looking for beam expander for 3.5W 445

[sss]

most of the beam expanders are rated at 500mW/cm2 , what does it mean?

also , any drawbacks using expander with multimode diodes ?
any other ways to lower the beam divergence?

thanks

 

[IsaacT]

That means that per square centimeter, 500mW of power can be passed without damage to the Deam Expander. Or atleast, that is how I interpret it.

 

[Blord]

Be ware that the beamexpander will also enhance the beam profile of the multimode 445nm laser. The small bar shaped dot will be much larger on short distance.

 

[sss]

That means that per square centimeter, 500mW of power can be passed without damage to the Deam Expander. Or atleast, that is how I interpret it.

so no way to lase 3.5w through it , unless i can make the beam spread over more then 2cm^2

 

[AJ Pierson]

most of the beam expanders are rated at 500mW/cm2 , what does it mean?

also , any drawbacks using expander with multimode diodes ?
any other ways to lower the beam divergence?

thanks

Hi SSS,

That max. power rating sounds a bit low to me. Can you give us some links to the products and specs that you're talking about?:thinking:

Regarding their use with multimode beams, I don't see any issues as long as your beam dimensions don't exceed the maximum input beam diameter of the expander.

 

[sss]

I contacted thorlabs, their expanders are rated at 100w/cm^2.thats still not enough if i lase 2mm^2 beam through it.

 

[EpicHam]

I don't think a beam expander will do you much good with a 445nm tho .
In the effects of Rayleigh scattering , the perceived beam size is big enough already .

What are you trying to achieve with a beam expander on a 445nm anyway?
What is the diode's divergence? Beam diameter?
Need some specs brah

 

[sss]

I don't think a beam expander will do you much good with a 445nm tho .
In the effects of Rayleigh scattering , the perceived beam size is big enough already .

What are you trying to achieve with a beam expander on a 445nm anyway?
What is the diode's divergence? Beam diameter?
Need some specs brah

I wrote in first post - trying to lower beam divergence. Expander makes the beam "bigger", but also reduces divergence, so at long distance, the dot will be smaller with expander used.

 

[EpicHam]

I wrote in first post - trying to lower beam divergence. Expander makes the beam "bigger", but also reduces divergence, so at long distance, the dot will be smaller with expander used.

I know what a Beam expander does , what I am saying is ... would it be better if you use it on other lasers instead??

Cos a 445nm wouldn't be making the most out of the expansion ratio