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Thread: X-Ray's

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  1. #1
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    X-Ray's

    How much X-ray radiation come off a 50 watt laser? Anyone know?

  2. #2
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    None that I would think of because you are not operating that far into the spectrum. Visible light is a bit down farther from x-rays. A laser tube is nothing more than a glorified neon sign tube operating in the neighbor hood of 1500 volts. To get x-rays out of a tube you are starting with voltages in the neighborhood of 60,000 volts and up.
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  3. #3
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    Are you sure? My laser is around 25,000 to 30,000 volts, they install metal shield in TV sets because of the radiation they would produce. I was thinking that I should do the same, enclose my laser tube in metal.

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    At those voltages there may be a small amout of rays produced but due to the voltage levels the rays will have a very low energy level and will dissapate very quickly. If it bothers you, you can add a metal shield around the tube.
    If it's not nailed down, it's mine.
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  5. #5
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    Cool that's what I needed to know.

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    What kind of power output of the laser please? I use several 5mW HeNe lasers and have never bothered with shielding at all (for years).
    I love deadlines- I like the whooshing sound they make as they fly by.

  7. #7
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    Quote Originally Posted by ImanCarrot
    What kind of power output of the laser please? I use several 5mW HeNe lasers and have never bothered with shielding at all (for years).

    I'm running a 50w, I don't understand "never bothered with" radiation can and will cause cancer, in most cases you will not know it for "years". That is why I'd like to limit my exposure to nil, NOW. I'm using my laser everyday, so If their is somthing I can do to protect myself then I'm all for it.

  8. #8
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    Also the anode side would be what could radiate the x-ray.

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    Sorry I couldn't finish what I wanted to say, I had to leave right away for an emergency service call. What I wanted to say was that an x-ray tube head operating at 80 KVP @ 8ma. with an 18 second exposure time standing 6' from the front end of the tube head (aimed right at you), it would take over 1350 exposures just to get one of those medical radiation badges just to register.

    You get more radiation from an evening of watching TV or walking out to your car in full sunshine than you would get from a full mouth series at the dentist (15 x-rays) with a tube head operating at 70 KVP @ 7ma.

    As for shielding your tube it doesn't have to be anything fancy, it could be something as simple as aluminum foil wrapped around it or an aluminum tube, it doesn't have to be lead. Be careful as not to get to close to the power leads, you don't want a flash-over (arcing).

    An x-ray tube is a basically a vacuum tube diode. In a vacumm, the electrons are heated (filament) and literally pulled off by high voltage and slammed into an angled plate producing x-rays. A laser tube ionizes a gas with high voltage by causing electrons to be pushed up into higher and higher energy levels. As they fall back down they give off light. This light is reflected back and forth between two mirrors, one being full surfaced and the other half surfaced. Once the light has gained enough energy it passes thru the half surfaced mirror and exits the tube as a beam.

    That is it in a nut shell. Sorry if I rambled on a bit.
    If it's not nailed down, it's mine.
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  10. #10
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    I totaly agree that Nil radiation is perfect- I was Radiological Protection Supervisor for a Large Missile Company. I gave it up when it was decided that we had to comply with ISO14000- the Environmental Standard- making environmentaly friendly missiles just seemed wrong- they are meant to destroy the environent lol- the hypocracy of the arms industry eh
    I love deadlines- I like the whooshing sound they make as they fly by.

  11. #11
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    Thank you this thread has put my mind at ease. Thanks CNCzone!

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