Bluray Laser vs Green Laser?

[HotDog-Cart]

Hey guys. I have a science question, that the internet doesnt seem to awnser. I looked at the wikipedia on laser pointers too, but no avail. (These are for school. Help me out )

1) Are bluray lasers STRONGER than green lasers? (Stronger meaning put out more heat, stronger beam, able to pop balloons and do more damage faster?)

2) Is more nm output better?

3) Is more mW output better?

4)Whats the mW output of bluray lasers? (Wikipedia mentions the mW output for red, green and yellow, but doesnt say anything about bluray lasers.)

5) Last question: If I took multiple lasers (such as 4 green ones for example), and aimed all of them at one spot on an object (all of the lasers aiming and focusing at this one spot in particular), would the beam be stronger than if I just aimed 1 laser poined at that spot?

[Triton]

nm is nanometers, or more specifically the wavelength of the light that is emitted from the laser. mw is the "power" output of the laser, the higher the mW the more powerful the laser. i dont remember off the top of my head but bluray lasers are pretty powerful, at least comparable to green lasers. and to answer your last question yes, if you focus 4 lasers at the same point that point would be receiving 4 times the energy input than if you pointed one laser at it. I know there have been posts on hackaday about bluray lasers and the like so you might want to search on there for more specific information!

[vskid]

Hey guys. I have a science question, that the internet doesnt seem to awnser. I looked at the wikipedia on laser pointers too, but no avail. (These are for school. Help me out )
1) Are bluray lasers STRONGER than green lasers? (Stronger meaning put out more heat, stronger beam, able to pop balloons and do more damage faster?)
2) Is more nm output better?
3) Is more mW output better?
4)Whats the mW output of bluray lasers? (Wikipedia mentions the mW output for red, green and yellow, but doesnt say anything about bluray lasers.)
5) Last question: If I took multiple lasers (such as 4 green ones for example), and aimed all of them at one spot on an object (all of the lasers aiming and focusing at this one spot in particular), would the beam be stronger than if I just aimed 1 laser poined at that spot?

1) Depends on the laser, not the color. Bluray lasers are probably more powerful than most pocket size green lasers. The useful power also depends on the color of what the light is hitting (a green laser will heat a red or black object faster than a green or white object).
2) Not necessarily. Wavelength (measured in meters, visible light is in the nanometer range) determines the type/color of light. Blue light will always have the same wavelength (with some variation for different shades). If you increase the wavelength, it'll be green, decrease it, it'll be purple. DVD players use a red laser, bluray uses a blue laser. The shorter wavelength of the blue light allows the data to be packed closer together, thus higher storage capacity.
3) Watts are the actual measure of power. More watts=more power.
4) A certain color is not automatically more or less powerful than another. I think it might be easier or more efficient to get more power using certain colors, but I don't know for sure.
5) Yes.

[HotDog-Cart]

Whats the typical mW output of a bluray laser? I know the wikipedia has all the information for green lasers, but doesnt even say anything about the power output. Thanks for all the awnsers guys, I just need that last question awnsered. My teachers hounding me.

[vskid]

It looks like about 10mw (thats the average from what I can find). I think the 150-200mw ones are from bluray burners.

[HotDog-Cart]

10mw? And how much mw is a green laser usually? (I'd rather not go from wikipedia. I'd use google, but I'm hindered by insanely slow internet.)

And if the green laser is higher than 10mw, that means it would be stronger than a bluray laser right? (excl. the bluray lasers from burners.)

[vskid]

And if the green laser is higher than 10mw, that means it would be stronger than a bluray laser right? (excl. the bluray lasers from burners.)

Yep, if that 10mw number is correct (I'm not 100% sure). In the US, I think 5mw is the most powerful handheld laser you can legally buy. I don't think Canada has any laws about laser power, but I would expect most to be under 5mw just to be universally legal. You could buy high power lasers from China, but I've heard their power ratings are several times higher than their true output.
I think the craze about green lasers a few years ago was caused by green light being easier to see. A 5mw green laser appears brighter than a 5mw red laser.
What are you trying to do?

[HotDog-Cart]

Its for a small science project in class. The teacher is going to buy a laser, for the class to do some like stuff with. (Like popping balloons with, light matches, and such.).

He just wanted me to figure out which laser would be the best to use for that, and I would get bonus marks. (By best, I presume he means strongest. I'm unsure if price matters. Is a green 5mw laser stronger than a red 5mw laser? If not, then he could cheap out and buy a red one, as green lasers are more expensive)

Canada doesnt have any laws about lasers but heres the problem: If the teacher buys one from china, wont it come through the states before it enters canada? If so, that means it must be under 5mw, because of US laws right? (Anything over that, would be illegal.) Or is there someway that he could buy a 10mw laser and have it imported to canada without going through the states? (Like I said, if its like 10mw, we cant have it go through the states to get here in Canada, because of the fact that it'd be illegal.)

Mind you, this could be nonsense because I totally forget the shipping process, when someone in Canada orders from china. I swear it goes from China to the States then to Canada, but I could be wrong...

[vskid]

I'm not sure if it can do the job, but I would try to keep under 5mw, just for safety. 5mw is just weak enough that you can blink in time to not receive any permanent eye damage. Your school might not be happy having a laser capable of blinding students within seconds.

[HotDog-Cart]

We need it to do the job unfortunately. The teacher is going to be handling the laser at all times.
Power > Safety. haha

Whats stronger? A 5mw green laser or a 5mw blu Or a 5mw red? (Or does color not matter. They'd all be 5mw, therefor all the same strength).

I personally want to see the strongest that I could recommend my teacher for the fairest price. And yes, it will have to be able to do the job. haha if he can get a 10mw, then bam. That'd be sweet.

I do see where your coming from with the safety precautions though.

[timmeh87]

Man if I didn't know better, Id say it sounds like you guys got this far without doing a proper google search...

According to wikipedia, DVD burners have lasers on the order of 250mW. Im pretty sure its a red (650nm) laser in that case. Presumably, Blu-ray lasers are also pretty powerful, but they are obviously more expensive. They use a violet wavelength (405nm), without any frequency doubling crystal thingy. If you are taking apart a PS3 though, I dont think the laser is going to be as powerful as a DVD burner. Burners have more powerful lasers, obviously.

Handheld lasers are available in powers of much grater than 250mW, and a significant portion of them are green. They use a different colored light sources, and some kind of fancy crystal which changes the frequency of light. generally they cost about 10 to 20 times more than a dvd burner.

http://www.highlasers.com/250mW-Green-Lasers.html" onclick="window.open(this.href);return false;

If you dont need green, red is cheaper

http://www.highlasers.com/Red-Laser-Pointers.html" onclick="window.open(this.href);return false;

Also, you might want to look for spare laser projector parts on ebay, you can probably find some >1W lasers. Really, its just a matter of the price you are willing to pay.

One thing I would like to point out though, is that the spot size on "pen" lasers is much larger than the spot size on a dvd/blu-ray laser, so the power-per-sqaure-meter would probably be higher in the case of aDVD burner, Ie a smaller, hotter spot.

However, it is entirely possible that a laser from a burner will not focus very far away. I mean its designed to focus to a 500nm-1000nm dot about 5mm away from itself under normal operation...

If I were you, Id hit youtube

http://www.youtube.com/watch?v=4z9Zj0O0-bk" onclick="window.open(this.href);return false;

etc....