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View Full Version : NextGen Lasers?



Assassin
Sun, 01-08-2006, 11:11 PM
Wicked Lasers (http://www.wickedlasers.com/)

perhaps some of you have heard of this already, but for those who havnt, its seems to be a super strong laser pointer.

According to the site, the Elite series is powerful enough to pop balloons, burn a hole in a garbage bag and even burn skin.

If anyone has one, or is getting one, can u confirm if the whole burning thing is true. I find it hard to believe something like that would be marketed commercially.

darkmetal505
Sun, 01-08-2006, 11:32 PM
Originally posted by: Assassin


If anyone has one, or is getting one, can u confirm if the whole burning thing is true. I find it hard to believe something like that would be marketed commercially.

true, those could really kill someone. Its not dont point that to someones eye anymore (you point for a second, it aches), its point that and you get your eye burned.

Paulyboy
Mon, 01-09-2006, 12:52 AM
OMG! lol we are all going to die, plus there is gonna be alot of stupid shit people are going to do with it. i/expressions/face-icon-small-smile.gif

Assertn
Mon, 01-09-2006, 01:03 AM
open cut healing power.......?

Assassin
Mon, 01-09-2006, 01:30 AM
as in, burning ur wound closed?

thats pretty hardcore. I wonder how severely it could burn skin.

KitKat
Mon, 01-09-2006, 01:31 AM
Ah lasers. I've built lasers before, but those were infrared, so you coudn't see them. Not half as much fun as these.

The information on the site looks fairly accurate. These are class 3b lasers. Typically, most laser pointers are class 3a. If you get a class 3a laser in the eye, your blink reflex will be enough to save your sight. There's no real danger unless you stare into the beam for a long time. For class 3b, your blink reflex isn't enough. A direct beam in your eye can seriously hurt you, depending on the power of the laser and whether or not it's pulsed. For the ones on this site, it looks as though their most powerful ones are around 125 mW. This will burn things if you hold it on one spot for a significant period of time, but shouldn't be any threat if passes over your skin. You might have trouble importing one of these, depending on what country you live in. You might have to go through a bunch of paperwork that justifies your use of them. I wouldn't recommend using one of these unless everyone nearby was wearing protective laser glasses. The lower power ones though, that are just above 5 mW shouldn't be particularly dangerous.

Jaredster
Mon, 01-09-2006, 02:16 AM
Since kids are already notorious with laser pointers, this is the last thing they need.

Kraco
Mon, 01-09-2006, 04:19 AM
In the end, I'm pretty happy there is the ~5 mW max output general rule. Of course I would never misuse a more powerful laser (just like I have never misused my 5 mW pointer), but I don't trust the other people who might acquire one...

el_boss
Mon, 01-09-2006, 07:39 AM
Omg we are getting closer to having lightsabers in every home.

Deblas
Mon, 01-09-2006, 02:01 PM
They're actually selling these? Why in blazes do we need a more powerful laser to just point things with??

Kraco
Mon, 01-09-2006, 02:37 PM
After reading the website, it seems to me their main reasoning is just to boost the power to make the beam more visible. I suppose it makes sense that you need less particles in the air if the light intensity grows. And likewise background lighting affects in a lesser extent. As we (probably) all know from personal experience, the 5 mW red laser needs quite a messy air to make the beam visible.

aznimperialx
Mon, 01-09-2006, 03:23 PM
i've always hated those stupid bastards in class who played around with the lasers. Now its going to be worse

aznroyale
Mon, 01-09-2006, 03:39 PM
ppl gonna get blinded if they got shot in the eye....25 times brighter than regualr lasers
so carry with a magnify glass....even more dangerous -_-

Board of Command
Mon, 01-09-2006, 04:00 PM
Doesn't the laser have to hit something at the focal point for it to actually burn...? Think of burning CD's for example. It's strong enough to penetrate the plastic and gouge the actual disk, but it doesn't melt the plastic because it's only focused at the point of contact with the actual disk. I've used a very strong laser before and no matter where I placed my hand, I couldn't feel anything.

It damages the eye not because it's hot, but because it's so bright that it damages the sensory nerves inside your eye. Am I wrong about this whole focal point thing?

Carnage
Mon, 01-09-2006, 04:01 PM
This company WILL be either sued or shut down. There are going to be so many accidents......

