Data recorded credit card - has data stored in fluorescent compound read by IR source

摘要

A data card of the type used as credit cards contains information stored that is read by an IR beam. The aim is to record the data such that it may be accurately read even though folds and marks are present. The card (1) has information recorded using a compound of neodymium (2) that exhibits a sharp absorption and emission characteristic at specific wave lengths. An infrared beam (6) is directed onto a slit (4) onto the card and the reflected light is detected (9) after transmission through a fibre optic bundle (8) over a filter. Other flourescent compounds, such as ylterbium and erbium may be used.