NUBM0C 465nm 4.1 Watt Laser Diode with square spot FAC (Fast Axis correction) offered for sale from Laser Tree on ebay by seller: 'sabzh21'

[RedCowboy]

Thats unfortunate, I was hoping the correction would at least make it better than the HL63193MG I already have since they both produce 1W of 638nm.

You can get a module with c-lens correction to correct the aggressive fast axis divergence or optics to do it yourself.

Red Sparrow Modules

www.live-lasersystems.net

Cylindrical Lenses

www.live-lasersystems.net

 

[Gryphon]

Very nice, I do like Phillip’s site and those sparrow modules are very tempting. I asked him about the 425nm module just the other week as something to potentially fill the 405-445nm gap but he says it’s far too blue and similar to the 445nm color to be happy middle ground. Might one day just have to bite the bullet on one of those $500 420nm diodes

 

[RedCowboy]

You can correct the MM beans yourself, but Phillips design is nice and tidy, just depends on what you want to do, laser show, hand held, or just add another beam to your collection.

 

[aaronnoraa]

I got the 638nm FAC square diode today and built it up to test out. It does indeed produce a square dot and makes 1W of bright red light

Unfortunately it still produces a horrid line when focused down. I only have the standard plastic and G8 lenses on hand to test with. I wonder if any of the standard 9mm lenses we have floating around will keep it a square dot when focused.

So, when focused, is the line smaller than that of an "un-fac'd" diode? Sort of an important bit of information that wasn't provided, your post gives the impression that there is no advantage to getting a FAC'd diode

Thats unfortunate, I was hoping the correction would at least make it better than the HL63193MG I already have since they both produce 1W of 638nm.

and I'm not sure that is true. :0)

Also I thought that the consensus in a prior thread about the Laser Tree FAC diodes was that the "Line FAC" option was better than the "Square FAC" option, divergence-wise, with these diodes?

 

[Gryphon]

So, when focused, is the line smaller than that of an "un-fac'd" diode? Sort of an important bit of information that wasn't provided, your post gives the impression that there is no advantage to getting a FAC'd diode

I don't have this diode in an un-FAC'd version so I don't have a one to one comparsion. What I do have is a HL63193MG and that diode produces a "line" spot roughly half as wide as this square FAC diode. I have tested it with a 3E, G2, G8 and stock plastic lenses, all of them produce an unbearably wide line. I did some experimenting with a 90mm magnifying lens and that produces a superbly small and tight dot at range but the beam leaving the lens is enormous.

Also I thought that the consensus in a prior thread about the Laser Tree FAC diodes was that the "Line FAC" option was better than the "Square FAC" option, divergence-wise, with these diodes?

That I am not sure about, I went with the square FAC in hopes of achieving something similar to what Drake achieved in this video where he compares the HL63193MG to a square FAC red.

He manages quite good collimation all within the standard 12mm module and the data sheet he shows is identical to the one LaserTree uses (I know that's not much considering there's nothing to stop one Chinese company from ripping off information from another Chinese company)

 

[RedCowboy]

The 5W blue FAC enhanced diode which is comparable to a NDB7A75 diode has a tighter output due to the FAC fiber, so much so that you can use a 3 element lens without the usual 30% or so clipping losses and focused with our typically used lenses ( G2/3E/G8 ) makes a tighter beam for cutting/etching up close, but your far field beam waist/spot will be larger.

Here you see a convex cylindrical lens is used, one for each axis without a primary asphericl lens, this would not be possible without the FAC fiber enhancement because normally the divergence is much too aggressive.

This pic was taken by Smackitup of a 20W made from 4 x FAC enhanced diodes, the 1st and 2nd optic in each row are c-lenses ( one for each axis ) and the 3rd optic in each row is a reflector used to knife edge the beams.

The thread is here.