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Infrared laser question

  1. Oct 26, 2014 #1
    I am thinking about a possible experiment, and would like to measure the temperature of gas in various places inside of a glass enclosure. Is it possible to use an infrared laser to this? Thanks
  2. jcsd
  3. Oct 26, 2014 #2


    Staff: Mentor

    Does the gas you are interested in have different IR wavelength absorption characteristics as a function of temperature, or does it scatter IR light well? Is the mass and composition of the gas known?
  4. Oct 26, 2014 #3


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    Staff Emeritus
    Science Advisor
    Education Advisor

    Not sure what you mean by "infrared laser" or how you think that will give you a measure of the temperature. Could you mean the non-contact IR thermometers that are being sold commercially? If you really, truly mean an IR laser, please be aware of a safety hazard with such a device, especially to your eyes.

    You also need to make sure that if you are using such a device that the window of the vessel containing the gas is IR transparent. Otherwise, you measure a nonsensical number.

  5. Oct 27, 2014 #4
    Thanks for the replies, sorry I am a little late here... I am curious about testing hydrogen gas. I was thinking about the infra red non contact thermometers, yes, you are right Zapper Z. But I think those can only be measured on a surface, is that correct? If I used a real IR laser, could it read a certain point and a certain depth inside the glass? I am thinking about a low density gas.
  6. Oct 28, 2014 #5


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    Staff: Mentor

    IR thermometers detect infrared radiation, IR lasers emit infrared radiation.

    Hydrogen gas basically neither absorbs nor emits in the infrared part of the spectrum.
  7. Oct 28, 2014 #6
    Dr. Claude, thank you for posting... !!!
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