A way to return LOHAN to the ground, if everything else fails!
Once a year, El Reg's Special Projects Bureau compiles a hardware/office supplies acquisition list for the coming 12 months, which is ceremoniously laid before management in the hope the Vulture Central coffers are particularly cornucopious. The trick is to slip in the more provocative items amid the usual litany of …
forget mr BMW with HIDs, a large number of cyclists in rural areas have absolutely BLINDING lights strapped to their heads.
Seriously - it's no fun having green spots in your vision when you're driving at night after passing one of these. If these were on cars they'd fail their MOT and/or result in roadside impoundment (There are standardsdefined for bike lights but most of the ones I encounter seem to be repurposed 3-5W MR16 Leds with no consideration for beamwidth by the users.
At least you have the option to buy them.
Here in the People's Nanny State Republic of Ausfailia, the government, in its never-ending quest to wrap us all in the cotton wool of paranoid safety, has classed all lasers over 1 mW as controlled firearms, and it's illegal to own, sell or import them into this pathetic fucked-up cuntry (spelling slip intentional).
Just another reason why I recommend against coming to this police state on holiday. Go to China instead. There's more to see, it's more free and you're actually allowed to own lasers there.
actually, i want two! i'm so jealous!!
although, at $1200 for the kit you had, it'll be some time before i'm ready for a jedi battle...
are these powerful enough to use as a means of lifting a craft into the sky? i seem to recall seeing something on telly... was it a James May show? where these guys in the States were pulsing a laser directly into the sky, and placing a silver bowl into the beam lifted it up into the sky
Hah, newlyweds!!! It's a wonder anyone stays married these days.
Seriously, any man worth his salt knows that you go out and buy the laser, then give it to your best friend, who then re-gifts it as a wedding present!! You can even go for wife brownie points by offering to help with the post-wedding thank you cards (which also serves to cover up the agreement).
Here, let me help you with the thank you salutation:
XXXXX and I want to thank you for the thoughtful gift of the Mark 9000 HyperLaser with optional Jedi Knight package. This will definitely come in handy the you for next time my sweetie wants me to kill a spider on the ceiling, start the fireplace when I don't want to get off the couch or scorch our initials and protestation of undying love into the side of the local highway overpass. I'm actually looking forward to my honey's and my first argument, where I can add the Jedi Knight package and warn her "You can't win baby! If you strike me down, I will become more powerful than you can possibly imagine!!" In short, this gift will be at least as useful as the chafing dish we got from my in-laws or the three sterling silver tea sets that we now have to return.
It's generosity like this that makes you like a brother to me, and I'll let you know when XXXXXX stops thinking you're an irresponsible 12-year old and is OK with you actually coming over."
Congratulations on the now-guaranteed success of your marriage, and "with you may the Force be"!!
If you can build a pulsed laser powerful enough then you can lift an entire spaceship with one.
Bell shaped chamber at the bottom, shine the (pulsed, this is important) laser in there and you've got lift. Once out of the atmosphere you'd need to be boiling something to continue accelerating. Caesium would do nicely.
Not that I know anything about the science or engineering of this of course. All comes from an old Jerry Pournelle story/
It's much more than just a Pournelle story. There's various suggestions for laser propulsion, one of the neat ones uses ice as the propellant. Blast that with a really big laser and the steam pushes your spaceship. All the big mass stays on the ground and doesn't have to be lifted. And all the complicated bits stay on the gropund where your engineers are.
The first studies on this were by Arthur Kantrowitz. There has been some practical work on it, in particular by Jordin Kare - I asked him about it once and he told me that the system is practicable and just needs enough investment.
There's a video of a prototype laser-pumped vehicle here:
Of course, the laser is ex-SDI antisatellite laser and is stupidly powerful (there's a scene where it rips the hell out of a paper target), and the vehicle is a tinfoil toy and gets maybe 10-15m into the air, but it does show the technique works.
"not to be a killjoy, but what are the practical uses for a consumer to own one of these? apart from "holy shit, its cool" These seem incredibly dangerous."
Of course they are dangerous and would have someones eye out --
That's the point .
(Cars are also great toys but tend to kill if pointed indiscriminately at people and operated)
"(Cars are also great toys but tend to kill if pointed indiscriminately at people and operated)"
I would hazard that cars have a practical value.
I'm not sure what the honest practical value of this other, other than "Wa-hoo, this is awesome!" [which it is, but I'm not sure I want it to be available for purchase for people with sub-100 IQs!]
The power rating of these are one reason that they are illegal to buy and sell in the UK without the correct licence, in fact anything over 1mW (it used to be 5mW) is liable to be stopped on import (if it's for resale, personal imports should still be OK), because of the frequency the green ones are particularly dangerous (more damaging than red of the same power, 200mW will cause perminent damage faster than the blink response), contary to popular belief they are not illegal to own, but do anything stupid (like shine at unprotected eyes or aircraft) you could be looking at prison.
"contary to popular belief they are not illegal to own"
Going from 5mW to 1mW is truly Nanny State stuff which I certainly don't agree with, but ready access to 1W devices shouldn't be possible. As with guns, lasers >200mW are potentially very dangerous and should be licenced and the licensee appropriately trained (and such lasers kept under lock and key a la armory procedures). Moreover, unlike a rifle where every round fired is the result of a deliberative action by the shooter, a laser's continuous wave output combined with that it can be swung through an arc makes it particularly dangerous.
My concern is that now these devices are commercially available it means that those with ill intent will obtain them one way or another, and after a few people are blinded by the fuckwitted action of others--and as sure as eggs they will be, then the Nanny State will make it almost impossible for the legitimate user to gain access them.
