo alternative for happy-snappy phones.