Inspired by the Public Laboratory and having just finished a round of college applications, I decided to experiment with thermal imaging on the cheap.
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.
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.
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Signing UpStep 1: Materials
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
- Perfboard
![PLAE - Portable Led Angel Eyes [ +1000lm ]](http://www.instructables.com/files/deriv/FAU/PMIX/GWHN3OBW/FAUPMIXGWHN3OBW.SQUARE.jpg)
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For 8 LEDs, you want something that can drive at least 8 x 20 = 160 mA per colour so a standard 2N3904 (200mA) per channel should be fine. My guess is that it will be much brighter using these because the Arduino is probably limiting your current at the moment.
Hope I'm not just being dense and missing something in the write-up!
Fab' project BTW.
Ugi.
That should give you the idea.
Ugi
Ugi
You should get a single ATMega for that function (it'll probably just cost you a couple of dollars over there), use the Arduino to program it, then take it out and connect it to your perfboard.
See http://arduino.cc/en/Tutorial/ArduinoToBreadboard for an example of how to do this, and http://arduino.cc/en/Hacking/PinMapping168 for the corresponding uC pins to connect to.
(I still need to learn how to make a dedicated processor and am looking forward to learning how to make this with the ATMega chip previously mentioned.)
However, it appears the people that already "know about Thermal measurement" are the ones jumping up and down in joy.
For the rest of us,,,,, well,,,,, after spending some time investigating now I understand the theory and purpose.
So, question #1: do I also need a camera? which type of film?
question #2: does this work if I point it to my house at night and see the thermal situation? or is it too large an object for this device?
As somebody else suggested, you need to explain the theory and purpose, the construction (you did), and the practical application or usage of your ‘able.
Otherwise it is like “preaching to the choir”, everybody else may be left out….
could anyone describe, if you have done it, the experience in doing a full external house thermal study? That would be of great help and enticement.
If you could document it with some pics or video, great.
http://www.blackanddecker.com/power-tools/TLD100.aspx#
The thermal flashlight produces a gradation of colors. The Black and Decker device is either red or blue. If you look at the main image of this post, it would be impossible to reproduce with the Black and Decker device -- there are simply far too many colors. The B&D device also has a much more narrow beam.
For years I was thinking of doing something similar - but using an X-Y stepper controlled carrier that would have a an MLX90614 mounted in a tube, staring forward, and build an IR image by raster scanning, but this is a lot simpler.
If someone can find a good source of IR-transparent Fresnel lenses, you could greatly increase the resolution..
Again, Great project and nice description.
Great Job! I will definitely make one!
I like the simplicity of it: Just point at a thing and see the color of illumination to determine the temperature. Sweet!
Also an idea here: If you add a paper-tube on the sensor, it gets a more narrow field of view and you can pinpoint it better.
Add a laser-dot or laser-cross (4$ @ http://dx.com/p/red-laser-module-focused-cross-3-5v-4-5v-16mm-5mw-5942) and you can even point the things you want to measure. However, be sure you dial the power down on the laser...