How do I make a VERY sensitive thermopile?

Question

Like, one that could sense radiant heat coming off of your body a few inches away. I need it so I can compare the amount of heat generated by several lasers. I am gonna put it behind a thin, black surface (I don't know what yet) and compare the voltage generated. Any tips would help!

THANKS!

Answer 1

If you need a VERY sensitive thermopile, I'd suggest buying one premade from somewhere like digikey.com. Then, calibrate it with some known temperatures so you can derive a formula to get temperature from volts.

Answer 2

I would try and find the right lens and focal length. You need to focus the light in on the tip of the thermopile.

As far as I know you use a lot of thermocouples in series to add their induced mV signals to a bigger signal. Then you amplify the signal to get a useable output.

To calibrate just focus on a known heat source and then another of a different temp. Then take a few other readings and check.