Safety window for 1064nm & 455nm

LightBurn Hardware Compatibility
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Hi all

Spent a bit of time yesterday looking at options for safety screen for IR1064(OD2) & Blue 455nm(OD6) screens to put on enclosue.

I couldnt find one that does both freq so figured a slide in frame would have to do as fitting both together may make the window too opaque for use.

Just a small window 100x200mm for checking all’s ok in there.

The supplier was from Germany and the catalogue was ok but just a wee bit new and confusing for me, so thought I’d check with you all.

Is there a full spectrum option?

Would perspex full colored (red etc) provide full protection with or without glasses if used for the bulk area of enclosure incase someone entered the area unexpected…if so, Cast or…forgot the other one!

Do I need glasses/eyeware for both modules and are glass glasses better than plastic from a user-friendly point of view.

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Hi.

Nothing wrong with it if You definitely need a window, but IMO in 99% of the cases, a camera will do just fine.
Especially with dual wavelength use (I have the same combo).
Often for a fraction of the price as well :slight_smile: .

I stopped looking for even a single wavelength window pretty quickly when I made my ATA style case for my xTool D1 Pro, so I can’t give You a definitive answer, but I doubt that such a safety window exists.
At least not in the “reasonable price” range.

If You mean solid colour, yes it will.
If it’s at all transparent, then the answer is maybe for without the glasses, yes with the glasses.
The forming method doesn’t matter.

It’s easy to rough-test any plastic sheet by lasering through it.
If a paper under the sheet shows any signs of charring, a significant portion of the energy gets through the plastic.
And if the sheet can be cut/melted with a laser, it can provide at least a partial protection against that particular wavelength.
That’s the reason why the CO2 folks can use about any acrylic glasses/goggles, and us diode operators need expensive glasses/goggles.

You do.

Both have the ability to severely damage Your eyes, even though the damage will be different and for different reasons with the different wavelengths.
In the end the reasons don’t matter much though, if the worst come to worst, You’ll be at least partially blind in a way that can’t be repaired with todays knowledge.

All the laser safety glasses with glass lenses I have seen have been in the price range that at least I can’t justify spending, so I’d say that the options are:

Cheaper (~<100€/$/£) questionable quality plastic ones that may or may not offer protection.

Moderately priced (~100~500€/$/£) plastic ones from reputable brands.

Expensive (>500€/$/£) professional plastic ones.

Like I said, I always use an enclosure and a camera, so there’s been no need to buy or to research deeper any expensive glasses or safety windows.

Regards,
Sam

:finland:

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Excellent Sam.
Thanks for the breakdown, and I think you’r right about the camera.
I managed to get my search terms dialled in a bit better and found a 100x200mm screens around 50euro each, and at ‘thor labs’ eyeware for 160+/-euro per pair.
So I dont know much about cameras but its worth taking a look.

Actually, sounds much safer to see work progress on screen.

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As @LSS pointed out, clear blocks the CO2 light, and transparent red will do a good job blocking the UV (diode) light. Just layer them and you should be okay. Disclaimer: I am not physics, engineering, or doctorial person, so do so at your own risk.

I used red on both of my enclosures. I managed to cut this material with a 10w laser at nearly perfect focus using air assist and multiple passes. The chances of reflected light being at focus when it hit the view window would be super slim. I have both a 10w and 40w diode and just make sure the box is closed before hitting the start button.

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Hi.

You’re welcome.
I don’t like to spend money unless I absolutely need (/want :wink: ) to, so a camera has been perfect for me.
On an unrelated note, a camera+monitor approach is a real time- , money- and labour saver in soundproofed & -treated recording studio environment as well.

Thor labs is a trusted vendor with published OD charts.
Even though the frames do cost something, the bulk of the price is in the lenses, so the price/area difference between the 100x200 sheet and the glasses is rather telling.
In any case, the safety sheet should be purchased from a reputable vendor that publishes the OD charts as well.
Reputable is the keyword here, a questionable lens/sheet at an inflated price is still a questionable purchase.

From the Thor Labs charts:

it’s easy to see that the tint of the lens doesn’t necessarily tell much about the blocked wavelength(s) nor about the OD ratings, so just because a certain plastic sheet -or in the worst case scenario just its coating- has a particular tint, does not mean that it’s automatically safe to be used as a laser safety screen/lens.

Even though it’s not directly mentioned, those graphs and OD percentages in them also show what wavelengths You do see, and that is often the reason why seemingly similar glasses/goggles differ radically in price.
It’s relatively easy and cheap to block all wavelengths more or less evenly, and both the difficulties and the price increase rapidly when a precise cuts are made while other wavelengths are left unaffected.
Since we hobby laser operators generally don’t need to see every minute detail, we can make do wit broader cuts and with less visibility.

It is.
And the same feed can be directed to several locations -even over the web- if so desired.
Even though monitoring with a camera also offers the possibility to remotely operate the laser, that’s generally not recommended, and for very good safety reasons.

The general lighting inside the enclosure, the optics and filtering does play a role in the amount that the camera is able to show though.
The huge energy spike in a narrow wavelength band will overload any camera cell to a degree, so additional filtering may be necessary if finer detais are required.
I haven’t tested them because a general idea what’s happening in there has been enough for me, but photography filters or even stage lighting gels may be used as an additional filtering.
Or digital filtering if the camera/software offers those features.

Regards,
Sam

:finland:

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I bought some of these for my laser enclosure 250nm to 520nm Laser Shielding | J Tech Photonics, Inc.

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Thank’s Samuli, Mike & Jeremy

Lots to ponder over the next couple of days. I think I’ll get the frame together, along with control box, Air assist, cables and tubes and get a layout planned with the thing right there in front of me.

I have a perspex guy up the country who can help with panels and turns out they are associated with a ducting/industrial ventilation company so we can discuss the airflow, ducts and flexi bends that I can get from a company in England.

Was looking at my tools I used to buld my roof a while back and I’m thinking I might call to see a joiner!

Great point’s Samuli on the sheet material cost v lenses! v camera.

Thank’s all

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