I'm new, but i had a great idea dealing with 445 goggles

[FlashFire]

I agree that nothing here (or anywhere) trumps safety. That said, each persons safety is their own responsibility. Any self-constructed eyewear should be tested on an individual basis to meet or exceed the same parameters that certified glasses do before even considering treating them as anything more than an experiment. It sounds like Ben knows that, and he should, for it is common sense.

I do not, however, believe that anybody should censor their ideas to create their own safety gear, simply because someone else may read it and attempt it with less sense. Call me cold, call me old school, or just call me a jerk -- I don't care, but if someone injures themselves while not working safely, after reading information or ideas posted here or anywhere on the internet, that is 100% their own fault, and I would not feel the slightest bit of responsibility, nor sympathy.

It is not our job to protect idiots from idiots; that task belongs to Darwin. To censor ideas like these threatens the very nature of open innovation that leads to advancement of one's own skill, and occasionally, of science overall.

 

[Tech_Junkie]

No one is trying to censored anything. I clearly said experimenting is good, but only after you have proper protection first. I dont see why this is causing such drama. My 445nm 1.1W laser lights black paper on fire. What do you think it will do to your eyes? Say your testing your home made goggles, and a reflection catches your eye, or burns through the welding lens? Now who is the idiot? I'm all for new ideas, experimenting, modifying, and updating, but not at the cost of someones eyes.

Kids are not idiots, they are inexperienced at what we take for granted, and they are impressionable. As a laser community its our responsibility to lead by example, and to help keep people safe. With all the bad press lasers are getting now, the last thing we need is the headline "Kid burns his eyes wearing his dads scratched welding glasses".

 

[FlashFire]

I thought it had been established that proper protection is necessary first. I don't think anybody disagrees with that. The idiot is anyone who accepts any type of substitute for said proper protection, without thoroughly testing it to prove equal first.

Perhaps kids legally do not have the responsibility, but that still doesn't mean it's ours, for two reasons: 1) The experiments and work described here are riddled with references to safety awareness and links to purchase proper eye protection. It is clear that danger is involved. 2) Nobody is recruiting people to this community, and this thread isn't a "how-to". It's nothing more than an idea. Nothing suggesting anybody else should try any part of it, nor any reward for doing so.

If I buy a service manual so I can replace my own drum brakes, and injure myself because the book failed to warn me of a known danger, there is a clear liability. If I read a forum page where a stranger (untrusted source) describes in detail how he (possible differing situation) did it, there is not. If I try to mimic what he did, and injure myself trying, that's nothing but my own dumb fault for not getting accredited information on how to proceed.

 

[Tech_Junkie]

 

[Morgan]

I thought it had been established that proper protection is necessary first. I don't think anybody disagrees with that. The idiot is anyone who accepts any type of substitute for said proper protection, without thoroughly testing it to prove equal first.

Perhaps kids legally do not have the responsibility, but that still doesn't mean it's ours, for two reasons: 1) The experiments and work described here are riddled with references to safety awareness and links to purchase proper eye protection. It is clear that danger is involved. 2) Nobody is recruiting people to this community, and this thread isn't a "how-to". It's nothing more than an idea. Nothing suggesting anybody else should try any part of it, nor any reward for doing so.

If I buy a service manual so I can replace my own drum brakes, and injure myself because the book failed to warn me of a known danger, there is a clear liability. If I read a forum page where a stranger (untrusted source) describes in detail how he (possible differing situation) did it, there is not. If I try to mimic what he did, and injure myself trying, that's nothing but my own dumb fault for not getting accredited information on how to proceed.

Incidentally, it doesn't seem that anyone who should have has read the links TJ posted back on page one. LSRFAQ, (one of the most knowledgeable members I know of regards all aspects of lasers and can be considered the man that wrote the book!), states several reasons why it's not recommended. Burning, (yes, a non certified material may hold up for a few seconds); bleaching, (protection is reduced each time a strike hits); etc... By all means test for yourself but I still don't think the equipment will do the job or that the results can be gained accurately enough. No LPM is a huge handicap. I see your point, to a point. I like experimenting but, to paraphrase LRSFAQ in one of those links, "... none of these materials have proved adequate under testing...".

@ TJ - Good time put into finding those links, BTW. Spot on!

M

 

[IsaacT]

Try making eyeballs DIY and lemme know how that goes mk?

 

[FlashFire]

That response is valid to the topic, but not valid to my argument, so I'm not sure why it was posted as a reply to me directly. My argument concerns the ethics of discussing methods for improvising your own safety glasses, and of using ones that prove equal to commercially available sets.

More on topic, I have significant doubts that most theater gels would be sufficient and pass the required testing. That doesn't mean he shouldn't try, though!

 

[Morgan]

That response is valid to the topic, but not valid to my argument, so I'm not sure why it was posted as a reply to me directly. My argument concerns the ethics of discussing methods for improvising your own safety glasses, and of using ones that prove equal to commercially available sets.

More on topic, I have significant doubts that most theater gels would be sufficient and pass the required testing. That doesn't mean he shouldn't try, though!

The point here is that NO HOMEMADE GOGGLES WILL PROVE EQUAL. That is it. When I build a DIY laser, it is close to a gaurantee it is better than a commercially available one for the same money, (and in a lot of cases better than ones much more expensive). Homemade goggles, however, will never be as good, or better. Being on one side of this line for the lasers is one thing. Being the other for the goggles is quite another.

Did I say he shouldn't try testing some? No, I don't think I did, but for definitive testing the member needs more equipment, the tests would have to be specific and take quite some time.

