Re: Accuracy of the FLIR

[Marc-Antoine Ruel]

http://www.pureengineering.com/projects/lepton

points to

https://drive.google.com/file/d/0B3wmCw6bdPqFblZsZ3l4SXM4R28/view

page 7:

Thermal sensitivity: <50 mK (0.050° C)

[Andrei Cosma]

Hi Mike,

Unfortunately, there is no answer for your question that will be in general true.

The values that the sensor reads from environment are let's say 99% accurate.
But, these values are not the real temperature of the object. The real value depends on: emission coefficient, reflections, and transmission.

Anyway, this may help you:
http://www.wired.com/2014/09/testing-accuracy-flir-one/
In some particular experimental settings, you can compute the accuracy, for a specific material (in that case water).

Best Regards,
Andrei

[Mike M.]

Hello

I am looking for a sensor with a Thermal sensitivity(NETD) of ~50mK , like the lepton,

and with a thermal accuracy of at least 0.5 °C.

Does anyone has an idea where can be find such a sensor.

Regards,

   Mike M.

[sa...@pureengineering.com]

If you have a shutter where you can measure the shutter temperate, then perform a FFC command, then you should get a thermal accuracy close to what you can measure the shutter at. 

for example the tmp006 thermipile has a .5 C accuracy.  you could use that to measure your shutter temperature. 

http://www.ti.com/lit/ds/symlink/tmp006.pdf

not sure of your exact application, but this is one option... 

[Mike M.]

Hello

Does anyone has an idea where can be found a sensor with an internal shutter which perform FFC 

with accuracy of at least 0.5 °C .

Maybe a new Lepton version.

Regards,

   Mike M.

[sa...@pureengineering.com]

The shuttered version of the lepton in now sold here

https://www.tindie.com/products/PureEngineering/flir-lepton-thermal-camera-breakout-2/

The shuttered version of the lepton automatically does a flat field correction on power-up and when needed(This calibrates the sensor, reduces noise, and gets rid of the lines reported on some of the sensors). Overall it produces better quality images. (The shutter can be removed if unneeded)

[Mike M.]

Hello

where should I place the thermipile to measure the shutter temperature to get accuracy of at least 0.5 °C .

Is the shutter is placed between the optics and the sensor or behind the optics.(there should be made some correction in measuring the shutter temperature because the optics

and some other Factors that may have some influence.)

Regards,

   Mike M.

[sa...@pureengineering.com]

the lepton with shutter has no space for a thermipile behind it.  I would use a thermipile to calibrate off any blackbody first. then once you know your reference temperature you can then do your accurate measurements. The calibration should be good as long as the lepton temperature is stable.