Want to know what's next in the world of airplane interiors? If so, the annual Aircraft Interiors Expo in Hamburg, Germany, is the place to be. The 2014 edition was held last week, showcasing a wide range of designs for airplane interiors.

Whether an attempt to ease the crush of squeezing ever more seats into the economy class cabins or to make business class a bit more economical for the airlines, seat manufacturers are constantly tweaking "normal" layouts and amenities in an effort to optimize the cabin.

In the middle are a growing number of premium-economy offerings in which airlines roll out a separate seat and class of service that's somewhere between business class and regular economy. Those sections haven't caught on in the U.S., though they've been growing in popularity at airlines in the rest of the world.

While the new designs covered all types of fliers, not all of the ideas presented at the 2014 Expo will fly. But there is plenty of creativity to be seen in the work airline seat designers who showed off their work in Hamburg.

We take you along for a behind-the-scenes tour as we look at some of the Expo's more interesting designs, including some that you might actually see flying for U.S. airlines.