In Fall 2020, I got an old broken CRT monitor from my college's recycling cage and turned it into a helmet with a working RGB LED display. Here's some information about how I made it and how it works. If you want to make a TV head without the electronics, this method should still work if you ignore all the electronic parts. If you just want to see the finished costume, skip to the gallery.
Non-electronics
I disassembled the CRT monitor, being careful to discharge the cathode to avoid a painful electric shock. (I think my monitor was self-discharging anyway, but it's a good idea to be sure.) I put the big glass cathode ray tube away in a cardboard box so I wouldn't accidentally trip over it and make it implode, which would be unpleasant for multiple reasons. I cleaned out the inside of the monitor and shook out the dead ladybugs that had collected inside over the years. I eventually used a dremel to cut a hole in the bottom of the monitor just big enough to fit my head through.
My first prototype used plexiglass for the screen, but I found that a thinner sheet of polycarbonate was much lighter on my neck and flexible enough to bend into a convex shape, which makes the helmet look more realistic. I tinted the polycarbonate using some privacy window film.
The most difficult and frustrating part of this project was getting the helmet to fit comfortably using upholstery foam. Other guides on the internet show that they just use three blocks of foam cut into rectangles that you cram your head between, but that was unacceptable for me. I eventually figured out a good foam setup that leaves my ears uncovered, which is nice because it lets me hear and wear my glasses.
I hot glued everything together.
Electronics
The screen is made of 300 individually-addressable RGB LEDs, specifically WS2812Bs. I made the LED matrix from a single 5-meter, 60 LEDs/meter strip by cutting it into 15 strips of 20 pixels each and soldering them together. People often ask me how I can see through the helmet; the answer is that I designed the matrix to have empty space between the strips:
A Circuit Playground Express microcontroller (similar to an Arduino) controls the lights using a program I wrote. A mini PS/2 keyboard connects to the microcontroller through an adapter for an input method. This lets me control the lights. Just a few buttons would suffice for playing animations, but I opted for a full keyboard so I can type words to appear on the screen. The microcontroller has a built-in accelerometer which I use for a few gravity-sensitive animations.
Here's a circuit diagram of the whole thing. As with the other images on this page, click it for a bigger version.
Advice
Here are some lessons I learned and tips to anyone who might want to try making on of these.
- Make sure you get LED strips with black PCB, so they aren't visible through the tint.
- You can buy clips to attach ws2812 strips to each other without soldering, but beware! They might give an unreliable data pin connection, which can cause the matrix to glitch out and strobe.
- Of course, don't make your animations strobe on purpose either, or you might give someone a seizure.
- To conserve battery life and lower current requirements, try minimizing the amount of light your animations use. Program brightness adjustment too.
- Don't get hot glue in your hair.
- The level shifter apparently isn't necessary. The whole thing worked perfectly even when I accidentally used 3.3V everywhere instead of 5V, even the USB keyboard. It's probably a good idea to include it though.
- Try to keep the screen light so you don't strain your neck. Put the battery in the back to counterweight the screen.
- Cover logos on the monitor with something that gives it personality. In my case, the cute bow works well.
If you're trying to make your own TV head, feel free to ask me for advice! Send me a message on Mastodon or Twitter. (I should probably add an email address here too sometime.) If you don't need my advice, contact me anyway when you finish your TV head so you can show it to me!
Acknowledgements
Thanks to Franci Bolden for helping me with the dremel and bandsaw, and for insightful advice that I wouldn't have thought of! Also thanks to fuchsia and Izzy Swart for early hardware advice!
Gallery
Here are some more photos of the helmet in action.
Here's a video demonstrating the animations. The lights look a little small in this video because I had the brightness turned down.