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New! Sharp Diodes 1W 520nm & 5W 455nm & +2W 638nm




CDBEAM777

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Hmmmm...I think the FAC corrected Sharp is on the left....because....525nm would have more a yellow tint...and the left unit looks to have a yellow tint....IMNSHO...also...the beam on the left appears to have a tighter geometry...at least at about 3M !!

Trinh...Stop Dick'en around ( HAHAHAHA )..It is now after Sunset in Vietnam....Get those beams out the window !!! I wanna see what the geometry looks like at 50M !!!!!!!!!!!!!!!!!!!!!!! Thanx....CDBeam
 

RedCowboy

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I suspect she doesn't know how to set up ebay for regular mail and express choices, she probably messed that up. I asked her to let me pay express DHL, then her listing changed to show only express mail.

I write she because the emails are signed Sabrina.

Yea, you should let her know because she has a 10 dollar driver and shipping is 45.00
She's not going to sell anything like that.
 

steve001

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Yes I agree and that's information we don't have yet and no issue once in hand, no issue what so ever once in hand.

My dilemma as the price plus shipping is now 150.00 range each diode is which version of FAC corrected diodes will be better at maintaining beam shape over distance, lenses can be adjusted, but how well the FAC has adjusted the divergence of the fast axis is my question.....yes I know we will have to wait and see.

I am interested to know how well these FAC corrected nubm08 diodes compare to a 6X c-lens corrected nubm44 which is a sister diode only wavelength is 455 vs. 445 however raw divergence and output is comparable, and I don't expect they could be any better but they would be more convenient for PBS combining and knife edging, the line output FAC corrected for knife edging and likely the square beam output FAC corrected diodes for PBS combining.........but maybe not, not if one holds it's beam shape better over distance than the other, I am not building a CNC for point blank only use and I fear the square beam FAC corrected diode may not hold it's shape over distance as well as the line output unit might.....again I know we will see in time.

I also have NDB7A75 c-lens corrected beams that are very good and do 5w which I seriously doubt a single lens FAC could match, I would be happily surprised if they are as good or dare I dream better, but given the physics I imagine they are not, however if pretty good then let the beam combining begin.

My issue is how many do I buy now not knowing how long the supply may last and which FAC corrected version will be better at holding it's corrected beam shape, adjusting optics once in hand is not an issue..........I don't expect a guaranteed answer, just looking for insight......your see what ya got when in hand is insight of sorts but I am looking for a bit more cerebral information. :)
Hey steve001 what do you know about FAC FIBER as it's used in the sales description of these FAC corrected diodes ?

Is it saying these FAC lenses are designed for fiber coupling applications such as CNC use ?

I think we are hoping for some magic here and CDBEAM777 called it, they likely did not modify these so we can burn at distance or paint a dot on the moon, but likely for home CNC use......however I do remain hopeful that we can repurpose some of these for " beautiful beaming " applications.

A NUBM07 with a window can and backfill gas would be nice.
Not much. I wonder how long the fiber might be?
 

aaronnoraa

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Very cool!

The sharp is on the right?

How does the divergence and spot size compare to the 1w Nichia?

Hmmmm...I think the FAC corrected Sharp is on the left....because....525nm would have more a yellow tint...and the left unit looks to have a yellow tint....IMNSHO...also...the beam on the left appears to have a tighter geometry...at least at about 3M !!

Trinh...Stop Dick'en around ( HAHAHAHA )..It is now after Sunset in Vietnam....Get those beams out the window !!! I wanna see what the geometry looks like at 50M !!!!!!!!!!!!!!!!!!!!!!! Thanx....CDBeam

My guess is that they're maybe both the Sharp diodes (that aren't FAC corrected, pretty sure the Sharp diodes aren't offered in FAC) with different wavelengths between samples? That or just the one of the right is the Sharp.. either way I'm pretty sure the Sharp isn't a FAC modified diode...
 

logsquared

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My guess is that they're maybe both the Sharp diodes (that aren't FAC corrected, pretty sure the Sharp diodes aren't offered in FAC) with different wavelengths between samples? That or just the one of the right is the Sharp.. either way I'm pretty sure the Sharp isn't a FAC modified diode...
Im pretty sure you are correct that its not FACed

I was hoping to get a comparison of the new sharp (un FACed) green to the nichia. The 700mW sharp red has half the emitter size of the P73. I was hoping for half the emitter size on the new green too. Fingers crossed.
 

aaronnoraa

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Great discussions to all of you !!! This is sure changing fast...prices going up !! $45 for shipping a diode ??? Come on !!!! Well....basically...we are at their discretion...PERIOD !! To Bad...So Sad !! OK...I can see FAC for CNC at the Blue line...Why Red and Green ????

Later,
CDBeam

They seriously need to to do something about that and lower the prices for shipping, charging $45 dollars to ship something that everyone knows costs less than $3 to ship which weighs less than 10 grams is what people expect from scandalous, bottom feeding, dishonest sellers and I know that Laser Tree is better than that.. they're going to lose a lot of sales and potential customers with ridiculous shipping fees like that by giving people the wrong impression of their integrity (before even considering the total price). People have learned how to watch out for scams and grossly inflated shipping prices are one of the things people look out for.

If you need to make more money from the items you're selling, raise the price but leave the shipping cost at the actual cost of shipping. Raising shipping prices to make extra money just.... looks bad. Looks really, really bad.
 
