0
$\begingroup$

I am working on a CO$_2$ laser project and I know glass blocks the wavelength of the laser, 10,600 nm, well. So, should normal glasses work good as safety glasses or do I need to buy a specific one?

PS: Am making a simple CO2 gas Laser by studying from online resources for my major project, and it won't be very high power.

$\endgroup$
  • 2
    $\begingroup$ Get some real laser safety goggles. (a ~$200.) You don't want to loose an eye. (buy a few pairs.) about 1mW into your eye is enough to damage it. $\endgroup$ – George Herold Oct 20 '14 at 14:37
10
$\begingroup$

When working with any laser above class 1, you should seek appropriate qualification for dealing with your specific laser system (which includes both its wavelength and its power), and you should inquire with your institution as to any formal safety requirements.

Specifically, you should not take laser safety advice from what are essentially random strangers on the internet, and certainly not without verifying it externally with a qualified professional.

A good place to start looking for information is the manual of your laser system, which must include a safety section which sets out clearly what is and is not appropriate protection equipment. Laser goggles will correspondingly have specifications which you need to match carefully to what your laser system requires. Do not, however, assume that normal glasses will work appropriately as laser protection, without checking with a qualified professional.


For a home-built system, you obviously need to proceed with extreme caution. Unless you are completely, absolutely sure that you will never have more than 1mW power in the beam (hint: you're never sure), you cannot dispense with safety equipment.

One thing you should be particularly aware of is that in the infrared, your blink reflex won't protect you. This means that there is no such thing as a Class 2 infrared laser, and you should therefore assume, at the very least, that your laser is Class 3.

I should stress, again, that it is nothing but reckless to take safety advice off strangers from the internet. Similarly, if the online resources you are using to build your lasers don't have a clear section on laser safety, I would advise you to stay well away from them.

$\endgroup$
0
$\begingroup$

There is nothing wrong with working in a completely enclosed box which has an electric safety switch that turns the power off as soon as it is opened. That is exactly how a professional engineer/physicist will solve this safety problem: with deadlocks like this and measures that prevent the beam intersecting your eye under all circumstances of "normal" use. You don't have to "see" how an invisible beam is being generated in front of your "eyes". There is nothing to see, to begin with.

$\endgroup$
  • 2
    $\begingroup$ If you're building the laser yourself, you're likely to need to defeat the interlocks to work on the laser to get it working. $\endgroup$ – The Photon Oct 20 '14 at 20:50
  • $\begingroup$ @Photon: The function of an interlock is not to prevent people from being stupid by willfully bypassing it. It's there to protect humans from being human. We are all forgetful about danger if nothing bad happened to us the first hundred times. There are, of course, safe ways to e.g. adjust resonator mirrors on a laser without ever getting into the beam path. Professionals extend a great amount of energy on doing things the safe way. There is no reason why an amateur couldn't. After all, one can only win the Darwin Awards once and thinking about ways of not entering the contest makes us better. $\endgroup$ – CuriousOne Oct 20 '14 at 23:54
  • 1
    $\begingroup$ My point was, having the laser in a locked box doesn't save you from having to buy a decent set of safety glasses. Which probably isn't what you were trying to say but it is how I read your post the first time through. $\endgroup$ – The Photon Oct 21 '14 at 0:49
  • $\begingroup$ @Photon: Nowhere did I say that a professional won't be using multiple methods of protection at once. Safety glasses alone, however, are simply not considered sufficient in today's environment, especially not if one has to deal with high voltage and a coherent optical source at once. $\endgroup$ – CuriousOne Oct 21 '14 at 0:57
  • $\begingroup$ did you miss the part where I said, "Which probably isn't what you were trying to say but it is how I read your post the first time through."? $\endgroup$ – The Photon Oct 21 '14 at 0:58

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.