How UV Barcodes Work

Learn about UV Barcodes and how they work.

There are two important things to know for UV ink:

1)      Excitation wavelength

This is the wavelength of light that the ink responds to. This is the wavelength of light that causes the ink to give off light. Typically, it is in the UV band, for example 390 nm.

2)      Emission Wavelength

This is the wavelength of light that the ink gives off when it receives light that excites it. This is typically a larger wavelength, for example 435 nm.

With regular ink, the ink absorbs light and the background (paper) reflects light. The reflected light is exactly the same as the light that we put on it. So, we give 660 nm light and the label gives the same 660 light.

But with UV ink, we give 390 nm light and the ink gives 435 nm back, not the 390. This is the special situation of UV ink.

Some UV ink works at different excitation wavelength and emission wavelength. So, we need to know these things about the UV ink for us to make a system that works. Our existing UV product works with 390 nm (the LEDs in the UV unit) excitation and 435 +-5 nm. We can make some different but we need to know the exact values for the ink and then we need to find LEDs if possible to make it work.

Learn more about Webscan’s TruCheck 2D USB UV barcode verifier.