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I need help

  1. Jul 6, 2005 #1
    I want to know if its possible for me without any sofisticated tools to make the split needed for the interference experiment? I have a laserpoiner that as the the source of light. I have tried to make the split by cutting the back part of a mirror with a smal raizorblade. But it seems that the cut isnt small enought. Is this possible, and if so what do i need to do?
  2. jcsd
  3. Jul 6, 2005 #2


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    Last edited: Jul 6, 2005
  4. Jul 6, 2005 #3
    Hi there,

    This is more than possible with a laser pointer and any old collection of household goods.

    I remember when I was doing GCSE's (exams in the UK when you are 14/15), observing interference effects by shining a laser pointer at the gap formed between two 3.5" disk covers. You will get inteference effects off one slit, no need for two. Try a spacing of one foot between the pointer and slit, and one foot between slit and screen. Push the two objects forming the slit slowly together (ensuring that the slit is illuminated fully by the pointer - they are invariably crap lasers so this shouldn't be a problem) until you see an inteference pattern.

    Best of luck, and please report back - it's amazing when you first make it (and see it) for yourself.

    Next step - making holograms :-)

    James Jackson.
  5. Jul 8, 2005 #4
    dont work.

    It just cant be done, dont matter how you want to put it, to get interference the space between the slits need to be about the same as the wavelenght of the light, and thats 650 nanometers. Tell me, how im going to even come close to such a slit? I have tried the with cards and mirrors, but dont even get close.
  6. Jul 8, 2005 #5
    didn't you read the replies?
  7. Jul 8, 2005 #6

    Doc Al

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    Not so. You should be able to easily see a pattern with slit spacing on the order of 0.5 mm. (Put the screen a meter or so away from the slits.) (http://en.wikipedia.org/wiki/Double-slit_experiment#Conditions_for_interference)

    Please look at the link that brewnog supplied. It's easy!
  8. Jul 8, 2005 #7
    Yes, I remember some 5 years ago or so in high school physics we painted microscope slides black and used a rasor blade to cut out two slits, we then held it to our eye and looked at a light source. Such as an incandescant bulb which has a full spectrum. Doing this you are able to observe interference.
  9. Jul 8, 2005 #8
    Its is now done.
    The main problem was the distance between the the screen and the splits.
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