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Thread: Laser Power Meters

  1. #1
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    Default Laser Power Meters

    Thanks for all the help so far. I am learning learning. Thanks for your patience?

    What laser power meters are people using? Any possibility of getting one that is reliable and accurate and isn't super expensive?

    Wes

  2. #2
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    What do you want to use it for?
    Static power testing on a bench? In the field? Logging facility?
    http://www.facebook.com/SubsonicSystems
    http://www.frikkinlazors.co.uk

    You are using Bonetti's defense against me, ah?

    I thought it fitting, considering the rocky terrain.

  3. #3
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    In the field, no need for a logging facility. Readable displayin a dim room is useful.

    W.

  4. #4
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    Default

    There was one in the B/S/T section posted in the last few days.
    I think they wanted $95 for it, and did up to a couple of watts; might be worth a look.
    - There is no such word as "can't" -
    - 60% of the time it works every time -

  5. #5
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    Is this to measure if beams are above MPE in a show situation. E.g. Need good accuracy in the 0 to 10mW range?
    http://www.facebook.com/SubsonicSystems
    http://www.frikkinlazors.co.uk

    You are using Bonetti's defense against me, ah?

    I thought it fitting, considering the rocky terrain.

  6. #6
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    Yes, to measure MPE. What do you think of the Radiant Electronics X4 3.7W Laser Power Meter?
    https://illuminationsupply.com/radia...l#.UvPCKEJdVUM

    Wes

  7. #7
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    How do you want to do your MPE calcs I suppose is the next question?

    If you want to actually measure a beam at the audience and have it show MPE or below then you are talking about a meter that can display accurately under 10mW
    Most cheaper thermopile based meters do not do this, but some do have known characteristics that you can exploit

    As an example, if your sensor is 10mm^2 then assuming you have no scanfail (why are you crowd scanning??) you need to be able to show <=2.5mW on the meter (with the sensor completely filled)

    You could go the calculation route and measure beam properties and maximum power, and work out the total irradiance from that.
    http://www.facebook.com/SubsonicSystems
    http://www.frikkinlazors.co.uk

    You are using Bonetti's defense against me, ah?

    I thought it fitting, considering the rocky terrain.

  8. #8
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    Santa Cruz, CA
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    Default

    I'm working off of this ILDA doc: http://www.laserist.org/files/audien...iew_latest.pdf

    Murphy and Makhov's suggestion is that crowd scanning always be measured.

    Are you suggesting that the X4 doesn't have the resolution to measure low-end power settings, such as in audience scanning situations?

    Can you suggest another low-cost LPM that is more suited for that?

    W.

  9. #9
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    Are you suggesting that the X4 doesn't have the resolution to measure low-end power settings, such as in audience scanning situations?
    I can't comment on the X4, but experience suggests that budget thermopiles designed to measure multiple watts are not going to give you the resolution you require at less than 5mW

    I don't think that 'low cost' and this sort of performance go hand in hand tbh.

    Murphy and Makhov's suggestion is that crowd scanning always be measured.
    As I said, there are other ways of knowing the irradiance, providing you can measure total output 'fairly' accurately and beam dimensions pretty accurately.

    You can then do the sums, or use something like the very excellent Laser Show Safety app from LVR Ltd - James Stewart on the forum (iPhone, not sure if he's done other platforms yet) to do the calculations.

    In fact, the app will probably give you a fairly good idea of whether you will be able to crowd scan in your given scenario, even using typical beam specs for the laser you have.
    http://www.facebook.com/SubsonicSystems
    http://www.frikkinlazors.co.uk

    You are using Bonetti's defense against me, ah?

    I thought it fitting, considering the rocky terrain.

  10. #10
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    Default

    Do you have a link to the Last Show Safety App?

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