This has been covered now I think. I'll be interested to see some definitive results but I fear we won't get any useful science from this so I will be sticking to my pre-thread position of, "Don't try this at home". No offense.

M

 

[LazyBeam]

If you like, send me any gels/filters you want tested And I can run them through a spectrophotometer I have access to @ work. This will give you a transmittance/absorbency plot and the corresponding OD plot for all wavelengths (UV, visible, and IR). If you like, it will even distinguish whether a wavelength is reflected or absorbed. The machine we have is sensitive enough to detect up to about OD4 for what it's worth.

I'll do it free (IMO it's fun so it's not really "work") and it's completely nondestructive so you can get the gels/filters back if you want to pay return postage. More importantly, this is testing that is 100% operator safe, quantitative, and puts NOBODY at risk by testing with high power lasers.

Here's a transmittance scan of the WL Lasershields that I made just to show you what I'm talking about.
http://i53.photobucket.com/albums/g45/jrm33/2704cac8.jpg

 

[Morgan]

^ With respect LazyBeam, it needs more data than that. Yes that will give specifics for transmittance etc but the test does need to be destructive. It's not just about the wavelength.

It'd be good to do these tests, however, to measure how close they come to manufacturers declared specs so it may be a useful exercise. Just still not definitive.

M

 

[LazyBeam]

Yes you are correct - of course you would need to test the filter robustness. Goggles need tested for transmittance and stability to obtain certification.

However, that can be tested easily by using an LPM and shining a collimated beam through the filter. If the LPM holds steady then the filter is OK for that power. If it gets burned or degrades then it will be evident either more layers are needed to lengthen the protection time or the material can be compromised too easily.

There are probably 2 dozen people on these boards that can test power transmission stability. In fact, I do plan on building an LPM so I can test that as well. But I figured that, being lucky enough to have access to a spectrophotmeter, I could offer to see what the filters actually protect against.

 

[DrSid]

With focused 1W laser, any plastic goggles would be burned through under 1 second. The power must go somewhere. Except if they would reflect the beam, but that is not considered good too. On the other hand, direct focused hit is pretty hard to achieve .. it's reflections you have to fear. They are practically never focused, and practically never 100% of the power.
So IMHO it's no problem that the goggles can be burned through. If they can be burned through, it means they absorb the radiation well.
I also think it's not big problem if the goggles reflect the beam. Anybody in the room with class IV laser should wear glasses too, and we are talking about rare situation when you unfortunately take a reflection in the glasses. I can't see how reflection can be bad.
If the glasses would bleach with diffuse reflection, or simply with time, now that would be a problem.

 

[Coherent Light]

It would be great if L_B can test Some common filter Media, and I think plenty of Us Would appreciate His effort. My take on this issue is this. Anyone can at His or Her choice decide to construct laser safety eye wear with the knowledge they are taking a risk. Now if They then post their results in an open forum someone will eventually take the results to heart and construct for themselves a SIMILAR but not necessarily equal pair ASSUMING because someone else did it that they are SAFE. Most of US here know full well that following someone else step by step is not a guarantee of the same results. The person who posted the instructions and out come is in no way responsible for some dumb ass who damages their vision because they tried to copy said results, but why tempt fate and even suggest that home made safety eye wear is in anyway safe to use.

My $0.02 worth.

 

[Bluefan]

With focused 1W laser, any plastic goggles would be burned through under 1 second.

A solution:

Laservision laminated glass filter goggles, my favorite.

We're hobbyist, if one of our lasers breaks down, we're unhappy but that's it. In professional situations, it's a big problem, so they use expensive stuff that lasts. For laser safety it's different, if our goggles break down by a hit, we lose the same eyes as a professional would lose. That's why we prefer to have the same safety eyewear as in professional situation.

I understand that people want cheap eye protection, I started out the same way. For low power lasers I can see this work out not too bad, a direct hit won't put much stress on the goggles (test this out!). you'd still have to test for the right OD, but it's possible. For higher powers, you'd need to test for the strength of the goggles in practically all situations possible and other come into play too.

Laser safety goggles that are EN207 certified have not only been stress tested to see if both filter and frame keep their rating for 10 seconds of 100 pulses of a direct hit, but also for (from the booklet that came with the goggles):
- no Q-switch effect
- Low dioptrical effect
- quality of material and surface
- low stray light
- no secondary radiation
- UV resistance
- thermal resistance
- field of vision >40deg
- shatter resistance

This is why I use the real stuff. I now don't have to worry about my safety because I know it's right. Making goggles yourself that fulfill these kind of strict requirement is definately very hard.

You can lose your vision by 10mW or 1000mW, your screwed either way. that's why I recommend to buy real laser safety goggles even for low power lasers, just to be sure.

 

[IsaacT]

VERY well put, +1

Just looked on laservision, and after some searching I do believe I need to now save up 279 dollars

 

[Bluefan]

On a financially lighter note: there are plenty EN207 certified plastic based goggles. Plastic can take a drop to the floor better, but even though real laser eyewear is made of robust plastic, a good laminated glass filter can take more light.

But I the reason I have them is that just love the laservision protector frame style. With the usual goggles, the arms press around my ears, it presses on my nose, light can leak around the glasses and they can fall of when you bent over.
With the protector frame, there's practically 0% chance of light passing around the goggles, a thick band around your head that sits comfortable and keeps the goggles on even when I'm upside down without any pressure points on my head.

And the sturdy frame is the limit, the steel reinforced frame version is rated even higher. I have these also with a filter for IR, I really love these.