Lasers: Geek Discussion

[Tac]

What is it that gives a laser the ability to 'punch' and burn through objects?

Comparing a laser pointer to an industrial laser for example....

both emit coherent light.. but from my understanding the industrial one just pumps more energy into the beam.

But... what I dont get is how that energy travels in the beam. Does it mean that the stronger beam just carries more photons?

Or is it the wavelength the photons travel on? Or both?


(yes im the kind of person that wants to know how to make a laser pointer burn through paper )

[Nilsen]

No idea because lasers are just capitalist imagination from tv


j/k.. i think its has something to do with wavelenghts and energy. Atleast they say that a lasersight for a gun is on a wavelength that does not damage the eyes and so forth so that is one expression they use when talking about "lasers". Other wavelenghts are use to fix eyes, but that may just be a different energy ammout used to burn stuff in the eye.


beyond that i dont have a clue about these sci-fi stuff.

[lukster]

This is pretty good: http://en.wikipedia.org/wiki/Laser

Based on my simple (and likely incorrect) understanding of lasers, any object that intercepts and does not reflect the laser abosrbs the photons and their energy resulting in heat which might melt the object if the energy is sufficient.

[Debonair]

high energy photos & lots of them do the job.
that why i always bet on the purple light sabre guy over the red one

[CyranoAH]

Originally posted by Tac
What is it that gives a laser the ability to 'punch' and burn through objects?

Comparing a laser pointer to an industrial laser for example....

both emit coherent light.. but from my understanding the industrial one just pumps more energy into the beam.

But... what I dont get is how that energy travels in the beam. Does it mean that the stronger beam just carries more photons?

Or is it the wavelength the photons travel on? Or both?


(yes im the kind of person that wants to know how to make a laser pointer burn through paper )

Let me try to explain... I'm an engineer, not a physicist, so if there's one present, feel free to correct me

Think of a Laser as thousands of small emitters sending a coherent beam. If you want more power, you need more emitters.

If a photon is emitted when you get a material's electrons to rise to another energy level and then back to its original state, you need more electrons to do just that if you want more output power.

In a 1W laser, you get a lot more power per surface unit than in a 5mW one because the material is able to send more photons in the beam that results from the coherent emission.

Daniel

[WhiteHawk]

I think its the same principle as using a magnifying glass to burn a hole in a piece of paper.  Super concentrated light=energy.