Some time ago we had a thread on the diffraction pattern used as a security feature in a Canadian dollar.
Here is an image I took when shining a red laser through the note.
There was a great video shared on here.
I tried a laser through the new 5 pound note
You can see the queen is made of little plastic dots on clear plastic The region that I got the best diffraction from was under the Queen’s chin and you can see the ordered spacing that created it here
Hi Alessio, I shone the laser through clear maple leaf is. The blue dot in the dollar below.
The dollar I had is in the IOP Electromagnetic Workshop box and was a shown at the East Midlands day. I seem to remember that I could see no dollar pattern and was convinced that it is a true diffraction pattern. When I get hold of one again I will use my dino-light microscope to have a look. In the pictures above I used the dino-light to magnify the £5 pound note enough to see the little blobs of plastic.