We’ve already written an article showing you how to detect pet urine using a simple UV flashlight. The principle is exactly the same to detect sperm stains. You just need to use a cheap UV flashlight in a dark environment, like this pocket-size device which you can find on Amazon.
This compact UV flashlight as more than 10,000 reviews on Amazon, which shows how popular fluid detection is.
How to detect sperm stains in underwear?
If you think your partner might have had a secret relationship, you can use this black light technique to detect potential sperm stains in her underwear.
Your UV flashlight will also detect body fluids on any other clothes, even on bed sheets. The same basic technique is used by police forces in crime investigations.
How to detect sperm with your phone?
You can create your own UV flashlight with a smartphone. Simply cover the flash of your phone with sticky tape. Then colour over the tape with a blue pen. Add a second layer of tape to protect the colouring.
This will transform your phone into a portable investigation tool. You’ll be able to easily track body fluids on any surface.
Do vaginal fluids glow in the dark?
Sperm isn’t the only fluorescent body fluid. Saliva, blood and vaginal fluids also have the same property when exposed to black light. So you can use your UV flashlight (or your DIY version) to detect vaginal fluids on bed sheets or in clothes.
According to forensic experts sperm tends to glow more than vaginal fluids simply because semen is generally thicker and doesn’t spread as much on the sheets. The density of phosphors reflecting UV light tends to be higher in semen which lights up brighter.