Ero-Fan
Mon, 01-09-2006, 05:14 PM
Originally posted by: BOARD_of_command
Doesn't the laser have to hit something at the focal point for it to actually burn...? Think of burning CD's for example. It's strong enough to penetrate the plastic and gouge the actual disk, but it doesn't melt the plastic because it's only focused at the point of contact with the actual disk. I've used a very strong laser before and no matter where I placed my hand, I couldn't feel anything.

It damages the eye not because it's hot, but because it's so bright that it damages the sensory nerves inside your eye. Am I wrong about this whole focal point thing?

I believe you're right about that. But if the kid has a magnifying glass or mirrors, couldn't they make their own focal point for the laser?

KitKat
Mon, 01-09-2006, 06:14 PM
Originally posted by: BOARD_of_command
Doesn't the laser have to hit something at the focal point for it to actually burn...? Think of burning CD's for example. It's strong enough to penetrate the plastic and gouge the actual disk, but it doesn't melt the plastic because it's only focused at the point of contact with the actual disk. I've used a very strong laser before and no matter where I placed my hand, I couldn't feel anything.

It damages the eye not because it's hot, but because it's so bright that it damages the sensory nerves inside your eye. Am I wrong about this whole focal point thing?
Focal point is kindof a relative term. Some light sources, or sources in combination with lenses have a minimum focal point. That is, there is a spot size that is the smallest possible, you can't reduce it down to zero. If you have a perfectly collimated beam, it will have a focal point of infinity since the rays will never converge. In general, laser pointers try for this perfect collimation, but in actuality are slightly diverging. This is why your laser pointer beam gets larger and fuzzier at greater distances. Now, you can use a lens to focus the beam. What this does is it increases the power per unit area. Five milliwatts over a 1cm radius isn't going to do very much, but once you have five milliwatts concentrated to a spot of half a millimetre radius that spot starts to heat up. You're delivering more power to it than it can dissipate, and it absorbs this power and starts to burn (speaking of a generic flammable material of course....every material will have a different heat capacity, rate of heat dissipation and rate of absorption of photons, etc.). So you could be using a 10 Watt laser, but if the beam is really large, it won't do much more than a tiny laser pointer.

For these lasers advertised, they would need to be held for a while on a single spot to make it burn. The rate of heat absorption needs to be greater than the rate of heat dissipation, and this ratio will determine how fast your material will heat up.

And from what the webpage says, it seems as though the buyers of these lasers want them mostly for commercial or industrial applications as tools or aids in experiments. They specifically caution against using them as laser pointers.

Kraco
Mon, 01-09-2006, 07:00 PM
Heh heh. Good thing I never posted the text I had already written as an answer. Although it contained pretty much the same things (in theory), yours is 1000% better.



Originally posted by: KitKat
And from what the webpage says, it seems as though the buyers of these lasers want them mostly for commercial or industrial applications as tools or aids in experiments. They specifically caution against using them as laser pointers.

Those things are probably there just for the lawyers. We all know their primary customers are rich kids and delinquent adults...

ChaosK
Mon, 01-09-2006, 08:01 PM
edit: nevermind.

Board of Command
Mon, 01-09-2006, 10:53 PM
Originally posted by: KitKat
Focal point is kindof a relative term. Some light sources, or sources in combination with lenses have a minimum focal point. That is, there is a spot size that is the smallest possible, you can't reduce it down to zero. If you have a perfectly collimated beam, it will have a focal point of infinity since the rays will never converge. In general, laser pointers try for this perfect collimation, but in actuality are slightly diverging. This is why your laser pointer beam gets larger and fuzzier at greater distances. Now, you can use a lens to focus the beam. What this does is it increases the power per unit area. Five milliwatts over a 1cm radius isn't going to do very much, but once you have five milliwatts concentrated to a spot of half a millimetre radius that spot starts to heat up. You're delivering more power to it than it can dissipate, and it absorbs this power and starts to burn (speaking of a generic flammable material of course....every material will have a different heat capacity, rate of heat dissipation and rate of absorption of photons, etc.). So you could be using a 10 Watt laser, but if the beam is really large, it won't do much more than a tiny laser pointer.

