Mitsubishi ML520G71...Red Holy Grail or Flashlight Fail ??

[Solarfire]

Price drop on the 71s to 50$ + free shipping.. http://www.ebay.de/itm/Mitsubishi-63...item3cbee62ca6

[logsquared]

I have been very tied up with travel for work lately....so "Laser Fun Time" has been greatly limited !! Tried some surplus C-Lenses...deadend !! Been working with Kiyoukan...he came up with a concept...see attached drawing !! to knife edge two (2) beams...mid-correction...so each LD has a dedicated plano convex....then knife edge combine where the propagation has the smallest geometry....then a common higher mag. plano convex !! Then the standard WP and PBS for a quad...this is my current path...waiting on glass...as usual !! We will see how this works !!! The quest continues !!

BEAM

I think that set-up will be the hardest thing you have ever tried to line up and adjust! The point where the beam waist (knife mirror) is at is so small the smallest amount of error will wipe out all your power. Also, I believe you will end up with a really large aperture size. Any lateral displacement of the beams before the objective mirror will act as a "lever". Therefore, the output beam width will be twice the size of one beam if the far field spots are overlapped.

Don't let me spoil your fun though. I am curious to see how it all works out experimentally.

[LaNeK779]

hey mr beam, long time no see. hope all is well and constructive

i have seen kiyoukan's design and i have been troubled by the choice of two planoconvex lenses (the keplerian vs gallilean telescope thingy etc etc)
i thought that due to the "extreme" optical characteristics of this diode a positive and negative lens telecope would work better
so, i'm more than anxious to see how this goes

@fenechlaser: what fl cyl lenses did you use if i may? a group buy would be the thing to do, as soon as we "finalise"our specs

[RGB LASER VERKOOP]

i am working on:

2,5W green cni

6x 635nm red: optima lenses with PBS cube, 4X telescope, 2 sets of prisms, ~3.3mm X 3.3mm ~1.4mRad both directions.
4x 445nm diodes o-like, PBS with cube. gives 4-4.8W 4.5mm X 4mm with .2 X 1.8mRad. Add prism to reduce divergence to 1.3-1.4 mRad with 4.5mm X 5mm aperature.

This will be a 9W RGB in a small case for a nice price
hope finished in 2 weeks, i post pics again!

I build it together, projector + green from china CNI, the diode's arays come from a friend in USA.
so this is a made in Holland, USA, China, mix projector
laser greets joost

[kiyoukan]

longsquad
It wont be any where as bad as you think the very large c-lenses i am using. the larger lateral spacing wont make much of a difference if you do it right the spacing will be less than 1mm.
So it may be a tiny bit wider but so far i am the only one in my testing to use very large C-lenses.
And yes i am going to be doing an optics GB.
I mentioned it on lpf and here on pl.
more information on the first of the month when my supplier comes back from spring festival.
Some good news.
The usa supplier has replied to me with a price for 2mm efl lenses with a NA of 0.5 and a diameter of 3mm
In an order of 50 lenses we can get a price of 20$ a lens.
So its cheaper but im still going to try to get that down to 15$ a lens
If we order more than 150 lenses we can get price down further.
i have a few other suppliers i am talking to about getting them made.
So if you guys would be up for a GB let me know.

[logsquared]

longsquad
It wont be any where as bad as you think the very large c-lenses i am using. the larger lateral spacing wont make much of a difference if you do it right the spacing will be less than 1mm.
So it may be a tiny bit wider but so far i am the only one in my testing to use very large C-lenses.

I think I understand? What are the focal lengths of the telescope lenses? Also, what aperture size Vs. divergence does it achieve?

[kiyoukan]

with my current 3.3fl lens i got a beam of just under 4mm at aperture and a divergence around 1.1
I have new lenses from dave and 2 other company's on the way with FL from 2 to 2.25 to 2.5 and my current setup was done with a 3.3FL lens
So i will have enough lenses to do alot of testing.
The c lenses EFL are a 10 and a 60 and the second lens is over 30mm wide
Once all my lenses arrive i will do alot of testing.
I will be happy with a beam of around 3.6 with a divergence of 1.08
That is my goal and i want to do that without a pin hole.
But i will settle for a beam of 4mm with a 1.1 if i must.

[logsquared]

I have some 2mm coming from Dave as well. I'm stoked to get them and try them out.

I honestly don't see how you can get 3.6mm with 1.08 mRad with two diodes side by side like you propose. The best I have done with a single diode and 8x telescope is a about 4.5mm with .9mRad at .5A. When I took the current higher the aperture size increased.

[kiyoukan]

well i am driving my diodes around 500ma
So maybe when i increase the power it will change.
I didnt say i got a 3.6 but that is what i am shooting for.
What 8x did you use standard surplus?
What diode lens are you using?

[logsquared]

I have been getting my telescope lenses from edmunds optics. 100mm and -12.5mm. I also use 50mm and -12.5. I have found the differences pretty much what you would expect..... with the 50mm the divergence basically doubles and the aperture halves. The results are very similar with the 405g, optenxt 4mm (gives ~10% more power), and a thor 3.1mm (shrinks down the FA to like 3.5mm or so). The distance of the first lens from the collimator has a fairly big effect on the final telescope ratio.

Your 3.6mm x 1.08mRad works out to about the same as my results mathematically.... using both of our measure divergences and my measured aperature we can solve for your aperture.... .9mRad/1.08mRad = 8.3333 X 4.5mm = 3.75mm. so, really close to 3.6mm. I think this is the best we can with out breaking know physical laws Its just a matter of manipulating what we have here to make different arrangement's