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Newbie here  - converging beams inc. power?

photon

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Hi,

I'm a newbie here - have yet to build my first laser but have a few questions.

If you have two or more converging beams, is the power output the same as one diode or the sum of all diodes?

In other words, if you have one beam at 50mw, another focused at the same spot at 50mw, is the Total Power Output 100mw or 50mw?

Also, can a laser beam be made to act as an electrical conduit under certain circumstances.

Thanks

photon
 





Re: Newbie here  - converging beams inc. power?

The total power is equal to all the parts :-) 2 times 50mw = 100mw (in MOST circumstances)
 
Re: Newbie here  - converging beams inc. power?

yep greg is right, and as for the electrical conduit, what do you mean by that? sorry if it is really obvious, but i am still young :D if you mean can it conduct electricity? yes lasers can be a path for electricity, BUT you need multi watts for this to happen, since it has to ionize the air.
 
Re: Newbie here  - converging beams inc. power?

oh and welcome to the forum! ;)
 
Re: Newbie here  - converging beams inc. powe

things said:
yep greg is right, and as for the electrical conduit, what do you mean by that? sorry if it is really obvious, but i am still young :D if you mean can it conduct electricity? yes lasers can be a path for electricity, BUT you need multi watts for this to happen, since it has to ionize the air.


Try tens of killowatts. Something not quite attainable for the average hobbyist. Sending power over the beam would defeat the purpose, the electrical contact at the other end would be toast.
 
Re: Newbie here  - converging beams inc. power?

Well, if you mean combining beams, unfortunately that's not as simple as we'd like to hope. As for focusing multiple beams to the same spot, its a bit of a toss up. Destructive interference may mean that its not a simple addition problem, but past that I really don't know.

Under the right circumstances, a laser can ionize air like if you cause dielectric breakdown with a high voltage supply (like a spark plug, tesla coil, neon sign, etc). I don't know any links at the moment, but if you search around there are some articles where this has been used to draw lightning, or to shoot electricity across a hall. However, as said above, this isn't really a hobbyist pursuit.

The high amount of power needed to form a conduit of any reasonable length would entail a pulsed laser, peaking with an insane number of watts, and costing a huge number of $$$s
 
Re: Newbie here  - converging beams inc. powe

that's odd - i read somewhere that they were trying out getting lasers to conduct electricity to use as a long range non-lethal taser variant. however, if the laser itself would burn a hole through the target it seems a bit pointless to use as a taser... lol
 
Re: Newbie here  - converging beams inc. powe

If you have a HV source, a fun experiment to try is to charge a cap and set a spark gap so that it just won't fire. Then hit the space in the gap with a laser (even just .2 Watts) if you keep playing with it you can get it to fire. I assume the laser partially ionizes the air thereby reducing the dielectric strength and allowing the spark gap to fire.
Fun stuff and a very good question. [smiley=thumbsup.gif]
 
Re: Newbie here  - converging beams inc. powe

a_pyro_is said:
If you have a HV source, a fun experiment to try is to charge a cap and set a spark gap so that it just won't fire. Then hit the space in the gap with a laser (even just .2 Watts) if you keep playing with it you can get it to fire. I assume the laser partially ionizes the air thereby reducing the dielectric strength and allowing the spark gap to fire.
Fun stuff and a very good question. [smiley=thumbsup.gif]

The laser is giving you photoelectrons (the thing Einstein got the Nobel prize for) off of the metal which are then accelerated by the field leading to an avalanche and full breakdown of the air.

People have made things called laser wakefield accelerators that can make like GigaAmp currents by accelerating bunches of electrons to highly relativistic velocities with ultrahigh intensity lasers. That is the only "electric transmission" that I know of along a beam.
 
Re: Newbie here  - converging beams inc. powe

So, at a lower [ch955] (like a BluRay...er...um...I mean Mary :D) would this be much easier to do? That is, with a higher frequency and therefore higher energy quanta, more metals would exhibit a photoelectric effect. How about using an older camera flash emitting UV to cause the spark gap to fire?

Does anyone have a Mary, a greenie, a red, an IR, a HV source, a dark room to work in, and the desire to experiment?

Edited because I forgot to mention how amazing the vast sum of knowledge is on this forum.

You people are Amazing in your vast sum of knowledge!
 
Re: Newbie here  - converging beams inc. power?

Man, I have to add this! I have built a quarter shrinker, and a can crusher, wouldnt it be awesome to trigger the switch with a laser pulse! I wonder how hard it would be to do. :D

Max
 
Re: Newbie here  - converging beams inc. powe

Sorry to go off thread again, but how far down have you shrunk a quarter? If you say "all the way down to an eighth" I'll be impressed. :D ;D
 
Re: Newbie here  - converging beams inc. power?

My girlfriend can shrink DOLLARS way ,way smaller than that. Impressed?
 
Re: Newbie here  - converging beams inc. powe

tatman said:
My girlfriend can shrink DOLLARS way ,way smaller than that. Impressed?

Now THAT is a cruel truth ;D

Nice topic and great discussion... I do remember seeing a video of a laser conducting electricity as a form of security thing for a door somewhere for the gov't... does anyone remember where that was?

--DDL
 


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