Ultraviolet (UV) radiation is widely used in the detection of counterfeit items due to its ability to reveal features that are invisible under normal light. Here’s how it works:
- Invisible Inks and Dyes: Many authentic documents, currency notes, passports, and branded products are marked with special UV-reactive inks or dyes. These markings glow or change color under UV light but remain invisible under regular lighting. Counterfeit items often lack these secure features or use poor imitations.
- Currency Verification: Genuine banknotes often have embedded security threads, watermarks, or serial numbers that fluoresce under UV light. These features help cashiers and machines verify authenticity.
- Document Authentication: Passports, ID cards, certificates, and tickets may include UV-sensitive holograms or microtext that only appear under UV illumination. Government and institutional documents often rely on such hidden elements for anti-forgery protection.
- Brand Protection: Manufacturers of luxury goods, pharmaceuticals, or electronics may apply UV-visible tags or labels. These may include logos or product codes that help identify originals and trace their supply chains.
- Forensic and Quality Control Use: UV light helps investigators check for tampered packaging, erased marks, or added features not present in originals.