Thermal Flashlight
thermal-flashlight

A "Thermal Flashlight" is a DIY device which lets you do a kind of "light painting" -- [thermal photography](/wiki/thermal-photography). It produces a colored "heat map" overlaid directly onto a photo of a room. This is the simplest, cheapest, and to date, most effective way we have developed of measuring heat leaks or cool leaks indoors and outdoors. Simply put, the "flashlight" puts out redder light if it's pointed at something hot (default 75 deg F or more) and bluer light if it's pointed at something cold *(default 60 deg F or less). ### Parts The Melexis MLX90614 digital thermometer used in this kit can be found in a few places, at different price points: * [Adafruit.com](https://www.adafruit.com/product/1747) * [AliBaba.com](https://www.alibaba.com/trade/search?fsb=y&IndexArea=product_en&CatId=&SearchText=Melexis+MLX90614+3V&viewtype=) ### Assembly There are a few versions of the thermal flashlight: [notes:grid:activity:thermal-flashlight-assembly] ### Questions [questions:thermal-flashlight] **** ### Activities [activities:thermal-flashlight] **** ### Using a Thermal Flashlight To capture the light painting over time, we have been using timelapse photography or this [p5js.org sketch](https://editor.p5js.org/jywarren/present/dl7B2Upp-) ([source](https://editor.p5js.org/jywarren/sketches/dl7B2Upp-)) (or its inspiration, GlowDoodle), as seen in the top image on this page. * Within view of the camera or laptop, sweep the flashlight beam over the scene at a distance of about 12 inches. * Try to stay out of the way of the beam, and don't point it directly at the camera or it will create a "starburst" and may mess up your image. * It's helpful to wear dark clothing so you don't show up in the image as you're moving around. ### Building your own **Parts list** For a Thermal Flashlight with 3.6 V Melexis Sensor and Common Anode LED. * 1 [Melexis MLX90614](http://www.futureelectronics.com/en/technologies/semiconductors/analog/sensors/temperature/Pages/6314181-MLX90614ESF-DAA.aspx) non-contact IR thermometer (3v). Data sheet: http://www1.futureelectronics.com/doc/MELEXIS/MLX90614ESF-DAA.pdf * 1 [common-anode RGB LED](http://www.sparkfun.com/products/10820) * 2 4.7k Ohm resistors * 2 100 Ohm resistors * 1 180 Ohm resistor * 1 0.1 μF capacitor * wire * [a breadboard](http://www.sparkfun.com/products/7916) or circuit board & soldering eqmt. * [Arduino](http://arduino.cc) * 9v battery and holder **Software** thermal-flashlight.zip Gist: https://gist.github.com/sdosemagen/1739961/ _Note: The goal of this file is to be a place to download everything without pursuing other links. If there are changes or updates please feel free to add and re-upload. If the file is missing anything, please comment below. You might notice that this is for the 5v Melexis, but it will work for either without issues. Alternative variations of the Flashlight can be made with a 5.5V Melexis Sensor and Common Cathode LED. For the 5.5 V sensor follow this diagram: http://publiclaboratory.org/notes/sara/2-7-2012/circuit-diagram-5v-melexis-sensor For the common cathode circuit board follow this diagram: http://publiclaboratory.org/notes/warren/2-11-2012/common-cathode-variant-thermal-flashlight-code Links to purchasing equipment: ### Consumable Parts * LEDs (1 per flashlight, but they sell as a pack of 25): http://www.sparkfun.com/products/10818 * Arduino Uno (1 per flashlight): http://www.sparkfun.com/products/11021 * Capicator (1 per flashlight): http://www.sparkfun.com/products/8375 * Resistor pack (this pack has a 180 ohm resistor which we found other packs not to have): http://www.eio.com/p-19326-velleman-kres-e12-pack-of-610-e12-series-resistors.aspx * 3.6 V infra red thermometer (1 per flashlight): http://www.futureelectronics.com/en/technologies/semiconductors/analog/sensors/temperature/Pages/6314181-MLX90614ESF-DAA.aspx. Data sheet: http://www1.futureelectronics.com/doc/MELEXIS/MLX90614ESF-DAA.pdf If you are starting an electronics kit from scratch: * a 40Watt soldering Iron (if you want it to be permanent otherwise duct tape or Velcro works temporarily) * hookup wire (solid not stranded- 22 or 24 gauge, you can get this at Radio Shack) * pliers called "wire strippers" to get the plastic wrap off the hookup wire (can get at Radio Shack) * solder for 40Watt iron, lead-free. * a breadboard (1 per flashlight). If you aren't soldering: http://www.adafruit.com/products/64. If you are soldering: https://www.adafruit.com/products/571. * a USB cable to connect the arduino to the computer via USB for power 5Volts (can get at Radio Shack) * household sponge for cleaning solder off tip * 9 volt battery with connector wires (can get at Radio Shack- 1 per flashlight) ***Cost: ~$40-$60*** **** ### Updates All research on PublicLab.org about the thermal flashlight project: [notes:thermal-flashlight] **** Several meetups have been organized to build and test thermal flashlights, at RISD (Providence, RI) and in Brooklyn, NY. We are organizing one now in Somerville, MA: * [Thermal Flashlight workshop](/wiki/thermal-flashlight-workshop) * [May 26 AS220 workshop](http://publiclab.org/wiki/may-26th-as220-thermal-flashlight-workshop) * [Thermal Fishing Bob presentation from NE barnraising](http://publiclab.org/notes/Kaya9804/06-09-2014/thermal-fishing-bob-presentation-from-the-ne-barnraising) ## Thermal flashlight heatmaps **** ## Custom thermal flashlight circuit boards Instead of building off of an #Arduino, it's possible to make a Thermal Flashlight using a custom circuit board. The circuit board files can be found here: https://github.com/Pioneer-Valley-Open-Science/thermal-flashlight ##Photos [![IMG_0779.JPG](https://i.publiclab.org/system/images/photos/000/003/132/medium/IMG_0779.JPG)](https://i.publiclab.org/system/images/photos/000/003/132/original/IMG_0779.JPG) [![IMG_0781.JPG](https://i.publiclab.org/system/images/photos/000/003/133/medium/IMG_0781.JPG)](https://i.publiclab.org/system/images/photos/000/003/133/original/IMG_0781.JPG) ...


Author Comment Last activity Moderation
printers "Thanks so much for posting this note! Click Now " | Read more » almost 3 years ago
liz "hi! 7 years later, i tagged this post with thermal-flashlight :))) " | Read more » almost 3 years ago
warren " Quick update based on https://gist.github.com/jywarren/1ad7dd997b6319ccb2525958709125ab Using this library! https://learn.adafruit.com/using-mel..." | Read more » over 3 years ago
liz "Wow! Just discovered this great project. Did you take any photos or timelapse photos of the colored light cast by the thermal flashlight? Would be ..." | Read more » about 4 years ago
tommaso_miori "Hi, I am not quite sure about the working principle by which the presence of water is detected. I believe that is due to water absorption @ a speci..." | Read more » about 4 years ago
samrider "@sekjal. I was amazed by the use of Lego. I wanted to ask you if it was possible to make a wall riding car similar to one shown by @Mathew or this ..." | Read more » over 4 years ago
jsyedali8 "How to draw a circuit diagram like this..? Which Software can be used to draw, Suggestions Please.. " | Read more » over 4 years ago
jsyedali8 "How to draw a circuit diagram like this..? Which Software can be used to draw, Suggestions Please.. " | Read more » over 4 years ago
jsyedali8 "How to draw a circuit diagram like this..? Which Software can be used to draw, Suggestions Please.. " | Read more » over 4 years ago
pikit688 "How to connect camera ? " | Read more » about 5 years ago
jfd "Hi, great discussion. Probably the best thing here would be for us to build our own custom board including a high speed interface for capturing str..." | Read more » almost 6 years ago
warren "Hi, did you mean for this project? https://publiclab.org/wiki/thermal-photography " | Read more » almost 6 years ago
vwls "Hi @SCG! I realize this post is two years old, but would you be willing to share links to hardware and software documentation? I'm looking at a f..." | Read more » almost 6 years ago
switchmod3 "Hi @ajawitz, Do you happen to have a binary dump of the EEPROM that's on the Radio Shack pocket IR thermometer? My unit is spitting out an "Er 5" ..." | Read more » about 7 years ago
kgrevera "I will be attending! " | Read more » over 7 years ago
neilhendrick "I will be attending! " | Read more » over 7 years ago
kgrevera "I will be attending! " | Read more » over 7 years ago
warren "So, does priority date allow them to back-date the effective date of their patent to before we independently published? I guess I thought "first to..." | Read more » over 7 years ago
lmc6399group "@cfastie We would probably add a gradient of colors (in the code) to indicate more varied temperatures than just hot/cold. Given how close we have ..." | Read more » over 7 years ago
mathew " " | Read more » over 7 years ago
cfastie "This is the best story ever of jumping into a Public Lab tool and making it better. This great video should be embedded in the research note above:..." | Read more » over 7 years ago
gbathree "I'm also very curious to see how this progresses. " | Read more » over 7 years ago
warren "Here are some potentially helpful notes from OSHWA: http://www.oshwa.org/2013/12/05/open-hardware-legal-meetup-nyu-nov-11/ " | Read more » over 7 years ago
donblair "I myself am really curious about this issue in general, especially as I dive more into developing open environmental monitoring hardware :) Maybe ..." | Read more » over 7 years ago