How are 3D motion stickers made?

Question:

How are 3D motion stickers made?

My daughter likes the stickers and cards that change images - flower to butterfly, prince to Shrek, etc. They have lightly parallel-grooved surfaces.

Best Answer - Chosen by Asker: The grooved surface allows views of several different images which are laid down in thin stripes behind them. The images may be very different (pretty girl, bottle of beer), somewhat different (an eye that winks at you) or various views of the same object from different angles (like a rotating sculpture). The technology involved in making them is similar to making a hologram so it is possible to combine the two so a 3D transmission hologram is laid down in thin stripes so that each eye sees a slightly different view, making it appear 3D or 3D and moving.