Short indirect exposure to 1.6W laser reflection without goggles

How likely are you to sustain even a mild eye damage through brief exposure to a 1.6W laser scatter of a material such as basswood? I’ve accidentally stumbled into my office without the protective glasses thinking the laser had already completed the job, except it hadn’t. I’ve been engraving basswood and could clearly see the blue reflected laser light however only briefly. In reality how dangerous is this to the eyes? I’m asking because I don’t have a lock on my door and worry about another family member accidentally doing the same. That said I’ve explained the safety protocol to everyone already. I’ve been Googling and cannot find a definitive answer.

Thanks everyone.

I suspect you’d have noticed by now if you had damaged yourself this time. For the future, consider putting something opaque over the unit when you’re doing laser work with it. Even just a cardboard box or a blanket or old curtain thrown over the enclosure would vastly increase your safety. (I went a bit further and retrofitted the front of my enclosure with an OD3+ panel, but that’s more pricey.)

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You might consider a setting up a pi with octoprint and camera. I can monitor the laser progress from a computer or device. But as word of caution, I would never leave a laser running unattended, you never know what could happen.

I am not an expert, but honestly I would not worry too much here. The reflection of the beam is diffuse, i.e.the laser light is scattered in all directions. The 1.6 W, distributed on a half-sphere, will rapidly drop down to safe intensities with distance. Also, the wood absorbs considerable amounts of the laser - thats the reason it gets burnt/cut.

Things become a different story with direct reflections of the beam, e.g. on a screw in the laser platform or so. A direct beam hit will damage the eye in fractions of a second, too fast for the eye lid to react and close. So I’d recommend that you follow the advice of the other people answering above and create a protective environment - especially if your beloved ones might accidentily walk in.

A lock is cheap if used before the accident happens.

Scatter radiation, especially at the level of the 1.6W is generally “safe” in brief glimpses. Please do not take my use of the word safe out of context, it’s not harmless, just should not cause lasting damage. You may get eye stress or maybe those temporary ‘burn’ spots you see when viewing bright lights, but scatter radiation is a lot less energy than the focused point. As @Hauke mentioned, the wood is absorbing most of the energy, but if you were to do anything reflective, or non-organic, the scatter radiation would be a bit higher and hurt more. However, with the length of the shroud on the 1.6, risk is minimal for accidental viewing damage. If you were using the 10W, stricter safety protocols would definitely be advisable. It sits considerably higher above the object being burned, and is a lot stronger in terms of power.

Maybe make a shelf right beside the door handle for the goggles to sit on (and easily visible to anyone walking to the door) with a sign to ALWAYS put them on before entering. It’s not foolproof by any means, but it’s a good reminder to prevent stumbling into the room while still going.

EDIT: Or put some of those glasses straps on them and hang them on the door knob itself, while affixing a sign to the door.

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Yeah I think it’s time to set up octoprint. Shame we can’t use the integrated camera in the laser module to monitor the job in real time.

Of course, however I have a double french door that just pops open even if closed. I’d need to replace or modify the door to install a lock.

Thank you that’s what I was hoping to hear. I’ve actually removed the laser module right after my little walk-in and keep it that way until I can child-proof my setup.

I just realised there’s literally a sound-proofing panel behind the machine I can just move it and jam it between the two desks. Thank you for such a simple but effective idea!

No to mention Octoprint is a lot more useful with 3D printing as well.

But no enclosure? Or exhaust fan? I’d be investing in those as well, ASAP. I installed a more powerful exhaust blower as well. Best $20 investment ever. The stock one is pretty poor. It’s basically a PC power supply fan.

One of the reasons lasers are so dangerous is because your brain lies to you. You can suffer damage that burns out rods and cones, and your brain will just fill in the missing information. It’s the same way your brain manages its blind spot.

Because of this, you can suffer a significant amount of damage before you notice it. It’s impossible for you to tell at this point if the damage was temporary or permanent. By the time you’ve suffered enough damage that you can tell, you’re effectively blind in that eye.

If you have any concerns, you should see an Optometrist. They can take pictures of your eyeball and tell you if the damage is permanent. Since you’ve solved the problem, I wouldn’t make a special appointment. I’d mention it at your next scheduled appointment.