Laser etched Transparency

While I was at the local bookstore looking for a sheet of transparency to transfer the Tricorder sticker to, I found this special sheet. It costs me RM0.80 and there were several patterns to choose from. Since I was in a hurry, I just chose this piece. But one day, I would definitel need to go back there to see if they have anymore designs.

Now the Big Question is, what am I going to do with it?

To the normal eye, when you hold it like this, its just
a normal piece of acetate/transparency. But already,
you would have noticed something different about it

Yes, there are rainbow colours and they're all arranged in
small little squares. So, I need to tilt it against the light and
now, you can see the interference which created the colours

OK, a flash to show you more. Nice or not?