Thermal cameras are expensive. Even at low resolutions, it is not uncommon for a decent thermal camera to cost over $10,000. However, for only $20, you can buy an infrared thermometer that reads the average temperature over a small area. If we could turn that single area into a color and use a long exposure photography to "paint" the scene with that color, we could create something very similar to a proper thermal image.
This is not a new idea. The Public Laboratory has come out with a design for something that does this, but I have yet to see one make its way off of a breadboard. I decided to take the project to the next level and make a real, bona fide thermal flashlight. Here's how I did it.
Step 1: Materials
- Infrared Thermometer - MLX90614
- 0.1uF Ceramic Capacitor
- 2 4.7k Resistors
- 3 1k Resistors
- 8 RGB LEDs Note: Previously, and in the images in this instructable, you will see me using common cathode (negative) LEDs. To make your life easier with the transistors, use common anode LEDs like the ones now linked.
- Dorcy LED Flashlight
- 3 NPN Transistors
- Arduino, any will do
- 9V Battery Clip and Battery