Are laser pointers LEDs or real lasers?

[beer]

I shined a laser pointer by accident into someone's eye and he went off on me saying how they can destroy your cornea, and pointed to the warning. I said yes, the warning is there, but it is really just an LED, just like an optical mouse.

Who is right>

 

[Mikal]

They are real lasers. Low power but don't take chances.

 

[Vikaden]

yes they can destroy your eyes, i hear its worse than looking right at the sun

 

[GL]

I think he's right. If you did it long enough (not sure how long) it could do some damage. They're definitely real lasers.

 

[randal]

yea, they are real lasers ... and they are quite damaging ... lots of people get screwed up vision every year because of them.

though i still think they're cool =)

randal

 

[Killbat]

They are solid state, like LEDs, but they do actually put out REAL LASER LIGHT. Light emitting diodes put out a small range of wavelengths, not in sync. Laser diodes put out a specific wavelength, in sync.

 

[zzzz]

dude, don't point them at anyone's eyes. They are real and powerful enough to destroy eyes.

 

[phry26]

I have a friend who got sued by a teacher of his for shining a laser in his eye for a split second. The teacher complained of spliting headaches and the like later.

Not that anyone cares I was just looking for any reason to post my 20th and become a member and get the respect I deserve for once.

 

[phry26]

Mabye one more then.

<---------And my parents told me I would never amount to anything!

 

[chiwawa626]

an led is totaly diffrent

 

[mrCide]

very very bad.

 

[DannyLove]

i dont even know how LEDs came into your brain. You're telling me that you can shine a LED several feet in distant. omg... it has to be lazers man, think, and STOP SHINING it in other peoples eyes, if I was your friend, I would have kicked your ass

danny~!

 

[chiwawa626]

DannyLove, howcome i cant see ur sig?




















j/k

 

[Linux23]

poppycock, i shown one of those in my eyes for minutes at a time and it did nothing to my vision.

 

[FreeFrag]

<< poppycock, i shown one of those in my eyes for minutes at a time and it did nothing to my vision. >>



Hmmmm.....One question: WHY? What if it did do something? (What if it HAS?)
Linux23, find something else to do

 

[Linux23]

heh, i guess i was bored that night. i had 3 laser pens, and i was creating a laser light spectaculer in my room on the ceiling. that was fun!

i guess we'll see in a few years what effects it had on my vision!

 

[MWink]

It's funny, everyone I know says optical mice have lasers (not LEDs). I'm getting really sick of correcting them.

BTW, does anyone know how damaging CD/DVD-ROM lasers are when you look into them?

 

[RossGr]

There is a standard for classifing the hazard level of lasers, form class 1 the lowest hazard level up to class 4(?),I am not really sure of the highest level. It is an OSHA requirement that here be no EXPOSED lasers in the work place greater then class 1. My laser pen is labled class 2 so on the OSHA scale these would not be allowed in the work place without containment pecautions. It says on the box of my LASER poiner &quot;DO not stare in to the beam&quot; this implies that most people will not suffer eye damage to a quick flash to eyes, they will not put your eye out instantly. As far as I am concerened it is impolite to shine a FLASHLIGHT in someone eyes to flash them with a LASER is beyond impolite is simply should not be done.

Yes, solid state LASERS are also LEDs but they emit a nearly monochromatic coherent beam which has a very small divergence, this differs from a normal LED which may be nearly monochromatic but is not coherent. Cohereance it the property which creates the tight beam, this is where the danger lies, the beam is small enough that the full beam diameter can pass through the pubil of the eye, so the full power of the LASER hits the retina. I would think that the mere possibility of doing eye damage would be enough to prevent you from pointing one of these at someones face. I personally think that kids should not be allowed to have them.

 

[frizzlefry]

The above post is pretty much correct. Certain wavelengths of light can cause more damage than other. I worked with CO2 (carbon dioxide for non science ppl) lasers for about 3 years. This specific wavelength is highly absorbed by water. So while working with these, it is required to use protective eyewear. We had a sign on our lab doors, you only have one set of eyes and they aren't replaceable. We were working with 20W to 60W lasers over a whole spectrum also doubling the frequency to produce different wavelengths. I srewed up my eyes one time for a couple days because I didn't realize that the diode pumped laser was putting out green. You just can't see it when it's invisible.

Although we're talking about a 3-5mW red diode laser, it is still pretty dangerous to shine it in someone's eye. At these levels however, it would take quite a bit of time before any significant damage may occur. Spots are probably the longest lasting. The reason these are dangerous is because the beam does not diverge enough. Its a pretty well collimated beam coming out of these and your eye is sensitive to red. So best thing is just don't shine any laser into anyone's eyes. You won't get slapped for it and you can avoid causing any injury.

 

[Thegonagle]

To answer the question about CD/DVD-ROM lasers, they're not super bad because they're focused to a point 1-2 mm from the lens, so if your eyeball is several inches away, the laser energy is pretty well dissipated. (SEE MY NON-ARTIST'S RENDERING)


.\ | /
. \|/
. /|\
lens
. |||
. |||
. |||
. |||
. L .
. a .
. s .
. e .
. r ..

CAUTION:
The wavelength of a CD laser is almost invisible, so don't make a habit of powering up dissected CD/DVD drives and staring at the lens. Though you can barely see it, it can still be quite &quot;bright,&quot; especially CD-R/RW lasers.

 

[ManSnake]

They are weak lasers.

 

[RossGr]

<< They are weak lasers >>


At 3 - 5 mW they are significant, treat them like a loaded gun, NEVER point them at anyone.

 

[MWink]

Garfang: That was what I was thinking. I actually took one apart and was playing with the lense with a flashlight (the LED was unpowered of course). I was just checking because some of my friends have been playing with open CD-ROMs lately and I was a little worried.

 

[HomeBrewerDude]

an LED wouldn't maintain a tightly focused beam. only a LASER can do that...i guess you could use a system of lenses to continuously adjust for a moving focal point but that would be prohibitively expensive.