Fast Response - Contactless Thermometer to Arduino

Hi,

I looking for a fast response ( 1 ms or less) contactless (laser or IR) Thermometer that can accurately measure surface temperature of a wire (0.5mm diameter).

Does anyone have any ideas as to where to look? What company? etc...

Thanks

Have a look at this : Infrared Thermometer - MLX90614 - SEN-09570 - SparkFun Electronics

Price is a bit high, but you can probably find it much, much, much cheaper elsewhere. But then again, SparkFun need our money, right?

Thanks for the response Billo,

This is a good part, but I was looking for something that can measure surface temp of a wire o.5 mm diameter. This part is not suitable for this. Also I did not find the response time for it.

Thanks,

Whichever sensor you get, for your application you are going to need to build optics.
For something similar recently I found a solution but the sensing assembly element was 250+.
Hacking a cheap ir thermometer may be a more affordable option.

I think, for the actual sensor, the response is pretty close to real-time. As for their electronics, I don't know. I didn't study the specsheet so don't know if they give any clue. I could see it taking more than 1ms to assimilate the signal from the sensor and process it into a PWM signal though.

As for the ability to monitor a thin wire, that's what lenses are for, right?

I kinda need a off the shelf part.
I would imagine building optics would cost more than that.
Could you give the part for your 'solution'?

Thanks

My solution is for a 2 colour pyrometer for furnace use which is similar but unsuitable for your purpose.

Google search words to try :- infrared, pyrometer, spot focus, close focus, module , detector. industrial sensors or controls.

I think what you need is a close focus infrared thermometer/detector.

built handheld units can be found on the web
I have 40 UKP one from maplins.
I have not been able to find a standalone module however, I think its just a case of googling until you find one
Explanations here.

edit
Measurement of spot temperature is not uncommon, measurement of 0.5 mm spot size is.

Good luck

Amazing,
browser suggestions just popped this up

Wow man... you rock!!!

I cant find the datasheet for this thing though... what is the response time of this thing?

All they seem to have is a small specsheet: http://www.everestinterscience.com/pdfspecifications/Vario-Therm%206000L/Vario-Therm%206000L%20Spec.pdf

Response time is 0.1 seconds.

I kinda need the response time to be 1 ms or less.
I have system that changes temperature from room temp to 100 Degrees C in about 100 ms. Then it cools back down to room temp in 3 to 4 seconds. I want to be able to record this change of temperature.
So a response time of 100 ms is kind of useless!

I was searching online about only the response time... Does any company make non contact digital sensors with 1 ms response time???

Thanks

Apologies, I read/understood that as 1s , it was a bit unexpected.

Fast temperature measurement is possible at microsecond or even nanosecond response time but it's a bit esoteric.
Sensors tend to need cryogenic cooling from memory , technology may have improved faster more than my memory.

Wikki on bolometer or microbolometer.

This may seem a bit oddball but try asking in an astronomy forum , if commercial devices are available they may know.

I have forgotten all the calculations to do the math, but you could use 3 photomultiplier tubes, each with a different frequency of IR filter in front of it to determine temperature. The idea is to determine the parameters of the Boltzmann state distribution from which an accurate determination of the temperature can be made. This technique is good for sub-nanosecond temperature readings, although not real-time. We'd collect the data real-time, but analyze it later. However, back in 197X we did not have the computing power we have today. I fee sure that with an array of 3 properly chosen and filtered photo transistors or PIN diodes, appropriate amplifiers and an Arduino Due you could do accurate temperature readings in a few microseconds.

Might be a bit out of scope though.

So, what is this device with the 0.5mm wire anyway, and why can't you make contact with it?

That is exactly how 2 colour pyrometers work, 5 colour are available commercialy which give results in near real time today but as they all seem to use pyroelectric sensors they will not give the required speed.

I think the best bet would be to follow the link I gave or similar and ask the companies who know the industry.

This one just popped up 4/9 mS.

I have noticed that the commercial units are too clever by half and include processing in the response time.
Possibly if you can get a raw sensor you could improve it by aquire and post process.

FardinB:
I kinda need the response time to be 1 ms or less.
I have system that changes temperature from room temp to 100 Degrees C in about 100 ms. Then it cools back down to room temp in 3 to 4 seconds. I want to be able to record this change of temperature.
So a response time of 100 ms is kind of useless!