A few months ago I was going into a small club (well, pub with dancefloor) and some diminutive twat of a bouncer had a little green laser and was now and then shinging it onto women's backs as they went in, while wearing apeish smirk. It made an amazingly bright little green dot - I would not have wanted that in my eyes even though it *probably* would not have done anything permanent. It was pretty impressive even when just scattering off clothing from a few feet away though.
I just don't see the practical value of such a thing, unlike e.g. cars. There are too many dangerously stupid people in the world, perhaps like those who play with such lasers in the presence of children (no I don't think the shades were adequate protection, at all).
FTR <http://www.newscientist.com/article/dn14310-party-laser-blinds-russian-ravers.html>. I recall that the laser was 'a few watts' (no more specific details and my memory may be wrong).
Prison yes - IF you can catch the bastards.
I got flashed with a high power green laser while driving a few months back, by a wanker standing outside a pub. Cops called by about 10 different drivers. By the time they arrived he'd also targetted a few aircraft on their way into Gatwick - but he stepped into the pub and couldn't be found.
quote: "not to be a killjoy, but what are the practical uses for a consumer to own one of these? apart from "holy shit, its cool" These seem incredibly dangerous."
So are shotguns, and they are perfectly legal to purchase and operate in the UK, if you can be bothered spending £50 on the certificate and have a nice talk with the local firearms officer about responsible use of firearms. They can be considerably cheaper than these lasers, too.
Also, anyone with a working knowledge of physics can construct their own laser from a collection of perfectly legal components. CO2 (that demon gas) creates an infrared laser that can be easily used to ignite things at a high enough power, invisible Martian "heat-ray" style.
So, those things considered, your point was that you think a high powered laser could potentially be dangerous, and I am assuming the unwritten portion of your thoughts was that they should therefore be regulated somehow. Might I suggest the shotgun or firearms certificate as a good starting point? That would make sure only criminals have unlicensed lasers, after all :)
Heh... firearms certificates required for a CD-ROM, that would be classic nanny state :D
... No they won't stick to their £5 tat. They'll be impressed that these things can pop balloons, or burn stuff, and want the higher powers. What El Reg bought was a precision machined aluminium device that is tested and comes with safety instructions and glasses. What the chavs will buy shall be cheap chinese crap off ebay with no safety and no true measurements or testing.
There is no need for these things - anything above say 5mw should be banned outside of licensed industrial use. This comes from me as an engineer that is interested in using lasers, and the higher power ones too (free space optics), but I don't see a problem with being charged a one off cost for a license. This will dissuade idiots from buying, and give the authorities something hard to crack down against when people sell these items.
These must be standard in every laser lab. My partner did a chemistry masters at Oxbridge and they had one.
They also had a load of service technicians who had points of vision missing because they got complacent. It's very, very easy to get complacent, it's also very easy to forget that a laser will knacker your vision above only a few milliwatts.
No, it's quite believable. Even a cheap "toy" 1mW red laser pointer can, with careful adjustment of the focus, produce a spot which is visible from 100 metres.
A laser is a point source and very tightly collimated, so the beam of light is a cone -- but one with a very, very small angle (the kind of angle where you don't bother distinguishing between θ, sin θ and tan θ anymore). The energy in the beam is distributed over the cross-sectional area of the base of the cone. Which, precisely because the angle is so narrow, doesn't vary much with distance.
Considering that incidents of lasers shone at planes on approach or police helicopters are on the increase in the UK, it's not particularly a good idea to be trumpeting the powers that this gadget has.
Not only is it illegal in the UK (because of its power output), but it is dangerous in the hands of a non-professional (your daughter excluded, since she has a dad who is a professional).
As much as it looks like a lot of fun, I'd prefer my pilots to be able to see things in the last few miles on approach into an airport, thank you very much.
"I'd prefer my pilots to be able to see things in the last few miles"
Me too. We were standing on the beach in the south of France a few weeks ago - very dark, beautiful starry night, far from any serious light pollution and then suddenly a brilliant green beam started up from inland pointing up and out into the med. sky. It flashed all over the place for about a minute, no obvious pattern like a laser light show, and then stopped. What it might have done to a pilot or even a sailor doesn't bear thinking about.
"For real penetration, though, check out the stats on the 532nm green Krypton. At full power, its NOHD is the same as the Arctic - 149m. However, its FL1 is a staggering 137,120m."
To give that some perspective, that is 85 miles.
I can see few reasons why anyone working outside of an industrial or research setting using such lasers would need something that can project a visible spot of light onto a building in London, from Swindon.
I have one of those cheapo green lasers I got off Ebay a while ago. Can't remember the output (not to hand to check). Think it was well over 1mW though. Might be 3 or 5 not sure. Anyhow the first time I had it I was playing with it indoors and decided to shine it out into the dark outside the back window. Silly me forgetting to open it first and that that glass is reflective. I ended up being zapped in one eye. I had a bright green blob on the back of my retina for a good hour or more. Luckily I don't think I did any lasting damage but it was a good warning of just how dangerous these things can be.
As i own the Dragon lasers spartan 1w blue laser,( a better quality item than the shit wicked lasers pump, no pun intended, out) , a 500mw green laser, 300mw red and a 2.5w IR laser the one thing that has been overlooked is the quality of the optics.They are shite and the beam divergenge is massive. At 100 meters the "spot" is about 2-3 inches across, at 500 meters its about a foot....
Also, none of these operate in true TEM00 mode.......
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