"Our results show that the so-called 'frequency doubled' laser pointers, usually green, blue and violet pointers, can be particularly dangerous even if they seem safe to the user," he said.
"For example, some laser pointers can output widely different laser power depending on the temperature. They can appear perfectly safe at room temperature only to become much more dangerous outside and vice-versa. Moreover, as pointers are being used they heat up, so a pointer that initially seems safe can subsequently become highly powerful and dangerous.
"Other lasers can produce safe levels of coloured light, but at the same time emit high power invisible infrared light. A person looking at the visible green light would estimate the laser to be safe and the much greater power and danger would go unnoticed until injury occurs."
Laser pointers have been controversial, in particular because they have been shined into the eyes of plane and helicopter pilots and train drivers, with an average of 1,500 reported attacks per year in the UK. They can cause permanent or temporary eye damage, and it is a criminal offence to do so.
If they're so dangerous, why are they putting them in the headlights for all the new cars?
(Score: 0) by Anonymous Coward on Wednesday October 11 2017, @12:09PM (14 children)
I really hate it when someone uses a green pointer during their presentation.
It's way too bright.
I have no idea why people even buy pointers that are not just plain red.
With brand new batteries, those are borderline acceptable as well in terms of brightness...
(Score: 3, Informative) by Anonymous Coward on Wednesday October 11 2017, @12:13PM (9 children)
The green ones are nice if you are pointing out objects in the night sky to someone.
(Score: 2) by CoolHand on Wednesday October 11 2017, @12:44PM (4 children)
It's why I bought one.. They're awesome for that.
Anyone who is capable of getting themselves made President should on no account be allowed to do the job-Douglas Adams
(Score: 5, Funny) by DannyB on Wednesday October 11 2017, @01:33PM (3 children)
Laser pointers are especially useful for pointing out aircraft in the night sky.
(ducks, hides under desk)
To transfer files: right-click on file, pick Copy. Unplug mouse, plug mouse into other computer. Right-click, paste.
(Score: 2, Funny) by Anonymous Coward on Wednesday October 11 2017, @02:46PM (2 children)
You've got ducks and hides under your desk?
(Score: 5, Funny) by kazzie on Wednesday October 11 2017, @02:58PM
Do I need to point them out with a laser for you?
(Score: 3, Funny) by bob_super on Wednesday October 11 2017, @05:53PM
Winter IS coming, you know...
(Score: 2) by ledow on Wednesday October 11 2017, @02:54PM (2 children)
Pretty sure any amateur astronomer would wrestle you to the ground if you're shining bright green things around, as opposed to "night-vision friendly" red stuff.
(Score: 1, Informative) by Anonymous Coward on Wednesday October 11 2017, @04:01PM (1 child)
Nope, even the green ones (assuming legal <5mW power) are dim enough to not be a problem when you shine them up in the sky, because you only see the backscatter. Now if you shine it on nearby objects, sure, it would be bad. So don't do that.
(Score: 2) by bryan on Wednesday October 11 2017, @06:20PM
Oblig xkcd [xkcd.com].
(Score: 0) by Anonymous Coward on Wednesday October 11 2017, @09:25PM
Like airplane cockpits?
(Score: 2) by fraxinus-tree on Wednesday October 11 2017, @12:30PM (2 children)
Green lasers are expensive, or at least used to be, back then. That's why most people buy them. Red ones are just OK.
(Score: 2) by Snotnose on Wednesday October 11 2017, @02:33PM (1 child)
I paid something like $150 for my green pointer some 10-15 years ago. Now you can get them for $10.
I also paid around $100 for my red pointer when they first became available. Now the dollar stores have them for $0.99.
When the dust settled America realized it was saved by a porn star.
(Score: 0) by Anonymous Coward on Wednesday October 11 2017, @05:02PM
And how much did you pay for all those gold chains, mister big spender?
(Score: 2) by urza9814 on Wednesday October 11 2017, @05:37PM
Even the red ones seem too bright to me. Even the tiny ones they sometimes build into projector remotes. It's alright if used sparingly just to point out one or two things, but if I'm looking at that dot for more than a few seconds it starts to hurt my eyes. Some people will just leave the laser pointing at the screen for an entire presentation/lecture and then I miss half of it because I can't bear to keep my eyes on the screen...
