32k pixel $250 Thermal Imager

That's cool, about 2% of the cost of our FLIR.

I'd expect you'd want the adjustable focus version to get close to a PC board.

The FLIR is really useful.

I suppose I should get a smart phone one of these years.

Yep, looks pretty handy.

I'd probably use it with a cheapie Android tablet. I've been doing a lot o f thermal stuff recently, waving an IR thermometer around.

That works pretty well but the SeeK looks more fun.

Cheers, James Arthur

The IR thermometers generally have a rotten field of view. The laser pointer makes you think you're scoping a point, when the gadget is actually averaging over a 30 degree cone... parallaxed way off the laser dot. The imagers are much better, and you can estimate the resolution from the image.

We're designing an RTD simulator box, and some super precise thinfilm resistors could fry if the customer connects us to a big power bus or something. So we're designing in an overload sensor that will open the circuit if it thinks our parts are being toasted. But where to set the limits? Do laser trimmed resistors have unpredictable hot spots? So we're launching a few stress tests on resistors, to set the spec limits and tune the shutdown circuits. One thing we plan to do is scope some resistors for hot-spot patterns, using the FLIR. It can resolve the hot spot on an 0603 resistor; you can basically touch a part with the lens and stay in focus. I think that germanium lens cost something like $3K.

It's great to look at a PCB and see what's hot. It's cool that they are getting affordable.

If you don't have a definite need for it, you don't need it.

I mentioned this to two friends who bought 'em. You can spend a few days looking at stuff, but then what? Resolution is way too low to look at small PCB hot spots. With the EBAY add-on lens it's a lot better,but still not very good. So, after a few weeks, they're both stuck in drawers somewhere.

Requires Android 4.4, I IIRC. Would have required me to buy a new phone...killed the deal for me. I'm waiting to see what FLIR has for their next gen of FLIR ONE. They will have to do an android version sooner or later.

If you need one, google to see if the actual useful resolution does what you need. Otherwise, it's a really cool toy to go in the drawer with all your other really cool toys.

It's a lot like owning a boat... What's better than owning a SEEK? Having two friends who own a SEEK!

I just spent several weeks doing a product with very exacting thermal requirements: a 3x5" 120W power supply--one switcher driving another-- closed box, no airflow.

I got the third try as input, which I measured at ~90c rise in still air. Not happy for a product that has to work in direct sun (Ta ~=55c), with potentially three boards in a small enclosure.

Besides just plain ol' bugs, the main problems were minimizing dissipation and improving the thermal paths. After refinement, dissipation is now about

Scanning with an IR thermometer at close (2 cm) range spotted some unexpected hot spots, but resolution was quite poor. :-)

Really? Here are some sot-23's, viewed with an external lens.

It's definitely crap. That's why I'm only offering $75 for either one of yo ur buddies' units. (Android, please.)

A $75 tablet is good enough. I got one for $35, dual-core, Android 4.4.

Cheers, James Arthur

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Yep. Pretty neat your FLIR can zoom in that close.

Even my IR thermometer was a lot more fun than epoxying thermocouples everywhere.

Cheers, James Arthur

I have a possible application for something like this in remote sensing. But we need a range in air of something like 1000 m or so. My impression is that at anything like 'normal' humidity, the IR absorbtion of the air ( water vapour ) is so high in the 10-1000 um region that all you see is a black wall.

Has anyone actual experience of doing IR imaging at that sort of range in air ?

I've not tried, but here's a two-minute YouTube of a test @ 120m, as a starting point.

Cheers, James Arthur

Normally that sort of thing is done in the 3-5 micron atmospheric window.

Cheers

Phil Hobbs

That guy is a mental midget.

I refuse to stoop that low.

Cheers, James Arthur

I too would be interested in one of those ( Android ) stuck away in a drawer somewhere. Just to try out an idea. The catch is it needs shipping to Australia. Willing to pay shipping both ways, just for a try.

Thanks Phil,

Might be worth a try then, although the temp range I am interested in is around 310 K, so the peak spectral emission is down in the 10 um range. But I gather water vapour is not too bad down there. Would also like to be able to find some real data on the absorbtion spectrum vs water vapour content.

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Data like this?

When looking for "Thermal Camera" videos on the SeeK unit I also saw lots of YouTubes showing shorter-wave IR conversions for ordinary video cameras. FYI.

Cheers, James Arthur

That plot is wrong--they've got the absorption depth in the far IR being le ss than a wavelength.

Plots of this are in all the standard places--they're probably in the Amazo n "search inside" page for the Wolfe/Zissis "Infrared Handbook".

Cheers

Phil Hobbs.

I'd guess that IR imagers are generally used at such short range that atmospheric absorption doesn't matter. For civilians anyhow.

It is interesting that liquid water and ice are dead black at thermal wavelengths. So a good check for an IR thermometer or imager is a cup full of hot or cold water. Set E=1.

Liquid water is black except in the human visible range. That makes sense, since our eyeballs are mostly full of water.

Kapton is black at imager wavelengths, so you can stick a bit of kapton tape to a shiny object to see its surface temperature.

It is cool that we can see the stars at night. Imagine living on a planet where you can't.

Cheers

Yes, I see the green curve in the graph is for water vapour. But at what concentration in air ?

I looked briefly at the HITRAN data, but that seems to be plotting individual line absorption, rather than total energy absorbtion. Probably there is much more there, but I dont see it - probably because I dont know enough about this area to look in the right places.

I should read those again.