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sanwu laser beam expander

QiQi

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Hello
i wanted to ask if some of you guys have experience with the sanwu laser expander
https://www.sanwulasers.org/product/x3beamexpander

it expands the beam 3 times with it
but does this also mean that the beam will be watered down (more transparent) ?
so when looking at the side of the beam it will be not so visible anymore?

also does the expander works on the sanwu laser with the head caps attached?

https://www.sanwulasers.org/product/attackcap
(i would really want to know if this would attach to the crown head cap)

thank you in advance
 
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paul1598419

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The purpose of a beam expander is to decrease the divergence of the beam down field. The visibility of the beam will depend on its wavelength and power. Green is the most visible mW for mW, so you will see the beam of a green laser of equal power better than any red or blue wavelengths. Also, the greater the optical power your laser has the more visible it will be when compared to the same wavelength at a lower power. Hope this answers your questions.
 
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QiQi

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Hi
So the beam expander Will not decrease beam visibility? I thought by expanding your beam it gets watered down because your beam is not as focused anymore without the beam expander
 

Gazen

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You will decrease power density since you are increasing the area the beam is spread across. On top of this, there will be some power loss due to the lenses. But, at a long distance since the be will decrease divergence the power density will be greater.
 

hakzaw1

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I also needed help wrapping my head around BEs.
did you search? ; how beam expanders work

https://laserpointerforums.com/search.php?searchid=2054258

Think-- a BE extends the 'sweet spot' (or pop matches and light balloons from a longer distance). You should use the google search I hope you see at the bottom of every LPF page- due to my needing dial=up modem (ATM no 'affordable option') I do not get the search to load (fine at the 'office' tho )
also BEs
They protect you lasers' lens.
and many do not remove their BEs coz it was a 'beeotch' getting the adaptor and focus rings in the best spot.--

be very aware:
the 'mechanical advantage ' due to extreme diameter sizes (differences) can easily get your B.E. TOO tight to reverse easily (unscrew) later.

-- IF that does happen take extra care to NOT scratch your laser or your BE's barrel using vice grips etc. rubber or leather to avoid scratches. JETLASERS cannot replace/refund scratched Beam Expanders/.

JL also has a YTube vid on their BE.

best wishes--Hak
 
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Gazen

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I also needed help wrapping my head around BEs.
did you search? ; how beam expanders work

https://laserpointerforums.com/search.php?searchid=2054258

Think-- a BE extends the 'sweet spot' (or pop matches and light balloons from a longer distance). You should use the google search I hope you see at the bottom of every LPF page- due to my needing dial=up modem (ATM no 'affordable option') I do not get the search to load (fine at the 'office' tho )
also BEs
They protect you lasers' lens.
and many do not remove their BEs coz it was a 'beeotch' getting the adaptor and focus rings in the best spot.--

be very aware:
the 'mechanical advantage ' due to extreme diameter sizes (differences) can easily get your B.E. TOO tight to reverse easily (unscrew) later.

-- IF that does happen take extra care to NOT scratch your laser or your BE's barrel using vice grips etc. rubber or leather to avoid scratches. JETLASERS cannot replace/refund scratched Beam Expanders/.

JL also has a YTube vid on their BE.

best wishes--Hak
I know that you are asking about the sanwu beam expander, but jetlasers(the one hackzaw was talking about) also has a beam expander that is 10X rather than 3.
 
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Alaskan

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There are a few members who have posted about that Sanwu BE here, it's actually 3.3 expansion, it's about as inexpensive as you can buy, but not bad at all.

What is your interest in having a beam expander? To keep the beam tighter as it travels away (reduced divergence) ? I guess so, other than making the beam fatter or wider, that's what they are for but some can extend the focal point for burning, if there is enough focal adjustment, but normally they have limited adjustment range to be able to do so, as they are primarily intended to expand the beam and collimate to infinity focus, not for refocus down to a spot.

The Sanwu 3X has some adjustment in case the input isn't perfectly collimated, as well as to accommodate a range of wavelengths for adjustment to "infinity" focus which just means to make the light waves exit more or less parallel, in the distance they will creep wider anyway as they slowly diverge, but the more the beamwidth is expanded (i.e. 5, 8, 10, 20X etc.), the slower that will occur. Some beam expanders are fixed focus, you can't adjust them at all which means the input must already be at infinity as well as a limited range of wavelengths which can be used with it. In that case, they are normally specified for a single wavelength, plus or minus some number of nanometers with a narrowband AR coating on the glass.

What do you mean if the end caps are attached? The members I remember seeing posts about that beam expander are RedCowboy and ArcticDude, perhaps one of them or another member who has used one will chime in. I will be buying a few soon myself for some hosts I had made which were machined to accept them.
 
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Gazen

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From XM360’s review I know that the attack caps have threading on the front to accept star caps, but I haven’t seen someone put a beam expander on top of one. From the video I believe it may be possible to thread the be on, but it will not be ideal.

Here’s the review

https://m.youtube.com/watch?v=UV9uo-RAazk&t=934s

He shows the attack heads in the beginning.
 
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paul1598419

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I wouldn't go by anything XM360 says. I've caught him giving terrible advice about lasers he knew nothing about. And all he had to do was ask, but instead he guessed. But, guessed wrong. See his review of Laserpointerstore's RGB laser. Just awful.
 

Encap

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I wouldn't go by anything XM360 says. I've caught him giving terrible advice about lasers he knew nothing about. And all he had to do was ask, but instead he guessed. But, guessed wrong. See his review of Laserpointerstore's RGB laser. Just awful.
Exactly.

QiQi: "does the expander works on the sanwu laser with the head caps attached?"
Common sense says what?
Email Sanwu and ask--simple enough?

From photo fromSanwu site-- if this is what you are talking it is very obvious the answer is ---no:

 
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steve001

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Hi
So the beam expander Will not decrease beam visibility? I thought by expanding your beam it gets watered down because your beam is not as focused anymore without the beam expander
To answer your question yes. How much less intense the beam appears depends mostly upon the initial milliwatt output and the wavelength and the expansion power of the beam expander.
 
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Alaskan

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If the beam is expanded, it will have less power density per square (what ever) diameter and will look what you describe as being watered down close up, but if you don't have a beam expander on that pointer, it's really going to get watered down quick in the distance as it expands so fast due to high divergence, I guess it just depends on which end you want the beam watered down.
 

QiQi

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To answer your question yes. How much less intense the beam appears depends mostly upon the initial milliwatt output and the wavelength and the expansion power of the beam expander.
it's going to be 1W 520nm, 4W 470nm and 1W 635nm
it's all above 1W so i hope the beam will still be "very" visible or at least i hope the 520nm will be

If the beam is expanded, it will have less power density per square (what ever) diameter and will look what you describe as being watered down close up, but if you don't have a beam expander on that pointer, it's really going to get watered down quick in the distance as it expands so fast due to high divergence, I guess it just depends on which end you want the beam watered down.
thank you
 
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Alaskan

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Look at my avatar where I'm pointing a huge laser pointer into the sky, that's 1.4 watts of 520 nm green expanded to about four inches.
 

RedCowboy

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The purpose of the beam expander is to reduce divergence and give you the ability to focus to a tighter spot at distance by expanding the beam to start with.

 




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