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Laser Products I Hate

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Re: Laser Products I Hate

#41

Post by rjzzleep »

analog31 wrote: post #15
rjzzleep wrote: post #9

On that note, does anyone have good resources on building laser powered products? I figured it would make sense to start by reading an optics textbook. [1] Something like Building Electro-Optical Systems by Hobbs. First problem is that I wouldn't even know which ones good. The next problem I see and which the article touches on is that the wrong setting might cause irreparable tissue damage. Which by extension means…

I have Hobbs, and it's a great general book. But it may fall into that fine literary genre of "explanations for people who already understand things." Hobbs assumes a fairly advanced understanding of physics and electronics. You might be able to learn how to make gadgets that work at the prototype level, but designing a potentially dangerous product is engineering. I don't know how you do that without working as an e…

Which regulations do you have to follow / which standards do you have to adhere to when it comes to proving reliability of the developed laser product?

Also if Hobbs is a great general book, what would be an example for something more specific? I'm particularly interested in near-infrared lasers.

Re: Laser Products I Hate

#42

Post by fest »

analog31 wrote: post #15
rjzzleep wrote: post #9

On that note, does anyone have good resources on building laser powered products? I figured it would make sense to start by reading an optics textbook. [1] Something like Building Electro-Optical Systems by Hobbs. First problem is that I wouldn't even know which ones good. The next problem I see and which the article touches on is that the wrong setting might cause irreparable tissue damage. Which by extension means…

I have Hobbs, and it's a great general book. But it may fall into that fine literary genre of "explanations for people who already understand things." Hobbs assumes a fairly advanced understanding of physics and electronics. You might be able to learn how to make gadgets that work at the prototype level, but designing a potentially dangerous product is engineering. I don't know how you do that without working as an e…

On a related note- do you know of any books that cover diode laser safety? Specifically, I'm working on a FMCW laser rangefinder (hobby project to teach myself more of analog electronics) and would like to know what is the maximum optical power I should use.

Re: Laser Products I Hate

#43

Post by [deleted] »

arkades wrote: post #28
microcolonel wrote: post #24

Earlier quoted context omitted.

Yeah, I don't really see the issue. People play with knives, operate firearms, use table saws, and cross the street in traffic all the time. The stakes are high in life, and if you're not careful you might poke an eye out with that thing, but what fun is a world where everything is engineered to be too dull to poke an eye out?

Because the selling point is public use: its not just dangerous for the operator, but goes out of its way to invite bystanders.

[deleted]

Re: Laser Products I Hate

#44

Post by jschwartzi »

rjzzleep wrote: post #41
analog31 wrote: post #15

Earlier quoted context omitted.

I have Hobbs, and it's a great general book. But it may fall into that fine literary genre of "explanations for people who already understand things." Hobbs assumes a fairly advanced understanding of physics and electronics. You might be able to learn how to make gadgets that work at the prototype level, but designing a potentially dangerous product is engineering. I don't know how you do that without working as an e…

Which regulations do you have to follow / which standards do you have to adhere to when it comes to proving reliability of the developed laser product? Also if Hobbs is a great general book, what would be an example for something more specific? I'm particularly interested in near-infrared lasers.

In the US, lasers are FDA-regulated. This is true even if they're not used for medical purposes.

Re: Laser Products I Hate

#45

Post by jerf »

microcolonel wrote: post #39
pdkl95 wrote: post #36

Earlier quoted context omitted.

> Stray reflections can easily blind. To emphasize this point, since we're talking about a 450nm laser at either 500mW (maybe just barely low enough to hypothetically qualify as Class 3B?) or 800mW (probably Class 4?), any stray reflections could easily cause blindness before the eye can respond by blinking . Any laser powerful enough to burn or cut is a "why did my eye make a popping sound"[1], risk, not the " blink…

Here's a video of a public axe throwing contest with amateur participants, no backstop, and people directly behind it. https://youtu.be/EeiMvKuXs0E People endanger the public at large all the time, knowingly or unknowingly. There is no decent world in which acts which merely pose a danger to the public are illegal before they cause that danger.

