+ Reply to Thread
Page 1 of 2 1 2 LastLast
Results 1 to 10 of 12

Thread: Optical intelligent O2 sensor

  1. #1
    DOH! 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68's Avatar
    Join Date
    Jan 2009
    Location
    Columbia Heights, MN
    Posts
    1,024
    IDA72 - sorrta

    Optical intelligent O2 sensor

    This sensor is used in the beer industry, so it must be a good thing!
    It looks relatively adaptable, with a little creativity.



    Principle
    The optical oxygen sensors are based on an optical detection
    method, the so called fluorescence quenching.
    Here is a short summary of the principle. In contrast to
    the polarographic Clark-electrode, which detects a redox
    reaction of oxygen at the electrode, the new optical
    method is based on an energy transfer between a chromophore
    and oxygen.
    – A chromophore, embedded in the sensor tip is illuminated
    with blue light. This chromophore absorbs the
    energy and if no oxygen is present emits red fluorescence
    light with a specific lifetime. This emitted light
    is being detected by a detector in the sensor head.
    – In the presence of oxygen, the chromophore transfers
    the energy to the oxygen molecule. Oxygen is then
    able to transfer this energy as heat to the surrounding
    area and no fluorescence is emitted.
    – The total intensity of the fluorescence and the lifetime
    of the fluorescence is related to the Oxygen partial
    pressure in the medium.
    – To analyze the lifetime of the fluorescence, the excitation
    light is pulsed with a constant frequency, the
    emitted light shows the same course but with a time
    delay to the excitation. This delay is called Phase shift
    or Phase angle (Phi).
    – The sensor InPro 6880 i /6870i /6970i detects this
    time delay and calculates the oxygen concentration.

    – The oxygen value is digitally transferred to the transmitter.

    The rest can be found here:
    InPro6870i (Optical Oxygen Measurement System) - NEW! - METTLER TOLEDO - United States


    Have fun,
    Hunter

    Last edited by 19Hunter68; 16th January 2010 at 16:23.

  2. #2
    New Member
    saveourseas has a brilliant future saveourseas has a brilliant future saveourseas has a brilliant future saveourseas has a brilliant future saveourseas has a brilliant future saveourseas has a brilliant future saveourseas has a brilliant future saveourseas has a brilliant future saveourseas has a brilliant future saveourseas has a brilliant future saveourseas has a brilliant future saveourseas's Avatar
    Join Date
    May 2005
    Location
    New York NY, Los Angeles CA, Dallas TX
    Posts
    713
    Mk15.5, Prism, Prism2

    Ray, Dolphin, Mk15

    Re: Optical intelligent O2 sensor

    Do you know how and where it is used in the process?
    Sometimes, devices using light can have problems with high RH in the gas, such as CO2. From what is said though it is using a blue light which might indicate a long wavelength light which could have less issues with scattering.
    What is the power requirements and consumption?
    "However beautiful the strategy, you should occasionally look at the results." Winston Churchill
    A is A

  3. #3
    DOH! 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68's Avatar
    Join Date
    Jan 2009
    Location
    Columbia Heights, MN
    Posts
    1,024
    IDA72 - sorrta

    Re: Optical intelligent O2 sensor

    Here are the specs. It is used submerged in the beer, but, seems like it will work in open air.
    Attached Files

  4. #4
    DOH! 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68 is a splendid one to behold 19Hunter68's Avatar
    Join Date
    Jan 2009
    Location
    Columbia Heights, MN
    Posts
    1,024
    IDA72 - sorrta

    Re: Optical intelligent O2 sensor

    Specs on the M400 computer (IP65 rated)
    and specs on the CO2 sensor that can be incorporated.

    It will take some work, but, its a start.
    Last edited by 19Hunter68; 16th January 2010 at 18:47.