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aaronnoraa

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The line output FAC corrected diode may be better at holding it's beam shape over distance as it's dimensionally reflective of the P/N junction and I don't see the square output FAC corrected diode as having enough physical space to match axis length and correct divergence is such a short distance given the line shape of the P/N junction ect.....but I hope it has done the magic that we desire and I am very curious about the shape of the FAC if it has.

I'm still really confused about the "line" FAC corrected diodes... for three reasons.

1. If the output geometry is a line, whether it's a longer or shorter line than the uncorrected beam.. it's still a line.. is the photo of the spot provided by the seller taken a few inches from the output or many feet? If it's only a few inches it would imply that the fast axis isn't being adjusted in this case, but rather the slow axis is being adjusted.. a "SAC"?

2. Assuming the picture is taken of the spot far field, is the fast axis being made longer, like a line generator (exactly not what we want).. or shorter?

3. If shorter, this would be partial fast axis correction? Fast halfassxis correction? If it's longer than an uncorrected beam, just call it what it is.. a line generator.

So just.. what? Huh? I mean, ? Shrug...
 
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logsquared

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I'm still really confused about the "line" FAC corrected diodes... for three reasons.

1. If the output geometry is a line, whether it's a longer or shorter line than the uncorrected beam.. it's still a line, implying that the fast axis isn't being adjusted in this case, but rather the slow axis is being adjusted.. a "SAC"?

2. Is the slow axis being made longer, like a line generator (exactly not what we want).. or shorter?

3. If shorter, how does that effect the beam in the far field? My guess is, not much since the fast axis should diverge at the same rate as an uncorrected beam, making the spot width unchanged but the spot "thickness" slightly less (remember the fast/slow axis lengths flip just a few feet away from the diode). Maybe this arrangement is useful only for CNC as the beam would be tighter a couple inches away from the diode and have higher energy density?

Actually that would imply that the "slow axis correction" would be correcting by reducing the slow axis rather than expanding.. which just isn't how that works.

So just.. what? Huh? I mean, ? Shrug...
Look at the FA raw divergence on their spec sheets for "linear" and "square" of the same type diode. This should "clue you in" to whats happening.
 

aaronnoraa

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Look at the FA raw divergence on their spec sheets for "linear" and "square" of the same type diode. This should "clue you in" to whats happening.
Yeah, I see that for the 525nm diode, the parallel/perpendicular divergence is 11/11 for the square and 11/1 for the line. It just doesn't make sense that they were able to correct to 1mrad, usually correction is done by expansion and I don't know how expansion could result in both a line AND better divergence. I guess I'll just have to wait until someone posts pictures of the behaviour of the two types of FAC side by side.

I hope this doesn't get too far off topic but since we're talking about Laser Tree..

HOT DAMN!!
It seems that they now have fiber coupled assemblies, prebuilt with diode included, for $75-$175 depending on the diode.. Isn't this taking care of the hard part, the actual fiber coupling itself, allowing us to get perfectly circularized beams via multimode diode fiber coupled, then fiber output collimated?

 
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RedCowboy

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this.JPG

This looks pretty good, the square is actually square.........hope is rising :)

They are not expanding the slow but reducing the divergence of the fast.

If you look at the P/N junction it's a slit and the fast axis diverges faster so at a point away from the facet ( fraction of a mm ) the beam is square in that one spot, so if the plano aspheric FAC lens is positioned just right in 3D then the beam will continue to diverge evenly as the FAC has matched the fast axis to the slow from where it's square, where the fast caught up with the slow as the slow started much wider.

You can see in my last 2 pics how the raw beam diverges much faster on the fast axis so the narrow catches up with the wide which diverges much slower and that's the point where the fast axis divergence would be reduced by the FAC lens in the case of the square output unit.

1kxnubm06a.JPG

nubm06raw4.JPG

nubm06rawtabletop.JPG

nubm06raw2b.JPG
 
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logsquared

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Yeah, I see that for the 525nm diode, the parallel/perpendicular divergence is 11/11 for the square and 11/1 for the line. It just doesn't make sense that they were able to correct to 1mrad, usually correction is done by expansion and I don't know how expansion could result in both a line AND better divergence. I guess I'll just have to wait until someone posts pictures of the behaviour of the two types of FAC side by side.
Its 1 deg not 1mRad. 1 deg = about 17mRad. Think about this. A standard 8mm EFL aspherical lens produces aprox .2mRad on the FA, A 4mm EFL (G2) produces aprox .4mRad, A 2mm EFL produces a aprox .8mRad. So just extrapolate backwards to 17mRad. Very short EFL for collimation. Most FACs i have seen are not set for infinity focus so the actual EFL is probably larger than would seem. Maybe .5mm or so.
 

RedCowboy

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OK I see why people say expanding the slow, it happens after the fast axis has past/exceeded the starting width of the slow, after where it was naturally square for a moment.....Ok, and that would give a lot more working space..........I get it now. :)
 
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Coonie

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Hey guys about the shipping, there's two options to choose from. I gotta catch up on reading this thread. Hope it wasn't said already
 

Alaskan

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Regarding shipping on the Laser Tree offerings, if you click on shipping you can see free shipping is an option too, she needs to reverse which shows so expedited is the buried option, not the first.

 




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