whats the most powerful wavelength?

[GooeyGus]

1W is 1W is 1W.... but if we're talking about cutting then I think Tocket's answer is dead on. It all depends on the material

If you have 1W of 405 and 1W of 650, then you could achieve higher energy density with the 405 because it can be focused smaller, but as we know the overall power is still the same.

[thesk8nmidget]

thanks everyone this all makes sense and i now have some more info to refer to

[trwalters001]

As far as cutting is concerned, the material being cut determines what wavelength is to be used.
NdYAG (1.06u) is great for aluminum, for instance. CO2 (10.6u) has a real hard time with it unless you get into fairly high power (what Tocket said).

Tim

[The_Doctor]

Thread resurrection time.
Only one person said that there is more energy per photon in shorter wavelengths. Now as energy relates directly to power vs time, does this mean that fewer photons per second are emitted for 1W of blue light than 1W of red light? Even assuming this is true, and that some sheet of substance were not fussy about absorption wavelengths, wouldn't the ability of shortwave light to smack electrons out of its atoms count for more than the smaller diffraction limited spot? As red is (roughly) twice the wavelength of violet, I image the difference in spot area theoretically reaches about four-fold power density for violet compared to red, but I don't know whether the ability to cut black tape or carbon paper would be fourfold better with violet. I suspect more, and I'm not sure how much difference if any would be due to the greater energy per photon...

Can anyone spare me a dry and boring Google search, followed by links I'd probably have to pay to read anyway, and which would go straight over my head if I did? I bet this stuff has been quantified somehow..

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As far as cutting is concerned, the material being cut determines what wavelength is to be used.
NdYAG (1.06u) is great for aluminum, for instance. CO2 (10.6u) has a real hard time with it unless you get into fairly high power (what Tocket said).

And you can reverse that selection for acrylic.

[JD3]

I used a 10 watt 1064nm laser for etching tools and dog tags in the military. It had a rather small focal point. You could set it it one spot and it would never puncture a dog tag. BUT if you put it on wood it would quickly dig into the wood before it came out of its focal point.

(It was also fun to use it to remove the reflective backing on a mirror. Just load up in image in the CAD program and focus on the back pane of glass. Looked like the laser was just wiping off the reflective material)

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^ this was probably a 1mm beam at its focal point

[kecked]

E=HC/Wavelength where H is planks constant and C is the speed of light Thus energy is inversely proportional to the wavelength . The shorter the wavelength the higher the energy in a photon packet. That means the lower the nm number the more energy. Red has less than violet. That is an absolute but doesn't answer the issue of "burning". That is based on the ability of a an object to absorb the energy. This is why CO2 lasers in the far infrared can burn better then 660nm lasers as an example. There is an absorption band in this region that includes the Hydroxyl group and water group. This is also why a microwave oven with even lower energy can burn by causing the water molecules to vibrate translationally and hence move faster which his the definition of heat. Didn't want to get more technical than this but happy to if you really want it but expect a few pages. BTW Einstein developed the photoelectric effect which is the above statement "sort of" before he was famous for the relativity stuff. That is why we have solar cells. higher energy than a threshold can knock free electrons and cause an electric flow.

The above post also point out that the shorter the wavelength the smaller the spot size(that's why they can pack more electronics in a 37nm pattern than a 22nm pattern) can be made and hence the larger the amount of energy that can be applied to a spot. What I state is physics. That is a practical matter of focus. Two beams of the same intensity erg/cm2 will be as I state the shorter wavelength will need less photons to achieve the same energy density.

1 pound of feathers is the same as one pound of lead The lead takes up less space because it is more dense. Take that analogy over to energy and you have the idea though not for the same reason.

[Laserman532]

what is truly weird is back in 2009 when this thread was started...i still had hair