how big a magnifying glass would it take

[lesodell]

how big a magnifying glass would it take to make as much heat as a 1000mW laser ? anyone ever seen a chart ?

and when using a coherent laser checker should the beam be focused to its smallest point to check its power ? thanks ++

 

[RA_pierce]

The power of the sun light reaching the surface of the Earth is around 1.2kW/m^2.

That is, every square meter of the ground gets about 1.2kW of light from the Sun. Using this, it should not be too hard to solve your problem.

 

[Gryphon]

Ive got a large lens about 1 foot square, on a nice sunny day it will set wood on fire in just a couple seconds, there is a load of power in sunlight.

 

[RA_pierce]

Oh - one more thing.
Do not focus a beam of sunlight onto your Coherent laser checker.
You will destroy it. Not to mention... don't those things have different calibration for different wavelengths?
Sunlight consists of light from UVA to infrared.

 

[qumefox]

WOuld take a lens with the area of 8.333333 cm²

 

[bootleg2go]

WOuld take a lens with the area of 8.333333 cm²

And since area=Pi*r^2, that would mean a round lens with a diameter of 32.57mm (or about 1.25 inches across).

 

[DrSid]

It would mean you need protective glasses for that ! Dangerous toys !

 

[lesodell]

thanks for the reply's . boy we have all this fancy tech and it is nothing compared to nature

 

[mfo]

It would mean you need protective glasses for that ! Dangerous toys !

Welding glasses would suffice.

thanks for the reply's . boy we have all this fancy tech and it is nothing compared to nature

This.

 

[Braddubya]

In actual practice there a lot of variables that would come into play but as you can see it dosnt take much, but then again I think many laser enthusiasts dont appreciate lasers for their raw power as much as the amazing physics involved. Sunlight, even focused , is much different than a laser.

 

[DrSid]

And you can't get sunlight in handheld form and many nice colors. But for burning it would really cool if you invest same amount of money as you do into laser.

Btw. what about solar pumping ? I tried with green DPSS module .. and it totally does not work. I would understand that specific wavelength range is needed for pumping, but IMHO sunlight should contain that near IR which is normally used. Must it be pumped by laser ? Is it polarization problem ?

 

[Braddubya]

And you can't get sunlight in handheld form and many nice colors. But for burning it would really cool if you invest same amount of money as you do into laser.

Btw. what about solar pumping ? I tried with green DPSS module .. and it totally does not work. I would understand that specific wavelength range is needed for pumping, but IMHO sunlight should contain that near IR which is normally used. Must it be pumped by laser ? Is it polarization problem ?

I could be wrong but even if its pure IR it shouldnt work unless its pulsed. From my understanding photos will not be released correctly with a constant energy source.

 

[mfo]

Btw. what about solar pumping ? I tried with green DPSS module .. and it totally does not work. I would understand that specific wavelength range is needed for pumping, but IMHO sunlight should contain that near IR which is normally used. Must it be pumped by laser ? Is it polarization problem ?

I know polarization is a must, but I'm not sure if being pumped by a laser is a must.

 

[DrSid]

I mean most solid state lasers are pumped by simple fluorescent tubes right ?

But I guess I found the problem .. the actual IR power may be pretty low. I pumped it with like 1-2W (with lens) .. but that is whole spectrum .. IR only would be under 5% of that. And that is not impressive for pumping.

As for polarization I think normal IR diodes are not pulsed.

As for polarization, at least with DPSS greens the crystal must be aligned with polarization of pump diode, that is sure thing.

 

[Asherz]

I mean most solid state lasers are pumped by simple fluorescent tubes right ?.

If you mean DPSS (Diode pumped Solid State) laser then no, they're pumped by 808nm IR diodes.

 

[DrSid]

If you mean DPSS (Diode pumped Solid State) laser then no, they're pumped by 808nm IR diodes.

No I mean common solid state lasers. Actually it is true for gas lasers too right ?