Laser Products I Hate(funraniumlabs.com) |
Laser Products I Hate(funraniumlabs.com) |
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?
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 that making sure that the variance is power must have a bunch of failsafe circuitry more so than the average meditation eeg startup.
I believe there are reliability test scenarios for electrical equipment in space, so i assume there's similar things for this use case. Would anyone be able to point in the right direction?
[1]: http://eu.wiley.com/WileyCDA/WileyTitle/productCd-0470402296...
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 engineer for a long time.
Disclosure: I'm a scientist who works in laser product development, among other things, but not a licensed engineer.
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.
It is indeed terrifying to see how easily you can get tools that can cripple people without people being aware of the danger.
Even worse, the EU norm for lasers has been amended for incoherent sources. Previously, LEDs had to fulfill certain maximal radiance requirements to not need a laser sticker. They raised the radiance limit for LEDs by a factor of 100 (so if it was coherent it's about a Class 3 now). I treat bright LEDs/flashlights like lasers now at close distance.
Edit: (someone could classify a Class 4 diode laser array for heat treatment as an LED array now (given shitty M2) and avoid the laser norms altogether, despite the thing still being dangerous)
We won't. It's been a while since I compared the muzzle energy of a rifle bullet and that of a relatively powerful laser, and I don't have the time to dig up the comparison again right now, but the tl;dr: is that we won't see an even theoretically man-portable laser that can put a hole through someone for a very long time, if ever. Setting things on fire and damaging light sensors, sure - but those tasks are absurdly easy by comparison with rearranging bulk matter.
BUT, all of that can be managed with shielding, eye protection, and walls. When the laser is on, I've rigged mach 3 (CNC control) to turn on some lights at the top of my staircase so that nobody comes into the garage without protective eyewear. It is absolutely possible to be safe without also limiting all your freedoms. In general, safety standards and workshop use-cases are well aligned, and if safety is too much work then a lack of safety is not about freedom, it's about laziness.
AvE has also taken a crack at Cubiio, and I think it is worth repeating some of his points, and my own observations here.
1. Diode lasers for engraving are VERY sensitive to focal length changes. If my surface that I am engraving changes more than 1-2mm in height, I try to compensate for that in the engraving tool path. My minimum line width is .01" with the laser/lens combo I have, and if I am out of focus even .125" (3mm), the line width will probably double.
2. many materials reflect terribly while cutting. Especially pre-finished light colored woods like maple. There is practically no way to avoid this. If I cut those I'll often end up with uncut areas in the piece because 100% of the beam ended up scattered, and didn't manage to burn the piece at all.
3. the idea is very tempting. It would be very nice to have this functionality, but, for the average maker, I think you would be pretty unhappy with the power this can make. I frequently want a LOT more than 4W, this appears to be about 1/4 of that. Most commercial systems from Epilog start at 20-40w. The Cubiio would probably produce shallow, uneven cuts at very slow feed rates with really long run times to produce anything useably deep. If you ran it at faster feed rates it would probably produce a laser engraving so shallow that it would rub off.
4. I want their app. The ability to turn scanned art into vectors for G code is something I would pay for. AFAIK there is NO good commercial solution for this. I have tons of line art that I would love to laser engrave but have no way to produce simple paths from it.
Edit: this is the laser I have - https://jtechphotonics.com/?product=3-8w-laser-and-2-5amp-sa... - I can vouch that it is well made and the vendor is great to work with - he assembles these himself and takes safety seriously.
It seems diode lasers are up to 60% efficient?
It looks like you can get extremely high power pulsed laser arrays though.
And what about the bit where he says that it's "the wild west" (mythicized time when, in actuality, homicide rates were not really that high, especially for the time) or "mad max" (completely fictional Australian motor fantasy).
The things that actually prevent laser related injuries from being a common health problem are a) common knowledge about laser safety (usually explained thoroughly by manufacturers), and b) the relative obscurity and lack of particular interest in high powered laser devices.
edit: if it's not obvious this is a joke
Edit: Is it the Stavatti device you're referring to? Apparently there are some claims that it was a hoax.
Not that it really matters in my case: I will probably scrap the project when/if I make a good enough amplifier stage and phase detector for short range where 5mW should be enough.
Admittedly I've never looked into those issues because the gadgets that I've helped design are all Class 1 -- the system is fully enclosed and interlocked.
[0] Which to me has always been one of those "hard to believe things" and, indeed, I've never worked with an IR laser or tested this (nor would I be interested in doing so) but I can't think of something more terrifying (related to blindness, anyway) than walking into a room, looking at something, seeing nothing particularly interesting and then ... seeing nothing at all ever again.
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 oww! that's bright!" that we are familiar with.
[1] the sound is a spot on the retina explosive boiling after the laser heated it extremely rapidly past 100C
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.
https://en.wikipedia.org/wiki/Convention_on_Certain_Conventi...
A decent hardware hacker could build an area-denial laser turret in a long weekend with a couple of hundred bucks of parts. I hope to god that nobody ever does.
a) you can't see when you're being shot at b) it suffices if there is a sufficiently large (to you invisible) reflection within your field of vision c) you can automatically scan a whole field very quickly, invisibly, silently d) the laser spot gets larger at a distance, so the laser is not a pointer but a shotgun cone with 2m diameter
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).
It might also cause damage to the lens and lead to cataracts, which can also be partially compensated today by getting a lens implant.
These ways of damaging your eye are extremely more preferable than having your retina or your nerves damaged in any way, since for that, no method of remedy exists yet.
I wouldn't call that "humane", and it is a guess; it might not work at all. Nothing to do with war is 'humane', though.
I think what I was trying to say is that if I could choose the wavelength to hit my eye, I'd pick extreme UV.