what color of laser is best for burning

[Burnsy]

This is nonsense. We measure lasers in mW .. which is generally the burning power. Red 200mW will burn perfectly same blue 200mW, at least black targets. The fact that blue photons have higher energy means just that blue laser will need less photons to achieve the same power. It also means blue laser will take more power to generate these photons.

True all 200mW will do the same... BUT:

405nm is the best burner! Simply because the 12x diode has big power AND stay in a very nice TEM00 (or nearly) dot.

If I compare my 405 600mW with my 1600mW 445 for burning then the 405 wins by far. It's just so easier to collimate it to a nice small dot while on the 445nm the bar shaped dot burns only very hard at a short distance and even then it's more difficult to collimate it.


Of course a nice DPSS dot like from a 532nm with adjustable focus will also do perfectly but 600mW of 532 is a "bit" more expensive than 405nm.

 

[Arayan]

True all 200mW will do the same... BUT:

405nm is the best burner! Simply because the 12x diode has big power AND stay in a very nice TEM00 (or nearly) dot.

If I compare my 405 600mW with my 1600mW 445 for burning then the 405 wins by far. It's just so easier to collimate it to a nice small dot while on the 445nm the bar shaped dot burns only very hard at a short distance and even then it's more difficult to collimate it.


Of course a nice DPSS dot like from a 532nm with adjustable focus will also do perfectly but 600mW of 532 is a "bit" more expensive than 405nm.

Correct

practically the visible laser better (and cheaper) for burning is a 445 nm 1W or more, with a focusing lens...

 

[Ash]

For the same power (~100mW) the lower the wavelength the better for burning because there is a higher power-density at the focused spot. (more photons can get focused into a smaller spot)
Burning: 380nm>405nm>445nm>532nm>589nm>635nm>660nm>808nm
Of course a 20W CO2 laser (10,600nm) will burn better than a 2W diode laser (445nm) due to the large amount of power at the focal point.

 

[Arayan]

For the same power (~100mW) the lower the wavelength the better for burning because there is a higher power-density at the focused spot. (more photons can get focused into a smaller spot)
Burning: 380nm>405nm>445nm>532nm>589nm>635nm>660nm>808nm
Of course a 20W CO2 laser (10,600nm) will burn better than a 2W diode laser (445nm) due to the large amount of power at the focal point.

It also depends on the absorption of different materials. For example most organics don't absorb at "low" wavelengths very well, while they absorb at 10.6 microns light, so non-metal processing is generally a CO2 application...