  5. #5
    RBW Member MatV is a jewel in the rough MatV is a jewel in the rough MatV is a jewel in the rough MatV is a jewel in the rough MatV is a jewel in the rough MatV is a jewel in the rough MatV is a jewel in the rough MatV's Avatar
    Join Date
    Feb 2007
    Location
    Germany, Schleswig-Holstein
    Posts
    360

    Re: Optical intelligent O2 sensor

    Quote Originally Posted by 19Hunter68  View Original Post
    – A chromophore, embedded in the sensor tip is illuminated
    with blue light. This chromophore absorbs the
    energy and if no oxygen is present emits red fluorescence
    light with a specific lifetime. This emitted light
    is being detected by a detector in the sensor head.
    – In the presence of oxygen, the chromophore transfers
    the energy to the oxygen molecule. Oxygen is then
    able to transfer this energy as heat to the surrounding
    area and no fluorescence is emitted.

    What worries me a bit, is the reciproke correlation between oxygen partial pressure and the detectable phenomena.
    This means to me, the higher the ppO2, the higher the error in measurement.
    Mat

  6. #6
    Tobin George cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52 is a splendid one to behold cool_hardware52's Avatar
    Join Date
    Mar 2005
    Location
    SoCal USA
    Posts
    1,113

    Re: Optical intelligent O2 sensor

    Quote Originally Posted by 19Hunter68  View Original Post
    It is used submerged in the beer,
    My guess is there will be no problem finding volunteers to test such a device.

    Tobin

  7. #7

    Re: Optical intelligent O2 sensor

    Quote Originally Posted by 19Hunter68  View Original Post

    – A chromophore, embedded in the sensor tip is illuminated
    with blue light. This chromophore absorbs the
    energy and if no oxygen is present emits red fluorescence
    light with a specific lifetime. This emitted light
    is being detected by a detector in the sensor head.
    – In the presence of oxygen, the chromophore transfers
    the energy to the oxygen molecule. Oxygen is then
    able to transfer this energy as heat to the surrounding
    area and no fluorescence is emitted.
    – The total intensity of the fluorescence and the lifetime
    of the fluorescence is related to the Oxygen partial
    pressure in the medium.
    – To analyze the lifetime of the fluorescence, the excitation
    light is pulsed with a constant frequency, the
    emitted light shows the same course but with a time
    delay to the excitation. This delay is called Phase shift
    or Phase angle (Phi).
    – The sensor InPro 6880 i /6870i /6970i detects this
    time delay and calculates the oxygen concentration.
    – The oxygen value is digitally transferred to the transmitter.
    They have a siginificant temperature dependancy - indeed I have used the same technique for temperature measurement (in a microwave field where you cannot use thermocouples or thermistors because they act as antenna). You can get similar sensors for CO2 detection. Both types are not suitable for atmospheric gas sensing more like dissolved gases.

    If the O2 sensor is anything like the fluoroptic thermometer I used, they are power hungry and fairly fragile. As another poster remarked, the sensitivity is highly non linear.

  8. #8
    RBW Member trakrat is on a distinguished road trakrat is on a distinguished road trakrat's Avatar
    Join Date
    Oct 2008
    Location
    the peoples republic of yorkshire
    Posts
    164
    rEvo

    Re: Optical intelligent O2 sensor

    i wouldn't swear to it but i seem to think i read something about the speed of these being too slow for use in rebreathers!

  9. #9
    RBW Member Snusmumrik will become famous soon enough Snusmumrik will become famous soon enough Snusmumrik will become famous soon enough Snusmumrik's Avatar
    Join Date
    Nov 2008
    Location
    St.Petersburg, Russia
    Posts
    207
    IDA-71(KISS Mod)

    IDA-59 O2 Mod & KISS, IDA-72

    Re: Optical intelligent O2 sensor

    Best response time was less than 20 seconds to 98%,
    more common - less than 90 seconds. Too slow for rebreathers,
    by my opinion.

  10. #10
    RBW Member RedDucati will become famous soon enough RedDucati will become famous soon enough RedDucati will become famous soon enough RedDucati will become famous soon enough RedDucati's Avatar
    Join Date
    Jan 2009
    Location
    Dallas
    Posts
    188

    Re: Optical intelligent O2 sensor

    Good idea, keep thinking Hunter.

    Tyler

+ Reply to Thread
Page 1 of 2 1 2 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts