Can a normal black light be used to test for UV reflection?
A normal blacklight does emit UV but our eyes can’t see it. Black lights also emit a small amount of visible light near the lower end of our wavelength range. This is the violet light we see when a black light is on. Youd need UV imaging equipment to see the UV light coming off a black light. When our T-shirts glow under a black light, we are not seeing UV reflection. Objects that glow under a black light are fluorescent – they absorb the UV and re-emit it as visible light. That’s why a white t-shirt seems so bright under a black light, it takes the invisible UV and converts it to visible. Blaze orange and other fluorescent colors do the same thing, just at different wavelengths. Some people mistakenly call fluorescent paint UV paint but it isn’t. If an object glows brightly under a black light, it is absorbing UV.