I was searching online about only the response time... Does any company make non contact digital sensors with 1 ms response time???

Thanks

It would be great to know exactly what this system is and what you intend to do with the recorded information. If you just need to make a plot of the temperature curve, then this can be done later by analyzing data that can be recorded during the event. If you need to respond to the system at a particular temperature and take some action, then there may be a better was to do this than to get an actual temperature reading on some arbitrary scale.

The temperature of any system can be determined in many ways. In fact, temperature is never directly measured, but something else is, and a conversion to temperature is made. For example, a mercury thermometer uses the expansion of liquid mercury to give an estimation of the temperature. The system I described above used the emission spectrum of a gas to determine the temperature of that gas. I worked on another project once that monitored the resistance of a platinum wire to determine the temperature inside an engine combustion chamber.

Let us now more about the system and what the recorded temperature data is needed for and we may be able to help better.

Yes more information the better.

Thinking on, thermopiles are probably too slow for your requirement.

For a plain sensor you could look at this, 5 uSec and inbuilt peltier cooler so no need to use cyro.

unfortunately its an OEM thing so you would have to do your own optics.
This may be easier than you think, get a copy of Edmund optics catalogue, they used to have a very good explanation in the back.

edit
missed link

http://www.osioptoelectronics.com/standard-products/silicon-photodiodes/two-color-sandwich-detectors.aspx

edit

Drawing graphs of my gadget which is sub millisecond ,I realised something.
If you just want a graph you may not need 1 mS accuracy.

Using the link I posted, it has analogue output , sample it at 1ms intervals and provided you have stable endpoints you can correct the graph later by shifting the x axis.

This will not work however on a device which digitally processes , it has to be analogue so you can control the sampling.

Hi Billo and BoardBurner,

Thank you guys for your responses.
So here is what the system is about.
First you have to know what this is: Shape-memory alloy - Wikipedia
what I am doing is testing a piece of this material to find a very high cycle behavior like (100,000 cycles)
I am heating the wire electrically using 14 A in less than 100 ms from room temp to 100 degrees C.
right now we have position and force feedback which are used for control. I want to add temperature to the system not as feedback but just raw data to be analyzed later( hence NO processing).
the position and force are working and logging and analyzing fine. My problem is a temperature sensor (non contact).

To answer Billo question about why noncontact? I do not want to take out heat from the wire, no matter how small, because if I take out heat, then it will change the behavior of the wire.

I have consulted this page which has a list of all companies that manufacture IR temp sensors: http://www.directindustry.com/industrial-manufacturer/infrared-temperature-sensor-71767.html
I came across this which has the closest match to what I am looking for: http://www.micro-epsilon.com/temperature-sensors/thermoMETER_CT_basic/thermoMETER_CTfast/index.html
its the same company that Boardburner mentioned.
what I am exactly looking for are these specs:

  • fast response (1 ms or less) (under 10ms is OK too)
  • measurement of spot size of 0.5 mm
  • measurement range of 0 to 200 degrees C
  • 0 to 5V analog OR digital output to be read by microcontroller.

Also I think using photomultiplier and kinda making my own sensor would become too costly and not very accurate...

Thank you,

FardinB:
Hi Billo and BoardBurner,

epsilon.com/temperature-sensors/thermoMETER_CT_basic/thermoMETER_CTfast/index.html

Also I think using photomultiplier and kinda making my own sensor would become too costly and not very accurate...

Thank you,

I think that is the same one with different optics.
CF25 looks ideal, 0.5 mm spot at 8mm.

I was not sure before but It sounds as though you are doing research with a decent budget for bits.

If it were me, I'd fore go the whole optical thing. In this case, I'd measure the current through the wire and use that to calculate the temperature. If the resistance/temperature coefficient is not known (and that would surprise me) you can determine it experimentally. This would give you the most accurate determination of the temperature as it is the current that is creating the change in temperature.

Here is a paper that goes into using the resistance to determine the temperature and as a feed-back mechanism: http://www.ndt.net/article/ndtcanada2011/papers/66_Gorbet_Rev2.pdf