People instinctively understand the risks of throwing things, even sharp and heavy things. People do not have an instinctive understanding of the risks of lasers. They may both be dangerous, but that does not mean the two levels of danger are the same.

Re: Laser Products I Hate

#46

Post by VLM »

Consumer lasers will be the spray paint of the next century. One small segment of the population will see them as an overly expensive way to accomplish tasks slightly more conveniently than the alternatives, and another larger segment of the population will use them mostly to trash their environment, leading to all kinds of weird attempts at legal restrictions.

No one has mentioned the obvious terrorism related issues with lasers. The worst body counts won't be individual random "makers" with poor coding skills and their bystanders, or even the cops, it'll likely be, say, an entire stadium instantly blinded, or really any public location, such as interstate highway overpasses or airport security lines. I suspect we'll soon have discussion on the topic of "weapons of mass destruction" as applies to lasers. Based on past experience, if some Saudi citizens snuck something in to the stadium (drone delivered?) then blinded everyone attending the Superbowl, would we invade Venezuela conventionally or nuke Iran?

Re: Laser Products I Hate

#47

Post by wnkrshm »

I work with lasers and we get a yearly security training on staying safe with lasers (the whole shebang, videos of cow-eyes exploding from diffuse scattering of a cutting laser, cutting pizza, photos of scars of accidents, post-trauma photos of retinas etc).

It is indeed terrifying to see how easily you can get tools that can cripple people without people being aware of the danger.

Re: Laser Products I Hate

#48

Post by wnkrshm »

jdietrich wrote: post #34
stavros wrote: post #19

Earlier quoted context omitted.

Why are you comparing a weapon that has to hit a whole person and misses to a weapon that has to hit a 5mm retina and somehow never misses?

It's not difficult to track eyes consistently using computer vision. It's not difficult to aim a laser beam using a mirror galvanometer. If you're struck in the eye with a UV laser beam, the blink reflex doesn't kick in - by the time you've noticed the pain in your eyes, it's already too late. The beam doesn't have to track with particularly high accuracy to cause certain blindness, especially if there's an array of…

A UV-laser would be humane, since UV (and shorter wavelengths) will interact with the outermost portion of your eye - visible light or the near IR (up to 1500) is what your imaging system operates on and it's focused onto the retina.

Edit: Also, the blink reflex isn't fast enough to save you from damage if the Class is higher than Class 2 (and even then it's a roll of the dice, since there are some who don't have that fabled reflex).

Re: Laser Products I Hate

#49

Post by wnkrshm »

anfractuosity wrote: post #6
damnfine wrote: post #2

Interesting that he compares them to firearms, and all that entails. With power levels increasing, we may see a viable laser rifle soon, and with it, a need for a new regulatory structure (or adoption and expansion of an existing one, atf, etc.) They seem to have many of the same public safety aspects, but will someone popularize a legitimate 'Sporting Use' for these devices before they are sold as 'Death Rays to Bli…

I wonder how practical a portable laser gun would be, as I'm imagining a laser diode array would need to be amazingly powerful (I'm assuming much greater than the 40W version in the video?) and they'd require a very beefy power source. It seems diode lasers are up to 60% efficient? It looks like you can get extremely high power pulsed laser arrays though.

It's been researched in the 80s/90s. The best solution was a gas-dynamic laser with a Po-220 (the activity of U238 within its entire 10k years halflife packed into a time of two weeks) reservoir as a heat source.

Re: Laser Products I Hate

#50

Post by anfractuosity »

wnkrshm wrote: post #49
anfractuosity wrote: post #6

Earlier quoted context omitted.

I wonder how practical a portable laser gun would be, as I'm imagining a laser diode array would need to be amazingly powerful (I'm assuming much greater than the 40W version in the video?) and they'd require a very beefy power source. It seems diode lasers are up to 60% efficient? It looks like you can get extremely high power pulsed laser arrays though.

It's been researched in the 80s/90s. The best solution was a gas-dynamic laser with a Po-220 (the activity of U238 within its entire 10k years halflife packed into a time of two weeks) reservoir as a heat source.

Very interesting, I'd never heard of a gas dynamic laser before.

Edit: Is it the Stavatti device you're referring to? Apparently there are some claims that it was a hoax.

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