For these lasers advertised, they would need to be held for a while on a single spot to make it burn. The rate of heat absorption needs to be greater than the rate of heat dissipation, and this ratio will determine how fast your material will heat up.

So does the lens at the front of the laser pointer act as the focus, or does it just provide an emission outlet for the beam and you'd need an external lens to actually make it strong?

KitKat
Tue, 01-10-2006, 12:05 AM
I'll give you guys a crash course in laser operation here, since there seems to be some interest, but I'll try to be as clear as possible without going into a lot of optical theory about refractive index and electron energy bands.

Basically, all a lens does is change the direction of your light rays. It doesn't change the power, it only affects directionality. You can use lenses to do a lot of different things. If you want a fun way to experiment with this, I recommend the Optics Lab Ray Tracing Software (http://www.optics-lab.com/). If you want a free download you might have to look around a bit.

So, let's examine the structure of the laser as outlined on their information page (http://www.wickedlasers.com/about.php). The first component is a diode. Electrical energy is used to excite electrons to a high energy level and when they drop down, they emit a photon of energy corresponding to the energy gap. Judging from the 808 nm light they give, I'd bet this diode is made of GaAs (Gallium Arsenide, if you're wondering - very toxic btw) or some similar semiconductor. GaAs is a great semiconductor that is an excellent light emitter, but almost always in the infrared. When the light escaped from the diode, it is pointing every which way. The first lens is used to collect this light and make it into a coherent beam. This is then sent to a crystal.

*Terminology* You might often hear physicists talk of 'pumping' a laser. This means supplying energy to it in some form so that it can emit energy in the form of light. So when we were talking about the diode, this was pumped electrically. Crystals cannot be pumped electrically, they need to be pumped with light (photons). This way you can input light of one wavelength and have an output of a different wavelength.

So, there are a couple of crystals used in this laser, and at the end we have our green light produced. However, not all of the infrared light got absorbed along the way. A lot of it travelled right through those two crystals. The danger with infrared is that it can cause you to go blind, but you wouldn't even know it because your eyes can't see it. To get rid of this nasty infrared they have a filter that blocks all of it, but transmits the green light. By now, our nice straight light beam has gotten all messed up from going through all those materials, so another lens is used to straighten it out again.

If you check out the video on the site where it shows the laser burning paper (haha, I just spent so much time watching those videos) you'll notice that the laser is held very close to the paper. The hole it makes is the size of the laser beam at that distance from the output. At farther distances the beam spreads out a bit. Now, judging from the size of that hole, that's pretty small. Realistically, I don't think a lens will be able to focus that beam down too much more. I can't say for sure, but that's just my opinion. It looks pretty close to the minimum spot size.

Board of Command
Tue, 01-10-2006, 01:17 AM
Green light? Why not blue light or is that a little too close to UV for comfort?

KitKat
Tue, 01-10-2006, 10:17 AM
Well, blue light is quite possible although you'd have to use different crystals to produce it. The problem with blue light is actually with our eyes. We see green light the best, because it's right in the middle of our visible range. Blue light is rather near the edge. For a blue laser and a green laser of the same power and intensity, we will percieve the green one to be 3 times brighter (I think 3, but it might be as high as 10....I can't remember the actual value, so don't quote me on this). So to have an equivalently 'bright' laser, you need to use three times the power. This may be one reason why they don't offer blue lasers on their site.

Probably the biggest reason though is cost. The crystals you need to create blue light are super expensive. Check out this site (http://safeco2.home.att.net/laser.htm) which gives an estimate for blue laser pointers at $2000 minimum cost.

ChaosK
Tue, 01-10-2006, 05:42 PM
green because green is in the middle of our eye's visible color spectrum, where as blue is close to the end.

but now i ask, why red? though red is a big part of the color spectrum, its still at the edge, so why make red?

KitKat
Tue, 01-10-2006, 06:12 PM
That's a good question with a relatively simple answer. Yes, red is on the other end of the spectrum, but you can still see red better than blue. Also, red lasers happen to be extremely cheap and easy to make. That's why you can get red laser pointers at the dollar store these days. Remember all the crystals we had to deal with in the green laser? You can actually produce visible red light directly from a diode, so you can bypass all of those other steps. These lasers are made to be quite low power, usually only a few milliwatts so that anyone can use them and they can be sold anywhere. This has led to red lasers being extremely cheap and available.

