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A tiny ultrabright laser that can melt steel

spectrum.ieee.org

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Re: A tiny ultrabright laser that can melt steel

#161

Post by dtgriscom »

sarchertech wrote: post #17
aqme28 wrote: 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.

There are already so many ways to defeat locks, that locks are just there to keep honest people honest and to slow down criminals. The laser in the article took 30 seconds to cut a a tiny disc out of a sheet of steel 100 micrometers thick. That isn’t going to change things on the theft front. There are much more effective methods available today.

> 100 micrometers thick

1/10 of a millimeter. Thick foil (perhaps 4x generic Al foil).

Re: A tiny ultrabright laser that can melt steel

#162

Post by dtgriscom »

sarchertech wrote: post #17
aqme28 wrote: 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.

There are already so many ways to defeat locks, that locks are just there to keep honest people honest and to slow down criminals. The laser in the article took 30 seconds to cut a a tiny disc out of a sheet of steel 100 micrometers thick. That isn’t going to change things on the theft front. There are much more effective methods available today.

I divide locking systems into three classes:

1. Can be opened without tools

2. Can be opened with generic tools (e.g. hammer, hacksaw)

3. Can be opened with specialized tools (e.g. lock picks, liquid nitrogen)

Re: A tiny ultrabright laser that can melt steel

#163

Post by w10-1 »

This reminds me of the latest ASML machines coordinating UV laser (angle) and diffraction grating to achieve clean small 2D patterns.

I'm curious how hard it is to model light interactions on this scale. What does it take for the authors to come up with modeling solutions for their scaling problems? Is this something one PhD in light physics could do, or do companies and people develop expertise in teams over decades?

It seems like ASML only requires the solution to one wave diffraction interaction (with the mask), but modeling the standing wave and higher-order modes would require much more mathematics. Is it even possible if the solutions for each interaction are probabilistic?

Also, are solutions in practice mostly bounded by the kinds of semiconductor features (holes) they can build?

Re: A tiny ultrabright laser that can melt steel

#165

Post by swader999 »

notyoutube wrote: post #48
passwordoops wrote: post #25

Earlier quoted context omitted.

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.

Police unclaimed bike auctions maybe.

Re: A tiny ultrabright laser that can melt steel

#166

Post by drtgh »

ChrisMarshallNY wrote: post #159
IshKebab wrote: post #156

Earlier quoted context omitted.

A 5W laser can't cut steel. You need to be in the kilowatts before you can cut metal (unless it is very very very thin).

You may well be correct, and I spoke out of turn, but it is my understanding that the wavelength of the laser can make a huge difference.

I'm sorry, but there's no way around it, with 5W you can cut metal just as easily as you can cut a tree with a knife. At least with contemporary technology (In the future who knows).

Re: A tiny ultrabright laser that can melt steel

#167

Post by ordu »

aqme28 wrote: 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.

> 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.

VR-headset will be better, because it can attune brightness and contrast so you can see even at dusk.

Re: A tiny ultrabright laser that can melt steel

#169

Post by bsder »

coder543 wrote: post #67
83 wrote: post #60

Earlier quoted context omitted.

The precision of a laser cutter would open up a lot of possibilities. Particularly making things that slot together with tabs - like fabbing my own welding squares and fixtures where a cnc plasma cutter would leave too rough an edge to have them slot together accurately.

Can't you buy a CNC mill/router that can cut metal more precisely than a CNC plasma cutter?

Tormach metal CNCs are $10K+ and take up a lot of floorspace.

A lot of people also cut sheet metal which a CNC tends to be terrible at.

Re: A tiny ultrabright laser that can melt steel

#170

Post by coder543 »

bsder wrote: post #169
coder543 wrote: post #67

Earlier quoted context omitted.

Can't you buy a CNC mill/router that can cut metal more precisely than a CNC plasma cutter?

Tormach metal CNCs are $10K+ and take up a lot of floorspace. A lot of people also cut sheet metal which a CNC tends to be terrible at.

We're talking hobbyist grade stuff here. People mount router bits on $400 CNCs and cut metal all the time.

Not $10k: https://youtu.be/w26DHMccicE?t=637

Even though it's cheap, the cuts still look pretty smooth and precise. I can't speak to the safety, as I would hope a $10k CNC would have more safety features.

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