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A tiny ultrabright laser that can melt steel

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Re: A tiny ultrabright laser that can melt steel

#42
post #7

A society in which "the average car-buyer" has a tiny portable steel-melting laser is a society where I'm wearing welding goggles every time I leave the house. And I'm not sure how you even lock a bike or a door or a safe any more.

"The average car-buyer or metalworker" can already afford a $30 cordless angle grinder:

https://www.harborfreight.com/power-tools/grinders/angle-gri...

(Cost plus a $30-$80 battery, of course, but after you pick your color, you've already got batteries). Your locks are far more protected by the social contract that would compel a stranger to stop someone who was cutting a bike lock with an angle grinder, and would cause a thief to fear arrest, prosecution, and jail time, than by actual physical security.

If you want a laser, you can already get a 100W CO2 laser tube for $500:

https://www.amazon.com/Cloudray-W2-Dia-80mm-Engraver/dp/B08G...

It won't do a great job of cutting steel - it will engrave it, but to cut steel you'd need O2 assist gas and a lot more power. It will trivially cut ABS, foam, fabric, wood veneer/thin plywood, cardstock, etc. if attached to a pair of mirrors on an XY stage such as might be borrowed/scaled up from a 3D printer. And, of course, it will trivially scar corneas with the invisible danger of its 10,600 nm laser light. Good news, though - ordinary polycarbonate safety glasses are opaque to the extreme IR light.

Laser safety is serious business, but highly-collimated, tightly-focused laser light is not likely to be produced by a cheap, portable laser. The above tube produces a 100W beam with a diameter of about 8mm. I wouldn't put my eyeball in the path, but a safety shutter can sit in the beam indefinitely and merely get warm. You melt steel by focusing a this 8mm beam down to a infinitesimally tiny spot, and beyond the focal length of your optics it diffuses to something no more dangerous than the source 8mm beam, and beyond that it's no more dangerous than an average lightbulb - albeit one that you have no aversion response/blink reflex to. I always wear my goggles near our cutting lasers, but I know lots of guys who have worked around 20W-20,000W CO2 lasers their entire lives and they're pretty cavalier with regards to laser safety.

Finally, a welding mask is a neutral-density filter, suitable for the (very approximately) black-body radiation produced by a welder, and is much less effective than laser safety goggles at blocking high-intensity light of a very specific color. Depending on the sensor, an auto-darkening mask might not even trigger when exposed to a laser! You'd want a set of 940nm laser safety goggles for this, which is far more exotic and dangerous than a 10um CO2 laser.

Re: A tiny ultrabright laser that can melt steel

#43

Can you use this for 3d printin? Like in an array of lasers where every laser is a pixel and you get 3d by shifting a powder layer. Could this architecture be faster then current 3d printers?

Yes, there are such printers in existence already --- they either use a laser to melt a layer of metal powder, or spray a binding agent on a layer of plastic powder --- for the latter it's possible to include a colouring agent and get full-colour 3D plastic prints.

Search term is "Laser powder bed fusion" (as opposed to the trademark: "Direct Metal Laser Sintering" as was pointed out below)

https://www.3dsourced.com/guides/direct-metal-laser-sinterin...

Re: A tiny ultrabright laser that can melt steel

#45

Earlier quoted context omitted.

A dutch women told me once a story, where she but a used bike in Amsterdam and the heroin addict who sold it to her, threaten her to steal it again, if she does not use a heavy lock.

When I moved to the Netherlands my boss told me to never spend more than 20 euro on a bike because it will get stolen. I didn't listen, and lo and behold two weeks in my 75 euro bike and the 35 euro heavy duty lock disappeared

That is rather sad to hear.

Re: A tiny ultrabright laser that can melt steel

#46
I wonder if the surface emitting nature of these will make it easier to phase lock multiple chips. This could be very useful for large apertures and power beaming over long distances.

One application for high efficiency large aperture lasers is powering long distance aircraft, either by beaming from ground stations along the way or from laser stations in space. The ability to forego fuel entirely would be quite attractive, allowing potentially unlimited range.

Re: A tiny ultrabright laser that can melt steel

#47
post #39
post #28

Earlier quoted context omitted.

Those can’t blind you from a distance though. Not nearly the same risk

They absolutely can. Anyone around them for long enough has dead spots in their eyes.

I mean like a bystander walking by a construction site who just happens to catch a bad reflection for a fraction of a second

Re: A tiny ultrabright laser that can melt steel

#48

Earlier quoted context omitted.

A dutch women told me once a story, where she but a used bike in Amsterdam and the heroin addict who sold it to her, threaten her to steal it again, if she does not use a heavy lock.

When I moved to the Netherlands my boss told me to never spend more than 20 euro on a bike because it will get stolen. I didn't listen, and lo and behold two weeks in my 75 euro bike and the 35 euro heavy duty lock disappeared

I'm skeptical:

* Where do you buy a ≤20 euro bike?

* Most people on the street have bikes that look to be at least 200 euros new, from what I can tell.

Re: A tiny ultrabright laser that can melt steel

#49
post #46

I wonder if the surface emitting nature of these will make it easier to phase lock multiple chips. This could be very useful for large apertures and power beaming over long distances. One application for high efficiency large aperture lasers is powering long distance aircraft, either by beaming from ground stations along the way or from laser stations in space. The ability to forego fuel entirely would be quite attra…

>> make it easier to phase lock multiple chips

Another use for that is holography. If you can make a wafer-scale array of phase locked emitters overlayed with the ability to either attenuate or phase-shift each one, it becomes a nice (one color) holographic display. I'm assuming high divergence from each one.

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