Phosphor banded stamp
Encyclopedia
Phosphor bands were introduced on British stamps from 1959 as a replacement for the previous graphite lined stamp
s as an aid in the mechanical sorting of mail.
The phosphor is applied in vertical bands, or more recently all over the stamp, and fluoresces
under ultra-violet light. This enables the mail sorting machine to face the mail and sort it into types.
Phosphor is now widely used on stamps around the world. It is necessary to use either a short or long wave ultra violet lamp to view the phosphor according to the type of phosphor used on the stamp.
Graphite lined stamp
A graphite lined stamp is a postage stamp on which vertical lines of electro-conductive graphite are printed on the reverse. Graphite lined stamps were used in the United Kingdom from 1957 to 1960 as an experiment in the automation of mail sorting....
s as an aid in the mechanical sorting of mail.
The phosphor is applied in vertical bands, or more recently all over the stamp, and fluoresces
Fluorescence
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation of a different wavelength. It is a form of luminescence. In most cases, emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation...
under ultra-violet light. This enables the mail sorting machine to face the mail and sort it into types.
Phosphor is now widely used on stamps around the world. It is necessary to use either a short or long wave ultra violet lamp to view the phosphor according to the type of phosphor used on the stamp.