How To Make A Black Light With Your Smartphone Led Flash

Did you know that you can make a black light (long wave ultraviolet light) using the light on your smart phone? Black lights come in all shapes and sizes, and are useful in a variety of ways— black lights can help you spot fake currency, urine stains, interesting rocks, and deadly scorpions. You can also use black lights to communicate in secret hidden messages using invisible inks that are only visible under long wave ultraviolet light. Black lights are an incredible addition to neon parties as they make white and fluorescent colors glow amazingly bright. 


This nifty tutorial will show you how to make a simple black light at home using only your smart phone, some tape and some sharpie markers. It won't work as well as a commercial LED black light, but if you're just looking to show off some cool fluorescent art or mutant-looking plants, it'll definitely do the trick. Click here to buy black light kits capable of lighting up an entire room for glow party raves. These are the best black lights for glow parties currently available anywhere in the world. They are designed to completely surround your party guests in ultra violet UV light. 

Most black lights work using a filter or coating over the bulb that filters out most of the visible light and produces mostly long wave ultraviolet (UVA) light in a dim violet glow (filter-less bulbs will produce a blue color). With a black light, you can see fluorescence, the radiating glow emitted by certain substances when exposed to ultraviolet light. While no current smartphone is technically capable of emitting UV light, you can mimic the effect of a black light using your phone's LED flash, a few markers, and some transparent tape. 


- A blue and purple marker
- Transparent tape
- Smartphone with LED flash 

To test your black light 
- Highlighter (yellow, orange or pink work best)
- White paper


This project can be literally be done is seconds if you have all of the materials in front of you. It's that easy. 
Place a small piece of tape over the LED flash on the back of your iPhone or Android smartphone (will also work on tablets with built-in flashes), which should be close to your rear camera. Paint on top of the tape with blue marker so that it covers the flash.
Place another piece of tape over top of the flash, and color on top of it with blue marker as well. Place a third and final piece of tape over the flash, but this time color over the flash with your purple marker.
You're done! Seriously, that's it.


On a piece of white paper, write/draw anything down with the highlighter, then turn on your device's flashlight feature in a dark room and shine the purple/blue tinted light at it. The writing on the paper should come to life thanks to your brand new DIY black light, giving it a prominent look in complete darkness. Depending on the type of highlighter you use, your results will vary (yellow, orange and pink highlighters tend to give the best results). Below are several examples, each from different highlighters, under my makeshift black light. 

If you want to take photos with the black light on, just make sure that you don't tape over the camera lens or you'll have a pretty blurry picture. Likewise for videos, though you'll also want to keep tape off of your microphone, too. Now that you have played around with a small DIY black light see the effects you can get from a commercial quality Glowave™ complete black light glow party kit