In this article, I'll show you how to make an awesome "Death Ray" using the large magnifying lens from an old projection TV. The lens is called a Fresnel lens; a device that employs several ridges to focus light, rather than a complete curve.
When sunlight passes through the Fresnel lens, it changes direction towards one specific point. When several beams of high-powered sunlight meet at that point, it intensifies the power of the sun and incinerates anything in its way. You can read more about Fresnel lenses here.
To build this giant death ray, you'll need:
- Old projection television (the bigger the better)
- Screwdrivers (depending on your TV)
- Some 2x4s (optional; only necessary if you want to build a frame)
- A workspace
In order to use the Fresnel lens, it's necessary to open up the TV and remove the frame. Here's a video demonstration of the deconstruction:
Once you've removed the lens, you can either use it as-is (just find some sun, and focus it!), or make a frame to hold it in. Here are a couple variations:
Here's an instructional video of how to make a stand:
I'd recommend making a stand, it protects the lens and also is very convenient. However, it is quite bulky and hard to store. Here's a video of the lens in action!
- THE SUN IS VERY DANGEROUS. ALWAYS wear eye protection, and DO NOT ever allow the beam to come in contact with skin, it will INSTANTLY burn you.
- DO NOT aim the magnifying lens at anything living!
- The lens is fragile, be careful.
- Power tools are dangerous! Be careful.
- I am not responsible for any damage or harm you cause.