Public Lab Research note

This is an upgrade for thermal-flashlight. Try building it and report back how it goes.

Common-anode LED thermal flashlight casing and circuit diagram

by lmc6399group | February 13, 2015 04:09 13 Feb 04:09 | #11580 | #11580

lmc6399group was awarded the Basic Barnstar by Rehanamark for their work in this research note.

A redrawn circuit diagram of the thermal flashlight described here:

If you follow their materials list under Build Your Own > parts list, you will be purchasing a mini-breadboard with no power rails which does not match up to their diagram. This diagram provides support for a breadboard with no power rails.

The 3 separate pieces connected only by wire (battery, breadboard, arduino) can be cumbersome to use as a flashlight. Our guide at the bottom of the page linked here provides instructions to build an external casing that holds everything together as a single unit with only the LED and thermometer exposed. The case still provides easy access to the circuitry if needed.

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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:

Really well done.

If you had to do three things to make your flashlight even better, what would you want to do?


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@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 to hold the LED/thermometer to a surface to detect temperature, we would have to add a lens over the LED to blend the RGB colors. We might also look into adding a display of the specific temperature or interface for the user to specify the threshold temperatures at which the LED reacts.

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