(Score: 1, Interesting) by Anonymous Coward on Wednesday October 11 2017, @12:31PM (3 children)
> If they're so dangerous, why are they putting them in the headlights for all the new cars?
That is simple - people tend to solve problems in the "most efficient" way - but not necessarily smart or safe ways.
For example: the shoe-fitting fluoroscope made it very easy for salesmen to make sure a person's shoes fit properly, but those things were NOT safe ... and it took a while to figure out there was a problem.
(Score: 2) by kazzie on Wednesday October 11 2017, @03:03PM
Given that the fluorosope showed foot bones and none of the surrounding tissue (which is important in esablishing shoe fit) I think there was more marketing gimmick involved than efficient fitting technique.
(Score: 3, Funny) by deadstick on Wednesday October 11 2017, @03:19PM (1 child)
I loved those as a kid. They actually made me want to go shopping with my mom.
(Score: 2) by Gaaark on Wednesday October 11 2017, @03:53PM
same same!
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 3, Informative) by fraxinus-tree on Wednesday October 11 2017, @12:32PM (19 children)
Lasers in headlights are completely different matter. You generally don't get laser beam of any kind outside and the light output is controlled.
(Score: 3, Informative) by Anonymous Coward on Wednesday October 11 2017, @01:31PM (14 children)
http://auto.howstuffworks.com/laser-powered-headlight.htm [howstuffworks.com]
(Score: 2, Insightful) by Zipf on Wednesday October 11 2017, @02:19PM (10 children)
.. except white light tends to have a significant blue component that wipes out night vision and possibly depletes melatonin. I would like to see regulation surrounding lumens below for wavelengths below 480nm for cars and 500nm for street lights.
(Score: 3, Touché) by ledow on Wednesday October 11 2017, @02:55PM (6 children)
If you're relying on your night vision to drive, you're doing something wrong.
That's precisely why we invented headlights.
(Score: 0) by Anonymous Coward on Wednesday October 11 2017, @03:05PM
(Score: 5, Informative) by Thexalon on Wednesday October 11 2017, @03:13PM (4 children)
Of course you are relying on night vision. Your headlights show you some of what's in front of you. They don't tell you what's next to you or what's behind you. Your pupils dilate quite a bit, even with your lights on. And then some jerk comes the other direction in an illegally jacked-up pickup truck with super duper bright halogen lights and your pupils now have to close up again. And it takes them a while to dilate again.
A recommended move when somebody like that is coming towards you is to look at the line on the side of the road (or the side of the road itself if there is no line there) when they get close so that your pupils don't close up as much while still telling you which way to stay on the road.
The only thing that stops a bad guy with a compiler is a good guy with a compiler.
(Score: 2, Informative) by Anonymous Coward on Wednesday October 11 2017, @04:30PM (1 child)
"Night vision" is a poorly-defined term, so I'm not saying you're wrong to use it that way, but it seems to be causing confusion in this thread.
Usually, people people use "night vision" to mean scotopic vision, which is very slow (minutes) to recover, and leaves you essentially blind. If you were driving by scotopic vision, and got headlights flashed in your eyes, you would be pretty likely to crash or run off the road. Fortunately, if you're driving with any headlights (even crappy optics with decade-old long-life bulbs in them), you're not using scotopic vision.
Ordinary pupil dilation/contraction that you refer to is a much faster process (seconds), and while recovering, you'll still have some visibility in the brightest and/or closest part of your headlight beams; you will be overdriving your headlights (as seen through your contracted pupils), so there's certainly some potential for a crash in those seconds, but you're unlikely to run off the road.
(Score: 2) by Phoenix666 on Wednesday October 11 2017, @05:45PM
There are the after images to contend with, too. Even with your mirror flipped the halogens are blinding and cause your vision to dance with those after images. When they're coming the other way on the other side of the highway, with no blinds to prevent it like they have on the autobahn, it's even worse. Looking at the sideline the way they taught you when seeing high beams on old style headlights isn't enough; you have to try to screen them out with your hand.
Washington DC delenda est.
(Score: 2) by number11 on Wednesday October 11 2017, @07:15PM (1 child)
Aw... I'm not supposed to use the RPG?
(Score: 2) by hendrikboom on Thursday October 12 2017, @12:53AM
The role-playing game? I suppose you could do that while you're parked by the side of the road waiting for your eyes to recover.
