\r\nUV-A<\/strong><\/td>\r\n315-400 nm<\/td>\r\n Currency verification, forensic analysis, and tanning lamps<\/td>\r\n<\/tr>\r\n \r\nUV-B<\/strong><\/td>\r\n280-315 nm<\/td>\r\n Skin treatment and sterilization<\/td>\r\n<\/tr>\r\n \r\nUV-C<\/strong><\/td>\r\n100-280 nm<\/td>\r\n Germicidal purposes, air, and water purification<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/figure>For currency verification, UV-A light (between 365-395 nm) is commonly used because it reveals fluorescent security features without damaging the banknotes.<\/p>
<\/span>2. Security Features on Banknotes Revealed by UV Light<\/strong><\/span><\/h3>Modern banknotes are designed with advanced security features that fluoresce or absorb UV light. Below are some examples:<\/p>
<\/figure><\/div>\r\n\r\n\r\n\r\nFeature<\/strong><\/th>\r\nDescription<\/strong><\/th>\r\nReaction to UV Light<\/strong><\/th>\r\n<\/tr>\r\n<\/thead>\r\n\r\n\r\nFluorescent Fibers<\/strong><\/td>\r\nTiny fibers embedded into the paper during manufacturing.<\/td>\r\n Glow in specific colors like red, green, or blue.<\/td>\r\n<\/tr>\r\n \r\nSecurity Threads<\/strong><\/td>\r\nThin strips embedded or printed within the note.<\/td>\r\n Appear as a continuous line glowing under UV light.<\/td>\r\n<\/tr>\r\n \r\nInvisible Ink<\/strong><\/td>\r\nPatterns or symbols printed with UV-reactive ink.<\/td>\r\n Visible only under UV light, glowing in distinctive colors.<\/td>\r\n<\/tr>\r\n \r\nWatermarks<\/strong><\/td>\r\nPatterns visible when held to light but unaffected by UV light.<\/td>\r\n Do not fluoresce, aiding in distinguishing fake watermarks.<\/td>\r\n<\/tr>\r\n \r\nSerial Numbers<\/strong><\/td>\r\nSerial numbers or portions of them printed with UV-sensitive ink.<\/td>\r\n Certain digits fluoresce under UV light.<\/td>\r\n<\/tr>\r\n \r\nNon-Fluorescent Areas<\/strong><\/td>\r\nSpecial regions designed to absorb UV light, such as dark logos or emblems.<\/td>\r\n Remain dark and non-reflective, contrasting with fluorescent areas.<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/figure><\/span>3. Technology Behind UV Light in Currency Verification<\/strong><\/span><\/h3>UV light’s interaction with security features is based on fluorescence and absorption:<\/p>
Fluorescence<\/strong>: Certain inks and materials emit visible light when exposed to UV radiation. This fluorescence is specific to the material, making it hard to replicate.<\/li>\r\n\r\nAbsorption<\/strong>: Genuine banknotes have regions that absorb UV light and remain dark, a detail often overlooked in counterfeit production.<\/li><\/ul><\/span>4. Practical Application in Currency Verification<\/strong><\/span><\/h3><\/span>Step-by-Step Guide:<\/strong><\/span><\/h4>Prepare the Environment<\/strong>Use a low-light environment to enhance the visibility of UV-reactive features.<\/li><\/ul><\/li>\r\n\r\n Inspect the Note<\/strong>Shine the UV flashlight evenly across the note. Look for glowing fibers, threads, and patterns.<\/li><\/ul><\/li>\r\n\r\n Cross-Check Features<\/strong>Compare the security features with the official guidelines for that currency.<\/li><\/ul><\/li>\r\n\r\n Look for Contrasts<\/strong>Ensure non-fluorescent areas remain dark and absorb UV light properly.<\/li><\/ul><\/li><\/ol><\/span>5. Comparison of Genuine vs. Counterfeit Notes Under UV Light<\/strong><\/span><\/h3> <\/figure><\/div>\r\n\r\n\r\n\r\nFeature<\/strong><\/th>\r\nGenuine Note<\/strong><\/th>\r\nCounterfeit Note<\/strong><\/th>\r\n<\/tr>\r\n<\/thead>\r\n\r\n\r\nFluorescent Features<\/strong><\/td>\r\nBright and uniform glow.<\/td>\r\n Uneven or absent glow.<\/td>\r\n<\/tr>\r\n \r\nSecurity Threads<\/strong><\/td>\r\nEmbedded and consistent under UV light.<\/td>\r\n Often missing or poorly replicated.<\/td>\r\n<\/tr>\r\n \r\nInvisible Ink Patterns<\/strong><\/td>\r\nMatch official currency designs.<\/td>\r\n Mismatched or irregular patterns.<\/td>\r\n<\/tr>\r\n \r\nDark Areas<\/strong><\/td>\r\nNon-fluorescent, consistent with original design.<\/td>\r\n May exhibit unintended fluorescence.<\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/figure>