ChaosK
Tue, 01-10-2006, 07:58 PM
oh, well okay that solves that. and of course nobody wants to see orange or yellow lasers flying around... i want the phoenix!

Board of Command
Tue, 01-10-2006, 08:26 PM
So green being near the middle of the spectrum makes it the most visible color. Well that answers a lot of my life's questions...

kaosoner
Fri, 01-13-2006, 11:13 PM
that shit is awesome!!!!! half of the ppl here said that kids dont need these right?... HOW ARE THEY GOING TO GET THEM WHEN THEY COST 200.00 U.S DOLLARS...... so we dont have to worry about dumbshit kids shootin us in the eye...unless your like my brother who likes beat the hell out of ppl anyway he can......but anyway ...who wants to point at a star in space (excluding astronomy ppl)......i want to test one of these, but i dont gots 200.00 dollars.....and that means it will replace my lighters and matches if i manage to get one.

Assertn
Sat, 01-14-2006, 04:24 AM
Originally posted by: BOARD_of_command
So green being near the middle of the spectrum makes it the most visible color. Well that answers a lot of my life's questions...

Is that what it said? Considering how small the range of visible light occupies with respect to the spectrum, I'd imagine that a shift from one color to the next would be very minute.

Kraco
Sat, 01-14-2006, 07:03 AM
Originally posted by: AssertnFailure
Is that what it said? Considering how small the range of visible light occupies with respect to the spectrum, I'd imagine that a shift from one color to the next would be very minute.

Colour vision is a bit complicated issue. And if you watch the laser in the dark, you have to add the effect of the night vision. If you have a look at this picture (http://webvision.med.utah.edu/imageswv/spectra.jpeg) (I don't want to leech it, so click the link), you will notice two things: The colour we perceive as pure red has a disadvantage of being somewhat far from the absorption maximums of the different types of cone cells we have (used to perceive coloured light). And it's also easy to see why green is seen so strongly, like KitKat said. It's not only absorbed by the green cone cells, but by the red as well, and strongly, generating a high signal.

The picture also shows the absorption spectrum of the rod cells, used solely in night vision, and as you can see, it doesn't really absorb red that well. However, it's right there for green light. Well, of course this also explains why red light doesn't impair your night vision...

KitKat
Sat, 01-14-2006, 11:24 AM
Assertn, you're absolutely right that visible light is only a miniscule portion of the electromagnetic spectrum, but as Kraco so nicely demonstrated above, our perception of visible light depends on how well our eyes absorb it. Green just happens to be in the middle of the portion that is visible to us, and we can distinguish many subtle colour variations that represent small wavelength changes.

ChaosK
Sat, 01-14-2006, 02:10 PM
Originally posted by: KitKat
Assertn, you're absolutely right that visible light is only a miniscule portion of the electromagnetic spectrum, but as Kraco so nicely demonstrated above, our perception of visible light depends on how well our eyes absorb it. Green just happens to be in the middle of the portion that is visible to us, and we can distinguish many subtle colour variations that represent small wavelength changes.


jesus i feel like i'm in 8th grade again.

KitKat
Sat, 01-14-2006, 07:17 PM
Originally posted by: Chaoskiddo
jesus i feel like i'm in 8th grade again.
Don't disrespect optics! Or else you shall incur the wrath of KitKat and her arsenal of nuclear-powered quantum laser blasters!!! i/expressions/face-icon-small-frown.gif

Board of Command
Sat, 01-14-2006, 08:18 PM
Yes the visible spectrum is only a few percent of the entire electromagnetic spectrum, but since our eyes are only able to perceive the visible spectrum, that is the entire spectrum to our eyes. Although going from green to red on the electromagnetic spectrum is an omissible change, it makes a whole world of difference on the visible spectrum.

ChaosK
Sun, 01-15-2006, 12:17 AM
Originally posted by: KitKat


Originally posted by: Chaoskiddo
jesus i feel like i'm in 8th grade again.
Don't disrespect optics! Or else you shall incur the wrath of KitKat and her arsenal of nuclear-powered quantum laser blasters!!!


no i meant the talking about electromagnetic spectrum and the visible spectrum. its earth science all over.