Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers



Laser Pointer Store

Using factory 12x sleds for beam combining?

Exerd

New member
Joined
Jan 2, 2010
Messages
443
Points
0
I have some of the SF-512 sleds with 12X 405nm and 650nm(?) diodes. It looks like these sleds use knife edging to combine the beams into one output beam.

Is this a true knife edge design for combining beams, or do hobbyists use a more efficient design? I'm just wondering if if is at all possible to use the sled in factory layout, maybe change some of the lenses if possible and glue new ones in, to achieve an increased beam output. Possible? Probable?

I have a lathe and mill...was thinking if there would be anyway to ditch the red diode and maybe glue in and align a custom block with second 405nm 12X in its place, or do anything to make the sled useful in a lab build.

Any chance messing with those sled optics to gain something useful in a lab build box, or is it a complete waste of time to attempt?

Thanks for input.
 

Exerd

New member
Joined
Jan 2, 2010
Messages
443
Points
0
Re: Using factory 12x sleds for 405nm + 445nm knife-edging?

Has anyone studied the drive sleds them selves, like SF-512WB blue ray?? It just looks so intriguing when i look at the sled optics.

I'm going to have to look up 'knife edging' so i know when they are closely setup well and pros/cons of a knife edged setup.

What if you have two SW512 sleds, and get rid of the 605nm (or 650nm) red diodes for more aligned 445nm diodes in their old place. between the two 445nm pairs on each sled, you end up with four total, two 405nms (12xs) and two 445nms, all carefully repressed in new CNC'd heat blocks and knife edged on the way through to the bottom output. Now take the output beam of each knife edged sled (2x 445nm, 2x 405nm), and point those two beams coming out the bottom into a third sled's original diode inputs. Would you end up with 4 total beams knife edged together, or is there trouble with this?

I had assumed some new optics would need to be glued or used for the 445nm characteristics and ridding out the red. But can beams keep recombining like this back into one visible beam? What is the limit, or what would one do if he wanted to combine four A-140 445nm diodes into a single beam? Is there something better than knife edging? THOR Lab's new catalog has 445nm A.R. coated additions across the board for optics lenses, prism pairs, expanders, and etc. They adjusted to 445nm quite quickly. I love it.

I just want to combine the 4 diodes I have, actually the 2 and 2. But I wouldn't mind seeing four 445nms cranking together! :) Even if I made micrometer and spin adjustment at the diodes, for each one, XYZ, so I could dial all the corrected dots to meet at say 2000 yards, that would be cool! That would be a pain in the you-know-what, too.

I would mount these down to copper plate on a larger encased mount, mill where needed, glue where needed, etc, just to use a small water cooling plate and radiator for PC to cool them off. I know that much power would create a lot of local heat, but that is no problem behind the curtains.

I'm grabbing a set of mounted prism pairs for 445nm from TLabs. I gotta see what the price is all about. :p They're too expensive, and that draws me towards them. :) If I get a perfect dot, then expand it, oh boy I would be happy.

Thanks for any ideas concerning this. I'm sure I'm missing something somewhere or it would be done by now elsewhere! Right?
 

Exerd

New member
Joined
Jan 2, 2010
Messages
443
Points
0
Can the sleds be used? Anyone ever tried it? I'm going to soon so I will report back tomorrow.
 

Meatball

New member
Joined
Feb 1, 2008
Messages
2,989
Points
0
I think the KES 40A sleds were used at one time to do this, so If the sled seems to be engineered to combine the beams of 3 separate diodes already, then I don't see why not!
 

Exerd

New member
Joined
Jan 2, 2010
Messages
443
Points
0
I think the KES 40A sleds were used at one time to do this, so If the sled seems to be engineered to combine the beams of 3 separate diodes already, then I don't see why not!

I just have a few of the SF-512w(?) sleds that have the decent 12x 405nm and 650nm diodes.

Obviously these are tuned very precisely from the factory to read the disk, so my theory was that maybe it would be a good idea to utilize the sleds themselves for beam combining, mounting the sleds in steps on a mounting board. Each time diode power is injected, it is done so through the location of a red diode location. A combined beam. The first sled would pump light out from two diodes, every sled after that would have its red removed for the new beam to be injected in with more 405nm light. You could align and stack like 6 sleds, the way it looks. Looks can be deceiving, though.
 

qumefox

New member
Joined
Mar 26, 2010
Messages
3,234
Points
0
The SF-BW512 sleds don't combine the 405 with anything nor is there any knife edging done in the sled. The optical paths for the 405 is entirely separate from the 780/660 side. If you look, the two separate output lenses tell that story. And if you crack it open, you'll see that it has separate optical pickups for each side as well.

These, and most bluray sleds, especially burners, do this because the focal lengths and coatings are too different from what's required for red. There's just no real compromise in optics between the two that doesn't result in too many losses for the system to function properly.
 
Last edited:

BShanahan14rulz

Well-known member
Joined
Dec 29, 2009
Messages
3,175
Points
63
However, you may be able to use that PBS cube in there to combine two beams without removing the cube from the sled.
 

qumefox

New member
Joined
Mar 26, 2010
Messages
3,234
Points
0
The thing is those PBS cubes are tiny.. like 2mmx2mmx2mm. You'd have considerable losses since most collimated diode outputs are larger than that. Plus they're only coated for 405, so you'd have more losses using it with a red. The dichros in the sled would be a better option.
 
Last edited:

qumefox

New member
Joined
Mar 26, 2010
Messages
3,234
Points
0
They are, but crack open a 512L sled and try to make use of that tiny one. heh. I'm not saying it can't be used. Only that I don't think it'd be worth it. You'd get less losses using the dicros in the sled to combine.. Or just buying a larger, broadband AR coated PBS.
 

Exerd

New member
Joined
Jan 2, 2010
Messages
443
Points
0
Guys, I screwed up. I had bought 405 sleds, and 655nm sleds together.

Well one of the boxes had a blue dot, I assumed it was the 405 sled, started studying it, and then when you mentioned here it doesn't knife edge, I take a look and here I am staring at the 655nm sled.

Yeah the SW512 has two output lenses. The 655nm "unknown sled" has one output lens, and I still can't figure out the knife edging deal. It seems like it would be impossible two get two overlaid beams without a cube.

If you have a cube with 45 degree half-silver mirror, since one reflects off front of mirror and one beam passes through @ 50% power, couldn't you take the undesired reflected beams, pass them around on 100% silver mirrors so they don't destructively interfere, and pass once again through the initial cube front mirror side so you get another 50% of the reflected beam?

So like 50%, 75%, 87.5%, 93.75%? No that can't work I suppose. Worth the thought I guess. lol
 




Top