Fluorescent Multilayer Card

Using the same technology as the fluorescent multilayer disc, the fluorescent multilayer card is a card containing a square shaped clear part which has multiple layers each with a different fluorescent material that reflects light at a different frequency than the other layers, so that the number of layers is limited only by the thickness of the card. Because of this, a card with the data area roughly 25millimetre or one inch wide should be able to hold 10gigabyte of data.