RE: G-08 rebuild kit potential BOM

> http://www.extech.com/instrument/products/alpha/datasheets/IRC40data.pdf
> It states the Field of view is 17 deg. X 17 deg. and the min. focus
distance is
> 0.6m (2 ft.)

Oh, good lord... That would require trig. ;-) Uhhh... I think that's like a
~7"x7" field of view? One pixel every 0.09" or so? I guess that'd work for
some stuff on PCB's.

Wonder if there's any local reps that could do a demo for an hour or so so I
could play with it...

JohnR wrote:
> I was wondering if one could make a relatively inexpensive IR camera
> by using a Peltier cooler connected to a CCD element with an IR filter
> on the lens... As earlier design IR cameras needed to be cool to work,
> perhaps this would accomplish the goal?

Maybe? I kinda thought CCD's were sensitive in near infrared vs. mid/far
like thermography uses?

I think I read somewhere that the non-cooled arrays used now are actually
MEMS type sensors (so essentially mechanical elements that deflect when
'hit' by the far IR energy). Pretty cool. Reminds me of the little "spinny
thing in a lightbulb" gizmo that was always for sale at science museaums.
;-)

Most of the low cost stuff out there is intended towards building/plant
maintenance, power transmission, etc., so finding affordable units suitable
to look at a small area with high-ish resolution is tough. There's a fair
number of raw 'modules' out there that will give you an image (like the
various fire-fighting rescue systems and the like), but there's probably a
non-trivial amount of software that would have to be written to calibrate
each pixel and map its response as well as transform onto a known
temperature range... (I have *no* idea what you'd use for an accurate heat
source over a large surface area.) I suppose a "relative" temperature
gradient wouldn't be too hard, but I kinda want to be able to do point
measurement and say "this was XX, now it's YY" for some hard data.

There's some really nice ones out there that do stuff like export an entire
320x240 table of the sensor's field of view as an Excel spreadsheet with one
pixel per cell of temperature values down to 0.1C accuracy... So called
"research" units, but their pricing hits "new" SUV pricing pretty quick! I
think their annual calibration costs are probably more than that Extech
unit.

I suppose I could do home energy audits with it on the side to justify the
expense, but I mostly just want it for electronics work. ;-)

Surplus ones show up fairly regularly on eBay too, but it's easy to get
spoiled with the color LCD's, onscreen cursors, SD card data capture,
etc.... No free lunch. The older one usually have NTSC output from the
sensor and then you need to do a video capture of the data (and figure out
some software to go with it for analysis).

Ummmmm... Vector! (back on charter ;-)

-Clay

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Received on Sun Jul 27 03:33:17 2008