(Score: 2) by fraxinus-tree on Wednesday October 11 2017, @03:00PM
I sometimes dream of that, too. The evil first materialized as aftermarket xenon headlights, then LEDs and now lasers. In the meantime, I wear those yellowish blue-light-protecting glasses when driving. It helps.
(Score: 0) by Anonymous Coward on Wednesday October 11 2017, @04:06PM (1 child)
Depleting melatonin is good -- do you want people to fall asleep at the wheel?!
(Score: 0) by Anonymous Coward on Wednesday October 11 2017, @07:54PM
I want driverless cars to replace all human drivers.
(Score: 4, Insightful) by Anonymous Coward on Wednesday October 11 2017, @02:44PM (1 child)
If they had the CEO do it, I might have been more impressed. Or even better, the CEO's own child (assuming it can be established that the CEO loves the child).
(Score: 4, Insightful) by Gaaark on Wednesday October 11 2017, @03:55PM
Yup: engineers are cannon fodder. The CEO's kid may be disposable, depending on the CEO. Make the CEO do it and do it for an hour.
--- Please remind me if I haven't been civil to you: I'm channeling MDC. ---Gaaark 2.0 ---
(Score: 2) by requerdanos on Thursday October 12 2017, @01:42AM
The chemical company stated on its website: "The intensity of the chemical poses no possible risks to humans, animals, or wildlife"
Who you gonna believe? Consider the source.
(Score: 4, Informative) by EvilSS on Wednesday October 11 2017, @01:59PM (3 children)
(Score: 1) by fustakrakich on Wednesday October 11 2017, @03:46PM (2 children)
The laser is used to excite a phosphor
I wonder if they could make a TV screen out of that...
La politica e i criminali sono la stessa cosa..
(Score: 2) by LoRdTAW on Wednesday October 11 2017, @04:03PM
https://en.wikipedia.org/wiki/Laser_video_display [wikipedia.org] Though it uses colored beams instead of phosphorus as it's similar to a projector, not a CRT.
(Score: 2, Funny) by Anonymous Coward on Wednesday October 11 2017, @05:28PM
Yet another valuable fustakrakich post wherein the content-free conundrum could have been solved in a couple seconds by a capable user with an Internet search engine.
(Score: 5, Informative) by Thexalon on Wednesday October 11 2017, @01:51PM (2 children)
Do not look at laser pointer with your remaining eye.
The only thing that stops a bad guy with a compiler is a good guy with a compiler.
(Score: 2) by LoRdTAW on Wednesday October 11 2017, @04:04PM (1 child)
Do not taunt green laser.
(Score: 0) by Anonymous Coward on Wednesday October 11 2017, @05:31PM
Green laser may stick to certain types of skin
(Score: 5, Funny) by wonkey_monkey on Wednesday October 11 2017, @04:30PM
Well I just called a biochemist to tell him, but he wasn't interested. Oh well.
systemd is Roko's Basilisk
(Score: 3, Insightful) by nobu_the_bard on Wednesday October 11 2017, @05:26PM
Unwittingly, you say?
You're sure it's unwittingly?
(Score: 2) by bob_super on Wednesday October 11 2017, @05:57PM
Those colors are for losers anyway.
I only use 1310nm or 1550nm, Class 3B or Class 4, lasers as pointers. Infrared FTW!
(Score: 0) by Anonymous Coward on Wednesday October 11 2017, @06:25PM (2 children)
Some idiot shined one of these down the street toward me one night. At first I looked toward it, mistaking it for police lights. That could have hurt my eyes.
On the other hand, I could use a powerful laser for trimming high tree branches and for getting cats out of my yard.
Maybe we could just ban the idiots.
(Score: 0) by Anonymous Coward on Wednesday October 11 2017, @11:10PM (1 child)
I think banning hand-held Class 4 lasers should suffice.
You are supposed to have a room interlock on those.
(Score: 1, Funny) by Anonymous Coward on Wednesday October 11 2017, @11:50PM
Room interlocks would interfere with trimming high tree branches and getting cats out of my yard. I kind of need it hand-held too, though two hands would be fine. I'm OK with needing a power cord; that is actually better than batteries.
Trimming branches probably needs a tripod mount and a motor to slowly move the beam.
An ideal setup for getting cats probably has a targeting scope that filters out the laser light, plus a button to fire a brief high-power pulse. The beam must be wide enough that the power density won't shatter a normal household window. It still needs to singe fur, because otherwise you'd need to hit them in the anus or something.