[shuttertalk]

If you've ever wanted to know what a pancake lens looks like on the inside (hint, the actual glass is really really small) - Petapixel tear apart the Olympus 17mm f2.8 m/43 mount and the Sony 18mm f2.8 E mount.

http://www.petapixel.com/2012/03/21/what...he-inside/

Lots of pictures inside - they actually show very detailed pics of every stage of the disassembly.

I was very surprised at how small the glass actually is, compared to say a standard zoom lens, and also how simple the construction is inside. I guess that's how they manage to make it so compact and flat.

[Toad]

So much mechanics and electronics - so little glass.

[NT73]

Despite the fact it has to cover a larger sensor, the elements in the Sony lens aren’t obviously larger than those in the Olympus.

As I understand all light waves converge in the centre cross over and then spread out the back, on to the sensor.
I imagine the size of the glass doesn't make much difference when related to a sensor.

A zoom lens is different to a fixed lens, regarding the distance between front and back elements to the sensor. I hope