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Purple 405nm 1.6w or Green 525nm 1.2w (Sanwu Lasers)

RADU2975

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I looked on sanwu lasers at the new rangers series and can't decide witch one to by(the green option is 60 dollars more expensive),all I know is that the 405nm has a far more better divergence than the green one(I think that they are using an dpss diode) but the green one is far more vizible to the human eye (I'm planning to get one of it with the X3 beam expander and the 3 element lenses) .Any help?
Laser Rangers - Sanwu Lasers
 



paul1598419

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First of all there aren't any DPSS laser diodes. DPSS stands for "diode pumped solid state" and is actually a system containing solid crystals that shift the IR pump diode wavelength to a visible wavelength. That said, the 405nm ones are mostly single mode blueray diodes that have been greatly over-driven. That wavelength is so close to UV that they aren't very visible even at close too 1 watt. If you want a laser to burn with they are great. You can pop balloons at greater distances that many other laser diodes, but the green is by far more visible. I have a 520nm laser doing 1100 mW and a 532nm doing 1300 mW and they are extremely bright especially when compared to other wavelengths in blue or red.
 

Crackula

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First of all there aren't any DPSS laser diodes. DPSS stands for "diode pumped solid state" and is actually a system containing solid crystals that shift the IR pump diode wavelength to a visible wavelength. That said, the 405nm ones are mostly single mode blueray diodes that have been greatly over-driven. That wavelength is so close to UV that they aren't very visible even at close too 1 watt. If you want a laser to burn with they are great. You can pop balloons at greater distances that many other laser diodes, but the green is by far more visible. I have a 520nm laser doing 1100 mW and a 532nm doing 1300 mW and they are extremely bright especially when compared to other wavelengths in blue or red.
Paul what causes the 405nm to burn at greater distances?
 

GSS

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Basicly, the 405's we use now are single mode which have better divergance which leads to a tighter spot at distance.
Plus the 405 WL has it's benefit's. I can't answer this point, but others will chime in..
Paul is usually off at this time..so it's just the basics.
 

Crackula

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Basicly, the 405's we use now are single mode which have better divergance which leads to a tighter spot at distance.
Plus the 405 WL has it's benefit's. I can't answer this point, but others will chime in..
Paul is usually off at this time..so it's just the basics.
Thank you for the reply GSS. I figured there is a difference in divergence, but I'm curious to know if wavelength makes a difference with powers being equal.
 

tmoney321

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Thank you for the reply GSS. I figured there is a difference in divergence, but I'm curious to know if wavelength makes a difference with powers being equal.
A photons wavelength is related to its energy. So yes, since lower wavelength photons have higher intrinsic energy. Power density and divergence can be taken into account too, hence the tighter spot mentioned. Another variable is the characteristics of the object being burned - how well it absorbs/reflects a given wavelength. This is why lower power lasers can have trouble with matches that are lighter colored.

Here is a portion of a poster that illustrates the energy(eV)/wavelength(m)/frequency(Hz) relationships
Capture.PNG
 
Last edited:

paul1598419

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Yes, they are all single mode laser diodes, so that is why they give better divergence specs. Power is power, so any 1 watt laser will burn as well as the next as long as your target absorbs both equally.
 




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