Cheap UV Bank Note Checker

2013-07-11 08:21 By Jason Birch

UK £20 Bank notes use several security features to help prevent fake bank notes. One of which is an area of the bank note which is visible only under a UV light source.

VIDEO The video here demonstrates the project which this article describes how to build. The article breaks the project down into several stages: Background Components Operation Project Costing

Background To prevent fakes there are several security features on UK bank notes. A water mark of the queen in the paper on the left side, where the queen faces the queen printed on the note. A metal foil strip which runs down the note, inside the paper. Hologram images on a strip running down the note. Raised lettering "Bank of England" at the top of the note. Bank note under normal light Components Only a few components are required, a UV LED, coin cell battery holder, switch and small piece of strip board. Because of this the circuit is very simple.

And on a £20, a red "20" with diamond symbols at the top center, only visible under UV light. A cheap UV light source can be made for a few pounds which will allow the UV security portion of the bank note to be viewed. This is one of the most secure features of the £20 bank note. In addition the note contains small white hairs which can be seen under UV light. Bank note under UV light Operation A commercial UV light will provide much more light at a higher intensity, but for a much higher cost. When using this project, to reduce the amount of natural light illuminating the area, cup your hands around the note and device while pressing the button. This provides enough light to see the security print. I have found on newer notes the UV area illuminates much better than on old notes.

Project Cost
Item	Reference	Qty	Each	Cost
Ultra-Violet 5mm LED	BitsBox	1	£1.00	£1.00
Coin cell battery holder	BitsBox	1	£0.59	£0.59
Tactile switch 6x6mm - Round Button	BitsBox	1	£0.20	£0.20
Strip Board 25 x 64mm	BitsBox	1	£0.31	£0.31
CR232 Battery	PoundLand	1	£1.00	£1.00
TOTAL				£3.10