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Class I laser

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  1. Dec 15, 2015 #1
    I am doing some experimentation, for a science fair. And I want to make sure I the laser pointer I use is Class I (conceivably, I may change that, but any class of laser can be used to replicate results similar to the double slit experiment correct?). Can any one direct me as to where I may be able to get one? Are commercial laser pointers generally class 1?
    I could test them to see, by measuring output and all that, but I'd prefer not to go through that much effort if I can just get one that I know is of the correct class.

    Thank you for any help, and sorry if this is in the wrong sub-forum, I didn't see any more appropriate.
     
  2. jcsd
  3. Dec 15, 2015 #2
    Many laser pointers are class 2. I don't think I've ever seen something that was labeled class 1.
     
  4. Dec 15, 2015 #3

    berkeman

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    It looks like you are wanting to use a class 1 laser because it is the safest on the rating scale, right? https://en.wikipedia.org/wiki/Laser_safety

    If you cannot find a class 1 laser pointer, just use an optical attenuator to decrease the intensity of a class 2 laser pointer...
     
  5. Dec 15, 2015 #4

    Andy Resnick

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    AFAIK, laser pointers are class II or higher devices, I have never seen a class I laser.
     
  6. Dec 15, 2015 #5
    Class 1 means it's safe enough to look into, or it has enough engineering guards such that you can't look into it.
     
  7. Dec 15, 2015 #6

    Andy Resnick

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    Not exactly- a class I light source, defined by ANSI Z136, means it's safe to look directly into the beam for an indefinite amount of time (I believe the specific number is 8 hours). The sun is too bright to be a class I, and actually delimits between class II (eye aversion response is sufficient) and class III (injury possible). It's worth mentioning that I'm more familiar with the 'old' system rather then the 'new' system.
     
  8. Dec 15, 2015 #7

    boneh3ad

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    The new system is nearly the same. If I recall. Class 1 is safe for viewing intrabeam even with optical instruments. 1M is potentially dangerous if viewed trough magnification. With class 2 the blink reflex is safe to prevent hazard for light in the visible range and any emissions outside the visible spectrum must be class 1. 2M is the same as 2 but is a hazard if magnified. most laser pointers still go by the old system though, I believe.
     
    Last edited: Dec 16, 2015
  9. Dec 15, 2015 #8

    berkeman

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    So our OP seems to be MIA, but couldn't you make the science fair project a lot safer by attenuating the laser pointer beam? Heck, just use sunglasses to attenuate the beam. You still get an interference pattern, right?
     
  10. Dec 17, 2015 #9
    Sorry I did not get back to you. I want to use a Class I as it doesn't require paperwork for the science fair (and I'm allowed to bring it to the actual fair, without going through a long process). Would attenuating the laser pointer actually change the class? I'd assume altering the laser or strength enough would, correct?
     
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