Japan Sankyo SANKYO F20T10BLB blue black violet lights, fluorescent black light tube arc energy can be converted to violet lamp UV-A band of long-wave ultraviolet radiation, UVA radiation wavelength 340nm to 380nm, the center value is 365nm, the lamp by black and blue glass, can be visible through the little, but does not affect glow. Uses: Industrial glue curing, tungsten ore identification, fluorescence detection, biopolymer, oil testing, mineral exploration, criminal detective, textile industry, archeology, medical, stage, nightclubs, theaters and signal lighting. 1. Many ore will fluoresce under ultraviolet light, the fluorescence emitted at different ultraviolet radiation of different wavelengths simultaneously in the same ultraviolet irradiation, chemical composition of the ore is different from the color of emitted fluorescence will be different, and therefore, ultraviolet light has been detected ore an important tool. 2. excited by ultraviolet light oil substances characteristic fluorescent detection of grease / dirt on the workpiece. 3. clones use them to detect the authenticity of antiques. There are many pigments containing phosphorus, it will glow in ultraviolet light, and most of the old paint is not contain phosphorus. 4. Maintenance personnel use them to identify the machine --- invisible cracks by injecting a small amount of fluorescent dye into the fuel supply and illuminated it with ultraviolet light. 5. The law enforcement officials could use them to identify the authenticity of the money. United States and many other countries in their large denomination with a invisible fluorescent strip, they only show up only under ultraviolet light. 6. Forensic scientists use them to analyze the scene. For fingerprints, for example, they are usually sprinkled with fluorescent dye under ultraviolet light. So that you can more easily fingerprints.